feat: cleanup code

independentTest.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+
+
+REPO="https://gitea.hb.dhbw-stuttgart.de/f.holzwarth/JavaCompilerCore.git"
+TDIR="./testBuild"
+
+rm -rf "$TDIR" 2>/dev/null
+mkdir $TDIR
+
+cd $TDIR
+git clone $REPO .
+git checkout feat/unify-server
+# git checkout 93e1a8787cd94c73f4538f6a348f58613893a584
+# git checkout dad468368b86bdd5a3d3b2754b17617cee0a9107 # 1:55
+# git checkout a0c11b60e8c9d7addcbe0d3a09c9ce2924e9d5c0 # 2:25
+# git checkout 4cddf73e6d6c9116d3e1705c4b27a8e7f18d80c3 # 2:27
+# git checkout 6c2d97b7703d954e4a42eef3ec374bcf313af75c # 2:13
+# git checkout f722a00fbb6e69423d48a890e4a6283471763e64 # 1:35
+# git checkout f0a4a51ce65639ce9a9470ff0fdb538fdf9c02cc # 2:19
+# git checkout 1391206dfe59263cdb22f93371cfd1dd5465d97f # 1:29
+
+date "+%Y.%m.%d %H:%M:%S"
+# sed -i -e 's/source>21/source>23/g' pom.xml
+# sed -i -e 's/target>21/target>23/g' pom.xml
+
+
+mvn clean compile -DskipTests package
+time java -jar target/JavaTXcompiler-0.1-jar-with-dependencies.jar resources/bytecode/javFiles/Matrix.jav;
+
+# mvn clean compile test
+
+
+echo -e "\nCleanup... "
+cd -
+rm -rf "$TDIR" 2>/dev/null
+
+echo -e "\nFinished "
+date "+%Y.%m.%d %H:%M:%S"
+echo -e "\n "
+

pom.xml

@@ -44,6 +44,26 @@ http://maven.apache.org/maven-v4_0_0.xsd">
 			<artifactId>asm</artifactId>
 			<version>9.5</version>
 		</dependency>
+		<dependency>
+			<groupId>org.java-websocket</groupId>
+			<artifactId>Java-WebSocket</artifactId>
+			<version>1.5.2</version>
+		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-simple</artifactId>
+			<version>1.7.25</version>
+		</dependency>
+		<dependency>
+			<groupId>com.fasterxml.jackson.core</groupId>
+			<artifactId>jackson-databind</artifactId>
+			<version>2.17.2</version>
+		</dependency>
+		<dependency>
+			<groupId>com.diogonunes</groupId>
+			<artifactId>JColor</artifactId>
+			<version>5.5.1</version>
+		</dependency>
 	</dependencies>
 
 	<build>
@@ -138,4 +158,4 @@ http://maven.apache.org/maven-v4_0_0.xsd">
 			<url>file:///${project.basedir}/maven-repository/</url>
 		</repository>
 	</distributionManagement>
-</project>
+</project>

src/main/java/de/dhbwstuttgart/bytecode/Codegen.java

@@ -8,6 +8,7 @@ import de.dhbwstuttgart.target.generate.ASTToTargetAST;
 import de.dhbwstuttgart.target.tree.*;
 import de.dhbwstuttgart.target.tree.expression.*;
 import de.dhbwstuttgart.target.tree.type.*;
+import de.dhbwstuttgart.util.Logger;
 import org.objectweb.asm.*;
 
 import java.lang.invoke.*;
@@ -19,6 +20,8 @@ import static de.dhbwstuttgart.target.tree.expression.TargetBinaryOp.*;
 import static de.dhbwstuttgart.target.tree.expression.TargetLiteral.*;
 
 public class Codegen {
+    public static Logger logger = new Logger("codegen");
+
     private final TargetStructure clazz;
     private final ClassWriter cw;
     public final String className;
@@ -1317,7 +1320,7 @@ public class Codegen {
                 types.add(Type.getObjectType(guard.inner().type().getInternalName()));
                 // TODO Same here we need to evaluate constant;
             } else {
-                System.out.println(label);
+                logger.info(label);
                 throw new NotImplementedException();
             }
         }

src/main/java/de/dhbwstuttgart/bytecode/FunNGenerator.java

@@ -120,7 +120,7 @@ public class FunNGenerator {
             superFunNMethodDescriptor.append(")V");
         }
 
-        System.out.println(superFunNMethodSignature);
+        Codegen.logger.info(superFunNMethodSignature);
 
         ClassWriter classWriter = new ClassWriter(0);
         MethodVisitor methodVisitor;

src/main/java/de/dhbwstuttgart/core/ConsoleInterface.java

@@ -1,46 +1,81 @@
 package de.dhbwstuttgart.core;
 
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.util.Logger;
 import java.io.File;
 import java.io.IOException;
-import java.io.OutputStream;
-import java.io.PrintStream;
 import java.util.*;
-public class ConsoleInterface {
-	private static final String directory = System.getProperty("user.dir");
 
-	public static void main(String[] args) throws IOException, ClassNotFoundException {
-		List<File> input = new ArrayList<>();
-		List<File> classpath = new ArrayList<>();
-        String outputPath = null;
-		Iterator<String> it = Arrays.asList(args).iterator();
-        if(args.length == 0){
-            System.out.println("No input files given. Get help with --help");
-            System.exit(1);
-        }else if(args.length == 1 && args[0].equals("--help")){
-            System.out.println("Usage: javatx [OPTION]... [FILE]...\n" +
-                    "\t-cp\tSet Classpath\n" +
-                    "\t-d\tSet destination directory");
-            System.exit(1);
+public class ConsoleInterface {
+
+  /**
+   * Leave the argument configurations here for the rest of the code to read
+   */
+  public static Logger.LogLevel logLevel = Logger.LogLevel.ERROR;
+  public static boolean writeLogFiles = false;
+  public static Optional<String> unifyServerUrl = Optional.empty();
+
+  public static void main(String[] args) throws IOException, ClassNotFoundException {
+    List<File> input = new ArrayList<>();
+    List<File> classpath = new ArrayList<>();
+    String outputPath = null;
+    Iterator<String> it = Arrays.asList(args).iterator();
+    Optional<Integer> serverPort = Optional.empty();
+
+    if (args.length == 0) {
+      System.out.println("No input files given. Get help with --help");
+      System.exit(1);
+    } else if (args.length == 1 && args[0].equals("--help")) {
+      System.out.println("Usage: javatx [OPTION]... [FILE]...\n" +
+        "\t-cp\tSet Classpath\n" +
+        "\t-d\tSet destination directory\n" +
+        "\t[--server-mode <port>]\n" +
+        "\t[--unify-server <url>]\n" +
+        "\t[--write-logs]\n" +
+        "\t[-v|-vv-|-vvv]");
+      System.exit(1);
+    }
+    while (it.hasNext()) {
+      String arg = it.next();
+      if (arg.equals("-d")) {
+        outputPath = it.next();
+      } else if (arg.startsWith("-d")) {
+        outputPath = arg.substring(2);
+      } else if (arg.equals("-cp") || arg.equals("-classpath")) {
+        String[] cps = it.next().split(":");
+        for (String cp : cps) {
+          classpath.add(new File(cp));
         }
-		while(it.hasNext()){
-            String arg = it.next();
-            if(arg.equals("-d")){
-                outputPath = it.next();
-            }else if(arg.startsWith("-d")) {
-                outputPath = arg.substring(2);
-            }else if(arg.equals("-cp") || arg.equals("-classpath")){
-                String[] cps = it.next().split(":");
-                for(String cp : cps){
-                    classpath.add(new File(cp));
-                }
-            }else{
-                input.add(new File(arg));
-            }
-        }
-		JavaTXCompiler compiler = new JavaTXCompiler(input, classpath, outputPath != null ? new File(outputPath) : null);
-		//compiler.typeInference();
-		compiler.generateBytecode();
-	}
+      } else if (arg.equals("--server-mode")) {
+        serverPort = Optional.of(Integer.parseInt(it.next()));
+      } else if (arg.equals("--unify-server")) {
+        unifyServerUrl = Optional.of(it.next());
+      } else if (arg.equals("--write-logs")) {
+        ConsoleInterface.writeLogFiles = true;
+      } else if (arg.startsWith("-v")) {
+        logLevel = switch (arg) {
+          case "-v" -> Logger.LogLevel.WARNING;
+          case "-vv" -> Logger.LogLevel.INFO;
+          case "-vvv" -> Logger.LogLevel.DEBUG;
+          default -> throw new IllegalArgumentException("Argument " + arg + " is not a valid verbosity level");
+        };
+      } else {
+        input.add(new File(arg));
+      }
+    }
+
+    if (serverPort.isPresent()) {
+      if (unifyServerUrl.isPresent()) throw new RuntimeException("Cannot use unifyServer when in server mode!");
+      JavaTXServer server = new JavaTXServer(serverPort.get());
+      server.listen();
+    }
+    else {
+      JavaTXCompiler compiler = new JavaTXCompiler(input, classpath, outputPath != null ? new File(outputPath) : null);
+      //compiler.typeInference();
+      compiler.generateBytecode();
+      SocketClient.closeIfOpen();
+    }
+  }
 
 
 }

src/main/java/de/dhbwstuttgart/core/JavaTXCompiler.java

@@ -12,6 +12,11 @@ import de.dhbwstuttgart.parser.SyntaxTreeGenerator.SyntaxTreeGenerator;
 import de.dhbwstuttgart.parser.antlr.Java17Parser.SourceFileContext;
 import de.dhbwstuttgart.parser.scope.JavaClassName;
 import de.dhbwstuttgart.parser.scope.JavaClassRegistry;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.packet.SetAutoclosePacket;
+import de.dhbwstuttgart.server.packet.UnifyRequestPacket;
+import de.dhbwstuttgart.server.packet.UnifyResultPacket;
 import de.dhbwstuttgart.syntaxtree.ClassOrInterface;
 import de.dhbwstuttgart.syntaxtree.GenericTypeVar;
 import de.dhbwstuttgart.syntaxtree.Method;
@@ -35,10 +40,13 @@ import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
 import de.dhbwstuttgart.typeinference.constraints.Pair;
 import de.dhbwstuttgart.typeinference.result.ResultSet;
 import de.dhbwstuttgart.typeinference.typeAlgo.TYPE;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
 import de.dhbwstuttgart.typeinference.unify.RuleSet;
 import de.dhbwstuttgart.typeinference.unify.TypeUnify;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import de.dhbwstuttgart.typeinference.unify.distributeVariance;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.FiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
 import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
 import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
@@ -49,6 +57,7 @@ import de.dhbwstuttgart.typeinference.unify.UnifyResultListenerImpl;
 import de.dhbwstuttgart.typeinference.unify.UnifyResultModel;
 import de.dhbwstuttgart.typeinference.unify.UnifyTaskModel;
 
+import de.dhbwstuttgart.util.Logger;
 import java.io.*;
 import java.lang.reflect.Modifier;
 import java.nio.file.Path;
@@ -61,14 +70,17 @@ import org.apache.commons.io.output.NullOutputStream;
 
 public class JavaTXCompiler {
 
+	// do not use this in any code, that can be executed serverside!
+	public static PlaceholderRegistry defaultClientPlaceholderRegistry = new PlaceholderRegistry();
+	public static Logger defaultLogger = new Logger();
+
 	// public static JavaTXCompiler INSTANCE;
 	final CompilationEnvironment environment;
 	Boolean resultmodel = true;
-    public final Map<File, SourceFile> sourceFiles = new HashMap<>();
+	public final Map<File, SourceFile> sourceFiles = new HashMap<>();
 
-    Boolean log = false; //gibt an ob ein Log-File nach System.getProperty("user.dir")+""/logFiles/"" geschrieben werden soll?
-    public volatile UnifyTaskModel usedTasks = new UnifyTaskModel();
-    public final DirectoryClassLoader classLoader;
+	public volatile UnifyTaskModel usedTasks = new UnifyTaskModel();
+	public final DirectoryClassLoader classLoader;
 
 	public final List<File> classPath;
 	private final File outputPath;
@@ -76,14 +88,9 @@ public class JavaTXCompiler {
 	public DirectoryClassLoader getClassLoader() {
 		return classLoader;
 	}
-   
-	public JavaTXCompiler(File sourceFile) throws IOException, ClassNotFoundException {
-		this(Arrays.asList(sourceFile), List.of(), new File("."));
-	}
 
-	public JavaTXCompiler(File sourceFile, Boolean log) throws IOException, ClassNotFoundException {
-		this(sourceFile);
-		this.log = log;
+	public JavaTXCompiler(File sourceFile) throws IOException, ClassNotFoundException {
+		this(Collections.singletonList(sourceFile), List.of(), new File("."));
 	}
 
 	public JavaTXCompiler(List<File> sourceFiles) throws IOException, ClassNotFoundException {
@@ -91,6 +98,9 @@ public class JavaTXCompiler {
 	}
 
 	public JavaTXCompiler(List<File> sources, List<File> contextPath, File outputPath) throws IOException, ClassNotFoundException {
+		// ensure new default placeholder registry for tests
+		defaultClientPlaceholderRegistry = new PlaceholderRegistry();
+
 		var path = new ArrayList<>(contextPath);
 		if (contextPath.isEmpty()) {
 			// When no contextPaths are given, the working directory is the sources root
@@ -300,52 +310,51 @@ public class JavaTXCompiler {
 		Set<Set<UnifyPair>> results = new HashSet<>();
 		UnifyResultModel urm = null;
 		// urm.addUnifyResultListener(resultListener);
-		try {
-			logFile = logFile == null ? new FileWriter(new File("log_" + sourceFiles.keySet().iterator().next().getName())) : logFile;
-			IFiniteClosure finiteClosure = UnifyTypeFactory.generateFC(allClasses, logFile, getClassLoader(), this);
-			System.out.println(finiteClosure);
-			urm = new UnifyResultModel(cons, finiteClosure);
-			urm.addUnifyResultListener(resultListener);
-			ConstraintSet<UnifyPair> unifyCons = UnifyTypeFactory.convert(this, cons);
+		logFile = logFile == null ? new FileWriter("log_" + sourceFiles.keySet().iterator().next().getName()) : logFile;
+		Logger logger = new Logger(logFile, "TypeInferenceAsync");
+		UnifyContext context = new UnifyContext(logger, true, urm, usedTasks, defaultClientPlaceholderRegistry);
 
-			Function<UnifyPair, UnifyPair> distributeInnerVars = x -> {
-				UnifyType lhs, rhs;
-				if (((lhs = x.getLhsType()) instanceof PlaceholderType) && ((rhs = x.getRhsType()) instanceof PlaceholderType) && (((PlaceholderType) lhs).isInnerType() || ((PlaceholderType) rhs).isInnerType())) {
-					((PlaceholderType) lhs).setInnerType(true);
-					((PlaceholderType) rhs).setInnerType(true);
-				}
-				return x;
+		IFiniteClosure finiteClosure = UnifyTypeFactory.generateFC(allClasses, logger, getClassLoader(), this, context.placeholderRegistry());
+		logger.info(finiteClosure.toString());
+		urm = new UnifyResultModel(cons, finiteClosure);
+		urm.addUnifyResultListener(resultListener);
+		ConstraintSet<UnifyPair> unifyCons = UnifyTypeFactory.convert(this, cons, context.placeholderRegistry());
 
-			};
-			logFile.write(unifyCons.toString());
-			unifyCons = unifyCons.map(distributeInnerVars);
-			logFile.write(unifyCons.toString());
-			TypeUnify unify = new TypeUnify();
-			// Set<Set<UnifyPair>> results = new HashSet<>(); Nach vorne gezogen
-			logFile.write("FC:\\" + finiteClosure.toString() + "\n");
-			for (SourceFile f : this.sourceFiles.values()) {
-				logFile.write(ASTTypePrinter.print(f));
+		Function<UnifyPair, UnifyPair> distributeInnerVars = x -> {
+			UnifyType lhs, rhs;
+			if (((lhs = x.getLhsType()) instanceof PlaceholderType) && ((rhs = x.getRhsType()) instanceof PlaceholderType) && (((PlaceholderType) lhs).isInnerType() || ((PlaceholderType) rhs).isInnerType())) {
+				((PlaceholderType) lhs).setInnerType(true);
+				((PlaceholderType) rhs).setInnerType(true);
 			}
-			logFile.flush();
-			Set<PlaceholderType> varianceTPHold;
-			Set<PlaceholderType> varianceTPH = new HashSet<>();
-			varianceTPH = varianceInheritanceConstraintSet(unifyCons);
+			return x;
 
-			/*
-			 * PL 2018-11-07 wird in varianceInheritanceConstraintSet erledigt do { //PL 2018-11-05 Huellenbildung Variance auf alle TPHs der Terme auf der jeweiligen //anderen Seite übertragen varianceTPHold = new HashSet<>(varianceTPH); varianceTPH = varianceInheritanceConstraintSet(unifyCons); unifyCons.map( y -> { if ((y.getLhsType() instanceof PlaceholderType) && (y.getRhsType() instanceof PlaceholderType)) { if (((PlaceholderType)y.getLhsType()).getVariance() != 0 &&
-			 * ((PlaceholderType)y.getRhsType()).getVariance() == 0) { ((PlaceholderType)y.getRhsType()).setVariance(((PlaceholderType)y.getLhsType( )).getVariance()); } if (((PlaceholderType)y.getLhsType()).getVariance() == 0 && ((PlaceholderType)y.getRhsType()).getVariance() != 0) { ((PlaceholderType)y.getLhsType()).setVariance(((PlaceholderType)y.getRhsType( )).getVariance()); } } return y; } ); } while (!varianceTPHold.equals(varianceTPH));
-			 */
-
-			// Set<Set<UnifyPair>> result = unify.unifySequential(xConsSet, finiteClosure,
-			// logFile, log);
-			// Set<Set<UnifyPair>> result = unify.unify(xConsSet, finiteClosure);
-			List<Set<Constraint<UnifyPair>>> oderConstraints = unifyCons.getOderConstraints()/*
-																								 * .stream().map(x -> { Set<Set<UnifyPair>> ret = new HashSet<>(); for (Constraint<UnifyPair> y : x) { ret.add(new HashSet<>(y)); } return ret; }).collect(Collectors. toCollection(ArrayList::new))
-																								 */;
-			unify.unifyAsync(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, logFile, log, urm, usedTasks);
-		} catch (IOException e) {
-			System.err.println("kein LogFile");
+		};
+		logger.debug(unifyCons.toString());
+		unifyCons = unifyCons.map(distributeInnerVars);
+		logger.debug(unifyCons.toString());
+		// Set<Set<UnifyPair>> results = new HashSet<>(); Nach vorne gezogen
+		logger.debug("FC:\\" + finiteClosure.toString() + "\n");
+		for (SourceFile f : this.sourceFiles.values()) {
+			logger.debug(ASTTypePrinter.print(f));
 		}
+		// logFile.flush();
+		Set<PlaceholderType> varianceTPHold;
+		Set<PlaceholderType> varianceTPH = new HashSet<>();
+		varianceTPH = varianceInheritanceConstraintSet(unifyCons);
+
+		/*
+		 * PL 2018-11-07 wird in varianceInheritanceConstraintSet erledigt do { //PL 2018-11-05 Huellenbildung Variance auf alle TPHs der Terme auf der jeweiligen //anderen Seite übertragen varianceTPHold = new HashSet<>(varianceTPH); varianceTPH = varianceInheritanceConstraintSet(unifyCons); unifyCons.map( y -> { if ((y.getLhsType() instanceof PlaceholderType) && (y.getRhsType() instanceof PlaceholderType)) { if (((PlaceholderType)y.getLhsType()).getVariance() != 0 &&
+		 * ((PlaceholderType)y.getRhsType()).getVariance() == 0) { ((PlaceholderType)y.getRhsType()).setVariance(((PlaceholderType)y.getLhsType( )).getVariance()); } if (((PlaceholderType)y.getLhsType()).getVariance() == 0 && ((PlaceholderType)y.getRhsType()).getVariance() != 0) { ((PlaceholderType)y.getLhsType()).setVariance(((PlaceholderType)y.getRhsType( )).getVariance()); } } return y; } ); } while (!varianceTPHold.equals(varianceTPH));
+		 */
+
+		// Set<Set<UnifyPair>> result = unify.unifySequential(xConsSet, finiteClosure,
+		// logFile, log);
+		// Set<Set<UnifyPair>> result = unify.unify(xConsSet, finiteClosure);
+		List<Set<Constraint<UnifyPair>>> oderConstraints = unifyCons.getOderConstraints()/*
+																							 * .stream().map(x -> { Set<Set<UnifyPair>> ret = new HashSet<>(); for (Constraint<UnifyPair> y : x) { ret.add(new HashSet<>(y)); } return ret; }).collect(Collectors. toCollection(ArrayList::new))
+																							 */;
+		TypeUnify.unifyAsync(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, context);
+
 		return urm;
 	}
 
@@ -365,96 +374,108 @@ public class JavaTXCompiler {
 
 		final ConstraintSet<Pair> cons = getConstraints(file);
 		Set<Set<UnifyPair>> results = new HashSet<>();
-		try {
-			var logFolder = new File(System.getProperty("user.dir") + "/logFiles/");
-			if (log) logFolder.mkdirs();
-			Writer logFile = log ? new FileWriter(new File(logFolder, "log_" + sourceFiles.keySet().iterator().next().getName())) : new OutputStreamWriter(new NullOutputStream());
-			IFiniteClosure finiteClosure = UnifyTypeFactory.generateFC(allClasses.stream().toList(), logFile, classLoader, this);
-			System.out.println(finiteClosure);
-			ConstraintSet<UnifyPair> unifyCons = UnifyTypeFactory.convert(this, cons);
-			System.out.println("xxx1");
-			Function<UnifyPair, UnifyPair> distributeInnerVars = x -> {
-				UnifyType lhs, rhs;
-				if (((lhs = x.getLhsType()) instanceof PlaceholderType) && ((rhs = x.getRhsType()) instanceof PlaceholderType) && (((PlaceholderType) lhs).isInnerType() || ((PlaceholderType) rhs).isInnerType())) {
-					((PlaceholderType) lhs).setInnerType(true);
-					((PlaceholderType) rhs).setInnerType(true);
-				}
-				return x;
+		PlaceholderRegistry placeholderRegistry = new PlaceholderRegistry();
 
-			};
+		var logFolder = new File(System.getProperty("user.dir") + "/logFiles/");
+		if (ConsoleInterface.writeLogFiles && !logFolder.mkdirs()) throw new RuntimeException("Could not creat directoy for log files: " + logFolder);
+		Writer logFile = ConsoleInterface.writeLogFiles ? new FileWriter(new File(logFolder, "log_" + sourceFiles.keySet().iterator().next().getName())) : new OutputStreamWriter(new NullOutputStream());
+		Logger logger = new Logger(logFile, "TypeInference");
 
-			logFile.write("Unify:" + unifyCons.toString());
-			System.out.println("Unify:" + unifyCons.toString());
-			unifyCons = unifyCons.map(distributeInnerVars);
-			logFile.write("\nUnify_distributeInnerVars: " + unifyCons.toString());
-			TypeUnify unify = new TypeUnify();
-			// Set<Set<UnifyPair>> results = new HashSet<>(); Nach vorne gezogen
-			logFile.write("FC:\\" + finiteClosure.toString() + "\n");
-			logFile.write(ASTTypePrinter.print(sf));
-			System.out.println(ASTTypePrinter.print(sf));
-			logFile.flush();
-			System.out.println("Unify nach Oder-Constraints-Anpassung:" + unifyCons.toString());
-			Set<PlaceholderType> varianceTPHold;
-			Set<PlaceholderType> varianceTPH = new HashSet<>();
-			varianceTPH = varianceInheritanceConstraintSet(unifyCons);
-
-			/*
-			 * PL 2018-11-07 wird in varianceInheritanceConstraintSet erledigt do { //PL 2018-11-05 Huellenbildung Variance auf alle TPHs der Terme auf der jeweiligen //anderen Seite übertragen varianceTPHold = new HashSet<>(varianceTPH); varianceTPH = varianceInheritanceConstraintSet(unifyCons); unifyCons.map( y -> { if ((y.getLhsType() instanceof PlaceholderType) && (y.getRhsType() instanceof PlaceholderType)) { if (((PlaceholderType)y.getLhsType()).getVariance() != 0 &&
-			 * ((PlaceholderType)y.getRhsType()).getVariance() == 0) { ((PlaceholderType)y.getRhsType()).setVariance(((PlaceholderType)y.getLhsType( )).getVariance()); } if (((PlaceholderType)y.getLhsType()).getVariance() == 0 && ((PlaceholderType)y.getRhsType()).getVariance() != 0) { ((PlaceholderType)y.getLhsType()).setVariance(((PlaceholderType)y.getRhsType( )).getVariance()); } } return y; } ); } while (!varianceTPHold.equals(varianceTPH));
-			 */
-
-			// Set<Set<UnifyPair>> result = unify.unifySequential(xConsSet, finiteClosure,
-			// logFile, log);
-			// Set<Set<UnifyPair>> result = unify.unify(xConsSet, finiteClosure);
-			List<Set<Constraint<UnifyPair>>> oderConstraints = unifyCons.getOderConstraints()// .stream().map(x -> {
-			/*
-			 * Set<Set<UnifyPair>> ret = new HashSet<>(); for (Constraint<UnifyPair> y : x) { ret.add(new HashSet<>(y)); } return ret; }).collect(Collectors.toCollection(ArrayList::new))
-			 */;
-			if (resultmodel) {
-				/* UnifyResultModel Anfang */
-				UnifyResultModel urm = new UnifyResultModel(cons, finiteClosure);
-				UnifyResultListenerImpl li = new UnifyResultListenerImpl();
-				urm.addUnifyResultListener(li);
-				unify.unifyParallel(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, logFile, log, urm, usedTasks);
-				System.out.println("RESULT Final: " + li.getResults());
-				System.out.println("Constraints for Generated Generics: " + " ???");
-				logFile.write("RES_FINAL: " + li.getResults().toString() + "\n");
-				logFile.flush();
-				return li.getResults();
+		FiniteClosure finiteClosure = UnifyTypeFactory.generateFC(allClasses.stream().toList(), logger, classLoader, this, placeholderRegistry);
+		logger.info(finiteClosure.toString());
+		ConstraintSet<UnifyPair> unifyCons = UnifyTypeFactory.convert(this, cons, placeholderRegistry);
+		logger.info("xxx1");
+		Function<UnifyPair, UnifyPair> distributeInnerVars = x -> {
+			UnifyType lhs, rhs;
+			if (((lhs = x.getLhsType()) instanceof PlaceholderType) && ((rhs = x.getRhsType()) instanceof PlaceholderType) && (((PlaceholderType) lhs).isInnerType() || ((PlaceholderType) rhs).isInnerType())) {
+				((PlaceholderType) lhs).setInnerType(true);
+				((PlaceholderType) rhs).setInnerType(true);
 			}
-			/* UnifyResultModel End */
-			else {
-				// Set<Set<UnifyPair>> result = unify.unify(unifyCons.getUndConstraints(),
-				// oderConstraints, finiteClosure, logFile, log, new UnifyResultModel(cons,
-				// finiteClosure));
-				Set<Set<UnifyPair>> result = unify.unifyOderConstraints(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, logFile, log, new UnifyResultModel(cons, finiteClosure), usedTasks);
-				System.out.println("RESULT: " + result);
-				logFile.write("RES: " + result.toString() + "\n");
-				logFile.flush();
-				results.addAll(result);
+			return x;
 
-				results = results.stream().map(x -> {
-					Optional<Set<UnifyPair>> res = new RuleSet().subst(x.stream().map(y -> {
-						if (y.getPairOp() == PairOperator.SMALLERDOTWC)
-							y.setPairOp(PairOperator.EQUALSDOT);
-						return y; // alle Paare a <.? b erden durch a =. b ersetzt
-					}).collect(Collectors.toCollection(HashSet::new)));
-					if (res.isPresent()) {// wenn subst ein Erg liefert wurde was veraendert
-						return new TypeUnifyTask().applyTypeUnificationRules(res.get(), finiteClosure);
-					} else
-						return x; // wenn nichts veraendert wurde wird x zurueckgegeben
-				}).collect(Collectors.toCollection(HashSet::new));
-				System.out.println("RESULT Final: " + results);
-				System.out.println("Constraints for Generated Generics: " + " ???");
-				logFile.write("RES_FINAL: " + results.toString() + "\n");
-				logFile.flush();
-				logFile.write("PLACEHOLDERS: " + PlaceholderType.EXISTING_PLACEHOLDERS);
-				logFile.flush();
-			}
-		} catch (IOException e) {
-			System.err.println("kein LogFile");
+		};
+
+		logger.debug("Unify:" + unifyCons.toString());
+		logger.info("Unify:" + unifyCons.toString());
+		unifyCons = unifyCons.map(distributeInnerVars);
+		logger.debug("\nUnify_distributeInnerVars: " + unifyCons.toString());
+		// Set<Set<UnifyPair>> results = new HashSet<>(); Nach vorne gezogen
+		logger.debug("FC:\\" + finiteClosure.toString() + "\n");
+		logger.debug(ASTTypePrinter.print(sf));
+		logger.info(ASTTypePrinter.print(sf));
+		// logFile.flush();
+		logger.info("Unify nach Oder-Constraints-Anpassung:" + unifyCons.toString());
+		Set<PlaceholderType> varianceTPHold;
+		Set<PlaceholderType> varianceTPH = new HashSet<>();
+		varianceTPH = varianceInheritanceConstraintSet(unifyCons);
+
+		/*
+		 * PL 2018-11-07 wird in varianceInheritanceConstraintSet erledigt do { //PL 2018-11-05 Huellenbildung Variance auf alle TPHs der Terme auf der jeweiligen //anderen Seite übertragen varianceTPHold = new HashSet<>(varianceTPH); varianceTPH = varianceInheritanceConstraintSet(unifyCons); unifyCons.map( y -> { if ((y.getLhsType() instanceof PlaceholderType) && (y.getRhsType() instanceof PlaceholderType)) { if (((PlaceholderType)y.getLhsType()).getVariance() != 0 &&
+		 * ((PlaceholderType)y.getRhsType()).getVariance() == 0) { ((PlaceholderType)y.getRhsType()).setVariance(((PlaceholderType)y.getLhsType( )).getVariance()); } if (((PlaceholderType)y.getLhsType()).getVariance() == 0 && ((PlaceholderType)y.getRhsType()).getVariance() != 0) { ((PlaceholderType)y.getLhsType()).setVariance(((PlaceholderType)y.getRhsType( )).getVariance()); } } return y; } ); } while (!varianceTPHold.equals(varianceTPH));
+		 */
+
+		// Set<Set<UnifyPair>> result = unify.unifySequential(xConsSet, finiteClosure,
+		// logFile, log);
+		// Set<Set<UnifyPair>> result = unify.unify(xConsSet, finiteClosure);
+		List<Set<Constraint<UnifyPair>>> oderConstraints = unifyCons.getOderConstraints()// .stream().map(x -> {
+		/*
+		 * Set<Set<UnifyPair>> ret = new HashSet<>(); for (Constraint<UnifyPair> y : x) { ret.add(new HashSet<>(y)); } return ret; }).collect(Collectors.toCollection(ArrayList::new))
+		 */;
+
+		if (ConsoleInterface.unifyServerUrl.isPresent()) {
+			UnifyResultModel urm = new UnifyResultModel(cons, finiteClosure);
+			UnifyContext context = new UnifyContext(logger, true, urm, usedTasks, placeholderRegistry);
+			SocketFuture<UnifyResultPacket> future = SocketClient.execute(
+				UnifyRequestPacket.create(finiteClosure, cons, unifyCons, context.placeholderRegistry())
+			);
+			SocketClient.execute(SetAutoclosePacket.create());
+			return future.get().getResultSet(context);
 		}
-		return results.stream().map((unifyPairs -> new ResultSet(UnifyTypeFactory.convert(unifyPairs, Pair.generateTPHMap(cons))))).collect(Collectors.toList());
+		else if (resultmodel) {
+			/* UnifyResultModel Anfang */
+			UnifyResultModel urm = new UnifyResultModel(cons, finiteClosure);
+			UnifyResultListenerImpl li = new UnifyResultListenerImpl();
+			urm.addUnifyResultListener(li);
+			UnifyContext context = new UnifyContext(logger, true, urm, usedTasks, placeholderRegistry);
+			TypeUnify.unifyParallel(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, context);
+			logger.info("RESULT Final: " + li.getResults());
+			logger.info("Constraints for Generated Generics: " + " ???");
+			logFile.write("RES_FINAL: " + li.getResults().toString() + "\n");
+			// logFile.flush();
+			return li.getResults();
+		}
+		/* UnifyResultModel End */
+		else {
+			// Set<Set<UnifyPair>> result = unify.unify(unifyCons.getUndConstraints(),
+			// oderConstraints, finiteClosure, logFile, log, new UnifyResultModel(cons,
+			// finiteClosure));
+			UnifyContext context = new UnifyContext(logger, false, new UnifyResultModel(cons, finiteClosure), usedTasks, placeholderRegistry);
+			Set<Set<UnifyPair>> result = TypeUnify.unifyOderConstraints(unifyCons.getUndConstraints(), oderConstraints, finiteClosure, context);
+			logger.info("RESULT: " + result);
+			logFile.write("RES: " + result.toString() + "\n");
+			// logFile.flush();
+			results.addAll(result);
+
+			results = results.stream().map(x -> {
+				Optional<Set<UnifyPair>> res = new RuleSet(placeholderRegistry).subst(x.stream().map(y -> {
+					if (y.getPairOp() == PairOperator.SMALLERDOTWC)
+						y.setPairOp(PairOperator.EQUALSDOT);
+					return y; // alle Paare a <.? b erden durch a =. b ersetzt
+				}).collect(Collectors.toCollection(HashSet::new)));
+				if (res.isPresent()) {// wenn subst ein Erg liefert wurde was veraendert
+					return new TypeUnifyTask(context).applyTypeUnificationRules(res.get(), finiteClosure);
+				} else
+					return x; // wenn nichts veraendert wurde wird x zurueckgegeben
+			}).collect(Collectors.toCollection(HashSet::new));
+			logger.info("RESULT Final: " + results);
+			logger.info("Constraints for Generated Generics: " + " ???");
+			logger.debug("RES_FINAL: " + results.toString() + "\n");
+			// logFile.flush();
+			logger.debug("PLACEHOLDERS: " + placeholderRegistry);
+			// logFile.flush();
+		}
+
+		return results.stream().map((unifyPairs -> new ResultSet(UnifyTypeFactory.convert(unifyPairs, Pair.generateTPHMap(cons), placeholderRegistry)))).collect(Collectors.toList());
 	}
 
 	/**
@@ -586,10 +607,6 @@ public class JavaTXCompiler {
 		}
 	}
 
-	/**
-	 * @param path - output-Directory can be null, then class file output is in the same directory as the parsed source files
-	 * @return
-	 */
 	public Map<JavaClassName, byte[]> generateBytecode(File sourceFile) throws ClassNotFoundException, IOException {
 		var sf = sourceFiles.get(sourceFile);
 		if (sf.isGenerated()) return null;
@@ -644,15 +661,15 @@ public class JavaTXCompiler {
 		FileOutputStream output;
 		for (JavaClassName name : classFiles.keySet()) {
 			byte[] bytecode = classFiles.get(name);
-			System.out.println("generating " + name + ".class file ...");
+			defaultLogger.info("generating " + name + ".class file ...");
 			var subPath = preserveHierarchy ? path : Path.of(path.toString(), name.getPackageName().split("\\.")).toFile();
 			File outputFile = new File(subPath, name.getClassName() + ".class");
 			outputFile.getAbsoluteFile().getParentFile().mkdirs();
-			System.out.println(outputFile);
+			defaultLogger.info(outputFile.toString());
 			output = new FileOutputStream(outputFile);
 			output.write(bytecode);
 			output.close();
-			System.out.println(name + ".class file generated");
+			defaultLogger.success(name + ".class file generated");
 		}
 	}
 

src/main/java/de/dhbwstuttgart/core/JavaTXServer.java

@@ -0,0 +1,31 @@
+package de.dhbwstuttgart.core;
+
+import de.dhbwstuttgart.server.SocketServer;
+
+public class JavaTXServer {
+
+  public static boolean isRunning = false;
+
+  final SocketServer socketServer;
+
+  public JavaTXServer(int port) {
+    this.socketServer = new SocketServer(port);
+  }
+
+  public void listen() {
+    isRunning = true;
+    socketServer.start();
+  }
+
+  public void forceStop() {
+    try {
+      socketServer.stop();
+    }
+    catch (InterruptedException exception) {
+      System.err.println("Interrupted socketServer: " + exception);
+    }
+    isRunning = false;
+  }
+
+
+}

src/main/java/de/dhbwstuttgart/exceptions/UnifyCancelException.java

@@ -0,0 +1,11 @@
+package de.dhbwstuttgart.exceptions;
+
+
+/**
+ * Eine Runtime Exception, die für den Fall genutzt wird, dass eine Unifikation abgebrochen wird.
+ * Durch das Werfen einer Exception können Abbrüche auch aus Methodenaufrufen heraus
+ * geprüft werden, da zuvor nur ein return X; stattfinden würde.
+ */
+public class UnifyCancelException extends RuntimeException {
+
+}

src/main/java/de/dhbwstuttgart/parser/JavaTXParser.java

@@ -7,6 +7,7 @@ import de.dhbwstuttgart.parser.antlr.Java17Parser;
 import de.dhbwstuttgart.parser.scope.JavaClassRegistry;
 import de.dhbwstuttgart.syntaxtree.SourceFile;
 
+import de.dhbwstuttgart.util.Logger;
 import org.antlr.v4.runtime.CharStream;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.CommonTokenStream;
@@ -17,6 +18,9 @@ import java.util.ArrayList;
 import java.util.List;
 
 public class JavaTXParser {
+
+    public static Logger logger = new Logger("Parser");
+
     public static Java17Parser.SourceFileContext parse(File source) throws IOException, java.lang.ClassNotFoundException {
         InputStream stream = new FileInputStream(source);
         // DEPRECATED: ANTLRInputStream input = new ANTLRInputStream(stream);

src/main/java/de/dhbwstuttgart/parser/SourceLoc.java

@@ -1,4 +1,25 @@
 package de.dhbwstuttgart.parser;
 
-public record SourceLoc(String file, int line) {
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+
+public record SourceLoc(String file, int line) implements ISerializableData {
+
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    var serialized = new SerialMap();
+    serialized.put("file", file);
+    serialized.put("line", line);
+    return serialized;
+  }
+
+  public static SourceLoc fromSerial(SerialMap data) {
+    return new SourceLoc(
+      data.getValue("file").getOf(String.class),
+      data.getValue("line").getOf(Integer.class)
+    );
+  }
+
 }

src/main/java/de/dhbwstuttgart/parser/SyntaxTreeGenerator/FCGenerator.java

@@ -12,6 +12,7 @@ import de.dhbwstuttgart.syntaxtree.factory.ASTFactory;
 import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
 import de.dhbwstuttgart.syntaxtree.type.*;
 import de.dhbwstuttgart.typeinference.constraints.Pair;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
 import de.dhbwstuttgart.typeinference.unify.model.*;
 
 import java.util.*;
@@ -26,16 +27,21 @@ public class FCGenerator {
      *
      * @param availableClasses - Alle geparsten Klassen
      */
-    public static Set<UnifyPair> toUnifyFC(JavaTXCompiler compiler, Collection<ClassOrInterface> availableClasses, ClassLoader classLoader) throws ClassNotFoundException {
-        return toFC(availableClasses, classLoader).stream().map(t -> UnifyTypeFactory.convert(compiler, t)).collect(Collectors.toSet());
+    public static Set<UnifyPair> toUnifyFC(JavaTXCompiler compiler, Collection<ClassOrInterface> availableClasses, ClassLoader classLoader, PlaceholderRegistry placeholderRegistry) throws ClassNotFoundException {
+        return toFC(
+          availableClasses,
+          classLoader,
+          placeholderRegistry
+        ).stream().map(t -> UnifyTypeFactory.convert(compiler, t, placeholderRegistry))
+          .collect(Collectors.toSet());
     }
 
-    public static Set<Pair> toFC(Collection<ClassOrInterface> availableClasses, ClassLoader classLoader) throws ClassNotFoundException {
+    public static Set<Pair> toFC(Collection<ClassOrInterface> availableClasses, ClassLoader classLoader, PlaceholderRegistry placeholderRegistry) throws ClassNotFoundException {
         HashSet<Pair> pairs = new HashSet<>();
         //PL 2018-09-18: gtvs vor die for-Schleife gezogen, damit immer die gleichen Typeplaceholder eingesetzt werden.
         HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> gtvs = new HashMap<>();
         for(ClassOrInterface cly : availableClasses){
-        	List<Pair> newPairs = getSuperTypes(cly, availableClasses, gtvs, classLoader);
+        	List<Pair> newPairs = getSuperTypes(cly, availableClasses, gtvs, classLoader, placeholderRegistry);
             pairs.addAll(newPairs);
             
             //For all Functional Interfaces FI: FunN$$<... args auf dem Functional Interface ...> <. FI is added to FC 
@@ -75,8 +81,13 @@ public class FCGenerator {
      * @param forType
      * @return
      */
-    private static List<Pair> getSuperTypes(ClassOrInterface forType, Collection<ClassOrInterface> availableClasses, ClassLoader classLoader) throws ClassNotFoundException {
-        return getSuperTypes(forType, availableClasses, new HashMap<>(), classLoader);
+    private static List<Pair> getSuperTypes(
+      ClassOrInterface forType,
+      Collection<ClassOrInterface> availableClasses,
+      ClassLoader classLoader,
+      PlaceholderRegistry placeholderRegistry
+    ) throws ClassNotFoundException {
+        return getSuperTypes(forType, availableClasses, new HashMap<>(), classLoader, placeholderRegistry);
     }
 
     /**
@@ -87,8 +98,13 @@ public class FCGenerator {
      * @return
      * @throws ClassNotFoundException
      */
-    private static List<Pair> getSuperTypes(ClassOrInterface forType, Collection<ClassOrInterface> availableClasses,
-                                            HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> gtvs, ClassLoader classLoader) throws ClassNotFoundException {
+    private static List<Pair> getSuperTypes(
+      ClassOrInterface forType,
+      Collection<ClassOrInterface> availableClasses,
+      HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> gtvs,
+      ClassLoader classLoader,
+      PlaceholderRegistry placeholderRegistry
+    ) throws ClassNotFoundException {
         List<RefTypeOrTPHOrWildcardOrGeneric> params = new ArrayList<>();
         //Die GTVs, die in forType hinzukommen:
         HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> newGTVs = new HashMap<>();
@@ -147,7 +163,7 @@ public class FCGenerator {
             if(superClass.getClassName().equals(ASTFactory.createObjectClass().getClassName())){
                 superTypes = Arrays.asList(new Pair(ASTFactory.createObjectType(), ASTFactory.createObjectType(), PairOperator.SMALLER));
             }else{
-                superTypes = getSuperTypes(superClass, availableClasses, newGTVs, classLoader);
+                superTypes = getSuperTypes(superClass, availableClasses, newGTVs, classLoader, placeholderRegistry);
             }
 
             retList.add(ret);

src/main/java/de/dhbwstuttgart/parser/SyntaxTreeGenerator/StatementGenerator.java

@@ -1,5 +1,6 @@
 package de.dhbwstuttgart.parser.SyntaxTreeGenerator;
 
+import de.dhbwstuttgart.parser.JavaTXParser;
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -259,7 +260,7 @@ public class StatementGenerator {
             ret.setStatement();
             return ret;
         default:
-            System.out.println(stmt.getClass());
+            JavaTXParser.logger.info(stmt.getClass());
             throw new NotImplementedException();
         }
     }

src/main/java/de/dhbwstuttgart/parser/SyntaxTreeGenerator/TypeGenerator.java

@@ -74,7 +74,7 @@ public class TypeGenerator {
                 throw new NotImplementedException();
             }
         } else if (!typeContext.LBRACK().isEmpty()) { // ArrayType über eckige Klammer prüfen
-            // System.out.println(unannTypeContext.getText());
+            // JavaTXParser.logger.info(unannTypeContext.getText());
             throw new NotImplementedException();
         }
         /*

src/main/java/de/dhbwstuttgart/server/ServerTaskLogger.java

@@ -0,0 +1,41 @@
+package de.dhbwstuttgart.server;
+
+import de.dhbwstuttgart.util.Logger;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import org.java_websocket.WebSocket;
+
+public class ServerTaskLogger extends Logger {
+
+  private final WebSocket webSocket;
+  private final SocketServer socketServer;
+  private final LogLevel customLogLevel;
+
+  public ServerTaskLogger(WebSocket webSocket, SocketServer socketServer, LogLevel customLogLevel) {
+    this.webSocket = webSocket;
+    this.socketServer = socketServer;
+    this.customLogLevel = customLogLevel;
+  }
+
+  @Override
+  public boolean isLogLevelActive(LogLevel logLevel) {
+    return logLevel.isHigherOrEqualTo(customLogLevel);
+  }
+
+  @Override
+  protected void print(String s, LogLevel logLevel) {
+    String coloredPrefix = this.getPrefix(logLevel);
+    if (logLevel.isHigherOrEqualTo(LogLevel.ERROR)) {
+      socketServer.sendError(webSocket, coloredPrefix + s, false);
+    }
+    else {
+      socketServer.sendMessage(webSocket, coloredPrefix + s);
+    }
+  }
+
+  @Override
+  protected void write(String s) {
+    // under no circumstances write anything to a file
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/SocketClient.java

@@ -0,0 +1,202 @@
+package de.dhbwstuttgart.server;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import de.dhbwstuttgart.core.ConsoleInterface;
+import de.dhbwstuttgart.server.packet.IClientToServerPacket;
+import de.dhbwstuttgart.server.packet.IPacket;
+import de.dhbwstuttgart.server.packet.IServerToClientPacket;
+import de.dhbwstuttgart.server.packet.PacketContainer;
+import de.dhbwstuttgart.server.packet.UnifyRequestPacket;
+import de.dhbwstuttgart.server.packet.UnifyResultPacket;
+import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
+import de.dhbwstuttgart.typeinference.constraints.Pair;
+import de.dhbwstuttgart.typeinference.result.ResultSet;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.model.FiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Logger;
+import java.net.URI;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import org.java_websocket.client.WebSocketClient;
+import org.java_websocket.enums.ReadyState;
+import org.java_websocket.handshake.ServerHandshake;
+
+
+/**
+ * The Client-side of the websocket
+ */
+public class SocketClient extends WebSocketClient {
+
+  public static Logger logger = new Logger("SocketClient");
+
+  /**
+   * The singleton object
+   */
+  private static SocketClient socketClient = null;
+
+  /**
+   * List of futures that are still waiting to be fulfilled
+   */
+  private final Map<String, SocketFuture<?>> responseFutures = new HashMap<>();
+
+  private SocketClient(String url) {
+    super(
+      URI.create(url), // target url
+      //SocketServer.perMessageDeflateDraft, // enable compression
+      Map.of( // headers
+        "packetProtocolVersion", SocketServer.packetProtocolVersion
+      )
+    );
+
+    // make sure the url is in a valid format
+    final String regex = "^wss?://(\\w+(\\.\\w+)?)*:(\\d+)$";
+    final Matcher matcher = Pattern.compile(regex).matcher(url);
+    if (!matcher.find()) {
+      throw new RuntimeException("Provided string \"" + url + "\" is not a valid server URL! Use pattern ws(s?)://<host.name>:<port>");
+    }
+
+    try {
+      // wait for the connection to be set up
+      this.connectBlocking();
+      // make sure the connection has been established successfully
+      if (this.getReadyState() != ReadyState.OPEN) {
+        throw new RuntimeException("WebSocket Client could not connect to remote host at " + this.uri);
+      }
+    } catch (InterruptedException exception) {
+      throw new RuntimeException(exception);
+    }
+
+    // add a shutdown hook to close the connection when the process ends or is stopped by a SIGINT signal
+    Runtime.getRuntime().addShutdownHook(new Thread(this::close));
+  }
+
+  private SocketClient(String host, int port, boolean secure) throws InterruptedException {
+    this(String.format("%s://%s:%d/", secure ? "wss" : "ws", host, port));
+  }
+
+  /**
+   * Singleton access method, creates one if none is available
+   *
+   * @return The one and only socketClient
+   */
+  private static SocketClient initializeClient() {
+    if (socketClient == null) {
+      socketClient = new SocketClient(ConsoleInterface.unifyServerUrl.get());
+    }
+    return socketClient;
+  }
+
+  /**
+   * Send a packet to the server (connection will be created, if none is found) and return a future
+   * for the response packet
+   */
+  synchronized public static <T extends IServerToClientPacket> SocketFuture<T> execute(IClientToServerPacket<T> packet) {
+    SocketClient client = initializeClient();
+
+    /*
+     * Create a future that will be associated with the packet and eventually completed
+     */
+    SocketFuture<T> future = packet.getFuture();
+    if (!future.isDone()) {
+      client.responseFutures.put(future.futureId, future);
+    }
+
+    /*
+     * Establish connection, if not already done.
+     * Serialize the packet and send it to the server.
+     * Return the future to be handled by the caller.
+     */
+    try {
+      String json = PacketContainer.serialize(packet);
+      client.send(json);
+    } catch (Exception exception) {
+      logger.exception(exception);
+      throw new RuntimeException("Exception occurred in server connection: ", exception);
+    }
+
+    return future;
+  }
+
+  /**
+   * Shortcut for waiting and retrieving the response immediately
+   *
+   * @param packet The packet to send
+   * @param <T>    The type of response packet to await
+   * @return The response packet, once it is received
+   */
+  public static <T extends IServerToClientPacket> T executeAndGet(IClientToServerPacket<T> packet) {
+    return SocketClient.execute(packet).get();
+  }
+
+  /**
+   * Specific client-side implementations to handle incoming packets
+   */
+  protected void handleReceivedPacket(IPacket packet) {
+    if (!(packet instanceof IServerToClientPacket serverToClientPacket)) {
+      System.err.println("Received package of invalid type + " + packet.getClass().getName());
+      this.close();
+      return;
+    }
+
+    serverToClientPacket.onHandle(this.getConnection(), this);
+  }
+
+  /**
+   * Complete a registered future, so it can be handled by whoever executed the creator task
+   *
+   * @param id      The associated id for this future
+   * @param trigger The object triggering the completion
+   */
+  public void completeResponseFuture(String id, IServerToClientPacket trigger) {
+    SocketFuture<?> future = this.responseFutures.remove(id);
+    if (future == null) return;
+    if (!future.accept(trigger)) {
+      throw new RuntimeException("Packet " + trigger.getClass().getName() + " tried to complete future, but was not allowed to");
+    }
+  }
+
+  public static void closeIfOpen() {
+    if (socketClient != null && socketClient.isOpen()) {
+      socketClient.close();
+    }
+  }
+
+  @Override
+  public void onOpen(ServerHandshake handshakedata) {
+    logger.success("Connected to server with status " + handshakedata.getHttpStatus());
+  }
+
+  @Override
+  public void onMessage(String message) {
+    // logger.info("received: " + message);
+    IPacket packet = PacketContainer.deserialize(message);
+    this.handleReceivedPacket(packet);
+  }
+
+  @Override
+  public void onClose(int code, String reason, boolean remote) {
+    logger.info(
+      "Disconnected from server " +
+        "with code " + code + " " +
+        (reason.isEmpty() ? "" : "and reason " + reason + " ") +
+        "(closed by remote: " + remote + ")"
+    );
+
+    if (!this.responseFutures.isEmpty()) {
+      throw new RuntimeException("Server closed before all required tasks were answered");
+    }
+  }
+
+  @Override
+  public void onError(Exception e) {
+    logger.exception(e);
+    throw new RuntimeException(e);
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/SocketFuture.java

@@ -0,0 +1,48 @@
+package de.dhbwstuttgart.server;
+
+import de.dhbwstuttgart.server.packet.IServerToClientPacket;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+
+public class SocketFuture<T extends IServerToClientPacket> extends CompletableFuture<T> {
+
+  public final String futureId = UUID.randomUUID().toString();
+
+  public final List<Class<T>> allowedTriggers;
+
+  public SocketFuture(List<Class<T>> allowedTriggers) {
+    this.allowedTriggers = allowedTriggers;
+  }
+
+  public boolean accept(IServerToClientPacket trigger) {
+    if (this.allowedTriggers.contains(trigger.getClass())) {
+      this.complete((T)trigger);
+      return true;
+    }
+    return false;
+  }
+
+  @Override
+  public T get() {
+    try {
+      return super.get();
+    }
+    catch (InterruptedException | ExecutionException exception) {
+      throw new RuntimeException(exception);
+    }
+  }
+
+  /**
+   * Special case where the future is immediately fulfilled without a response package similar to
+   * <code>CompletableFuture.completedFuture()</code> but without a value
+   */
+  public static <R extends IServerToClientPacket> SocketFuture<R> completedFuture() {
+    SocketFuture<R> dummyFuture = new SocketFuture<>(new ArrayList<>(0));
+    dummyFuture.complete(null);
+    return dummyFuture;
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/SocketServer.java

@@ -0,0 +1,235 @@
+package de.dhbwstuttgart.server;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import de.dhbwstuttgart.server.packet.ErrorPacket;
+import de.dhbwstuttgart.server.packet.IClientToServerPacket;
+import de.dhbwstuttgart.server.packet.IPacket;
+import de.dhbwstuttgart.server.packet.MessagePacket;
+import de.dhbwstuttgart.server.packet.PacketContainer;
+import de.dhbwstuttgart.util.Logger;
+import java.net.InetSocketAddress;
+import java.util.Collections;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.SynchronousQueue;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+import org.java_websocket.WebSocket;
+import org.java_websocket.drafts.Draft;
+import org.java_websocket.drafts.Draft_6455;
+import org.java_websocket.extensions.permessage_deflate.PerMessageDeflateExtension;
+import org.java_websocket.handshake.ClientHandshake;
+import org.java_websocket.server.WebSocketServer;
+
+public class SocketServer extends WebSocketServer {
+
+  public static Logger logger = new Logger("SocketServer");
+  public static final int maxTasksPerSession = 100;
+  private static boolean serverRunning = false;
+
+  /**
+   * Increase this every time a breaking change to the server communication is done.
+   * This will prevent errors when the server version and client version do not match.
+   */
+  public static final String packetProtocolVersion = "1";
+
+  // create an executor for tasks that will always keep at least one task around
+  private final ThreadPoolExecutor taskExecutor = new ThreadPoolExecutor(1, Integer.MAX_VALUE,60L, TimeUnit.SECONDS, new SynchronousQueue<>());
+  // create an executor for scheduling timeouts
+  private final ScheduledExecutorService timeoutExecutor = Executors.newSingleThreadScheduledExecutor();
+
+  public SocketServer(int port) {
+    super(new InetSocketAddress(port));
+    this.setConnectionLostTimeout(30);
+
+    serverRunning = true;
+    // add a shutdown hook to close all connections when the process ends or is stopped by a SIGINT signal
+    Runtime.getRuntime().addShutdownHook(new Thread(this::onShutdown));
+  }
+
+  public static boolean isServerRunning() {
+    return serverRunning;
+  }
+
+  private void onShutdown() {
+    serverRunning = false;
+    try {
+      for (var webSocket : this.getConnections()) {
+        this.sendError(webSocket, "Sorry, i am shutting down. You are now on your own, good Luck!", true);
+        webSocket.close();
+      }
+      this.stop();
+      taskExecutor.shutdown();
+      timeoutExecutor.shutdown();
+    } catch (InterruptedException exception) {
+      // we are shutting down anyway
+    }
+  }
+
+  @Override
+  public void onOpen(WebSocket webSocket, ClientHandshake clientHandshake) {
+    String ppv = clientHandshake.getFieldValue("packetProtocolVersion");
+    if (!ppv.equals(packetProtocolVersion)) {
+      this.sendError(webSocket,
+        "Mismatch in packet protocol version! Client (you): \"" + ppv + "\" and Server (me): \"" + packetProtocolVersion + "\"",
+        true
+      );
+      webSocket.close(1);
+      return;
+    }
+
+    SocketData socketData = new SocketData(webSocket);
+    logger.info("New connection: " + socketData.id + " (with ppv " + ppv + ")");
+
+    try {
+      sendMessage(webSocket, "Welcome to the server!");
+
+      // wait 10 seconds for the client to send a task and close the connection if nothing has been received until then
+      final int secondsUntilTimeout = 10;
+      timeoutExecutor.schedule(() -> {
+          if (webSocket.<SocketData>getAttachment().totalTasks.get() > 0 || !webSocket.isOpen()) {
+            return;
+          }
+          sendMessage(webSocket, "No task received after " + secondsUntilTimeout + " seconds. Closing connection...");
+          webSocket.close();
+        },
+        secondsUntilTimeout,
+        TimeUnit.SECONDS
+      );
+
+      // and finally, when your program wants to exit
+    } catch (Exception e) {
+      logger.exception(e);
+      webSocket.close(1, e.getMessage());
+    }
+  }
+
+  @Override
+  public void onClose(WebSocket webSocket, int code, String reason, boolean remote) {
+    SocketData socketData = webSocket.getAttachment();
+    logger.info("Connection closed: " + socketData.id);
+    logger.info(
+      "Disconnected client " + socketData.id + " " +
+        "with code " + code + " " +
+        (reason.isEmpty() ? "" : "and reason " + reason + " ") +
+        "(closed by client: " + remote + ")"
+    );
+
+  }
+
+  @Override
+  public void onMessage(WebSocket webSocket, String s) {
+    // logger.info("Received: " + s.substring(0, 50));
+    IPacket reconstructedPacket = PacketContainer.deserialize(s);
+    try {
+      this.onPacketReceived(webSocket, reconstructedPacket);
+    } catch (JsonProcessingException e) {
+      logger.exception(e);
+      this.log(webSocket, "Error on processing incoming package: " + e.getMessage());
+    }
+  }
+
+  @Override
+  public void onError(WebSocket webSocket, Exception e) {
+    if (webSocket != null) {
+      log(webSocket, e.getMessage());
+      webSocket.close();
+    }
+    logger.exception(e);
+  }
+
+  @Override
+  public void onStart() {
+    logger.success("Websocket server started on port " + this.getPort());
+  }
+
+  /**
+   * A shorthand method for sending informational messages to the client
+   */
+  public void sendMessage(WebSocket webSocket, String text) {
+    try {
+      MessagePacket message = MessagePacket.create(text);
+      webSocket.send(PacketContainer.serialize(message));
+    } catch (Exception e) {
+      System.err.println("Failed to send message: " + text);
+      logger.exception(e);
+    }
+  }
+
+  /**
+   * A shorthand method for sending error messages to the client
+   */
+  public void sendError(WebSocket webSocket, String text, boolean isFatal) {
+    try {
+      ErrorPacket error = ErrorPacket.create(text, isFatal);
+      webSocket.send(PacketContainer.serialize(error));
+    } catch (Exception e) {
+      logger.exception(e);
+      log(webSocket, "Failed to send error: " + text);
+    }
+  }
+
+  /**
+   * The server-side implementation on how to handle certain packets when received
+   */
+  private void onPacketReceived(WebSocket webSocket, IPacket packet) throws JsonProcessingException {
+    SocketData socketData = webSocket.getAttachment();
+
+    // limit the number of tasks per connection
+    if (socketData.totalTasks.get() >= maxTasksPerSession) {
+      sendError(webSocket, "Exceeded the maximum amount of " + maxTasksPerSession + " tasks per session", true);
+      webSocket.close();
+      return;
+    }
+
+    // only allow packets that are meant to be handled by the server
+    if (!(packet instanceof IClientToServerPacket<?> clientToServerPacket)) {
+      sendMessage(webSocket, "The package of type " + packet.getClass().getName() + " is not handled by the server!");
+      return;
+    }
+
+    // update the socket data
+    socketData.unhandledTasks.incrementAndGet();
+    socketData.totalTasks.incrementAndGet();
+
+    // add the packet to the queue so it can be started by the worker
+    CompletableFuture.runAsync(() -> {
+      clientToServerPacket.onHandle(webSocket, this);
+      int remainingUnhandledTasks = socketData.unhandledTasks.decrementAndGet();
+
+      if (socketData.closeIfNoTasksLeft) {
+        // if the websocket has 0 unhandled Tasks, close the connection
+        if (remainingUnhandledTasks <= 0) {
+          sendMessage(webSocket, "All requested tasks finished! Closing connection...");
+          webSocket.close();
+        }
+      }
+    }, taskExecutor);
+  }
+
+  public void log(WebSocket webSocket, String msg) {
+    String socketId = (webSocket == null) ? "???" : webSocket.<SocketData>getAttachment().id;
+    logger.info("[" + socketId + "] " + msg);
+  }
+
+  /**
+   * The data that is associated server-side with any connected client.
+   * This makes it possible to store information that can be mapped to any existing connection.
+   */
+  public static class SocketData {
+
+    public final String id;
+    public final AtomicInteger unhandledTasks = new AtomicInteger(0);
+    public final AtomicInteger totalTasks = new AtomicInteger(0);
+    public boolean closeIfNoTasksLeft = false;
+
+    public SocketData(WebSocket webSocket) {
+      this.id = UUID.randomUUID().toString();
+      webSocket.setAttachment(this);
+    }
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/DebugPacket.java

@@ -0,0 +1,35 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialUUID;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
+import org.java_websocket.WebSocket;
+
+public class DebugPacket implements IClientToServerPacket.Void, IServerToClientPacket {
+
+  public SerialUUID a1;
+  public SerialUUID a2;
+  public SerialMap b1;
+  public SerialMap b2;
+  public SerialList<? extends ISerialNode> c1;
+  public SerialList<? extends ISerialNode> c2;
+  public SerialValue<?> d1;
+  public SerialValue<?> d2;
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketClient socketClient) {}
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketServer socketServer) {}
+
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/ErrorPacket.java

@@ -0,0 +1,36 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import org.java_websocket.WebSocket;
+
+/**
+ * A packet to send simple error messages between the client and the server
+ */
+public class ErrorPacket implements IServerToClientPacket {
+
+  /**
+   * The error endpoint for messages from the server that should be logged out as errors and possibly abort the process
+   */
+  public String error;
+  public boolean isFatal;
+
+  @JsonIgnore
+  public static ErrorPacket create(String error, boolean isFatal) {
+    ErrorPacket packet = new ErrorPacket();
+    packet.error = error;
+    packet.isFatal = isFatal;
+    return packet;
+  }
+
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketClient socketClient) {
+    SocketClient.logger.exception(new RuntimeException(this.error));
+    if (this.isFatal) {
+      socketClient.close(1, "Received fatal error from server");
+    }
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/IClientToServerPacket.java

@@ -0,0 +1,26 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import org.java_websocket.WebSocket;
+
+/**
+ * A packet that will be sent to the server. Use <code>Void</code> Sub-Interface for packets without response
+ *
+ * @param <T>   The response packet that will fulfill the future.
+ */
+public interface IClientToServerPacket<T extends IServerToClientPacket> extends IPacket {
+
+  @JsonIgnore
+  void onHandle(WebSocket webSocket, SocketServer socketServer);
+
+  @JsonIgnore
+  SocketFuture<T> getFuture();
+
+  /**
+   * Special case, where the packet will remain unanswered by the server
+   */
+  interface Void extends IClientToServerPacket<IServerToClientPacket> {}
+}
+

src/main/java/de/dhbwstuttgart/server/packet/IPacket.java

@@ -0,0 +1,12 @@
+package de.dhbwstuttgart.server.packet;
+
+/**
+ * The shared interface for all packet of the client-server connection.
+ * A packet must always:
+ * - Have a default / no-parameter constructor
+ * - Have only serializable public properties (or disable them via jackson annotations)
+ *
+ */
+public interface IPacket {
+
+}

src/main/java/de/dhbwstuttgart/server/packet/IServerToClientPacket.java

@@ -0,0 +1,12 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import org.java_websocket.WebSocket;
+
+public interface IServerToClientPacket extends IPacket {
+
+  @JsonIgnore
+  void onHandle(WebSocket webSocket, SocketClient socketClient);
+
+}

src/main/java/de/dhbwstuttgart/server/packet/InvalidPacket.java

@@ -0,0 +1,35 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import org.java_websocket.WebSocket;
+
+/**
+ * A fallback packet that is generated if the received JSON could not be mapped to an existing package
+ */
+public class InvalidPacket implements IClientToServerPacket.Void, IServerToClientPacket {
+
+  /**
+   * If available, the error that caused this package to appear
+   */
+  public String error = "<unknown error>";
+
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketClient socketClient) {
+    SocketClient.logger.error("InvalidPacket: " + this.error);
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketServer socketServer) {
+    socketServer.log(webSocket, "InvalidPacket: " + this.error);
+  }
+
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/MessagePacket.java

@@ -0,0 +1,40 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import org.java_websocket.WebSocket;
+
+/**
+ * A packet to send simple informational messages between the client and the server
+ */
+public class MessagePacket implements IClientToServerPacket.Void, IServerToClientPacket {
+
+  /**
+   * The informational message from the server that should be logged out outputted
+   */
+  public String message;
+
+  @JsonIgnore
+  public static MessagePacket create(String message) {
+    MessagePacket packet = new MessagePacket();
+    packet.message = message;
+    return packet;
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketClient socketClient) {
+    SocketClient.logger.info("SocketMessage: " + this.message);
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketServer socketServer) {
+    socketServer.log(webSocket, this.message);
+  }
+
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/PacketContainer.java

@@ -0,0 +1,98 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import de.dhbwstuttgart.util.Logger;
+
+/**
+ * A wrapper for the packet to ensure correct serialization/deserialization and make it possible to detect the matching
+ * packet type for deserialization.
+ */
+@JsonInclude(JsonInclude.Include.NON_NULL)
+public class PacketContainer {
+
+  // The jackson serializer / deserializer tool
+  private static final ObjectMapper objectMapper = new ObjectMapper();
+
+  /*
+   * The available packet types. The one type that is represented in the JSON should always be the ONLY non-null value.
+   * They have to be public (for the moment) to let jackson fill them in while deserializing
+   */
+  public ErrorPacket errorPacket = null;
+  public MessagePacket messagePacket = null;
+  public InvalidPacket invalidPacket = null;
+  public UnifyRequestPacket unifyRequestPacket = null;
+  public UnifyResultPacket unifyResultPacket = null;
+  public DebugPacket debugPacket = null;
+  public SetAutoclosePacket setAutoclosePacket = null;
+
+
+  /**
+   * Generate the JSON string for the given packet
+   *
+   * @param packet The packet to serialize
+   * @return The JSON representation of the packet
+   */
+  public static String serialize(IPacket packet) throws JsonProcessingException {
+    objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
+    PacketContainer container = new PacketContainer();
+
+    if (packet instanceof ErrorPacket)
+      container.errorPacket = (ErrorPacket) packet;
+    else if (packet instanceof MessagePacket)
+      container.messagePacket = (MessagePacket) packet;
+    else if (packet instanceof UnifyRequestPacket)
+      container.unifyRequestPacket = (UnifyRequestPacket) packet;
+    else if (packet instanceof UnifyResultPacket)
+      container.unifyResultPacket = (UnifyResultPacket) packet;
+    else if (packet instanceof DebugPacket)
+      container.debugPacket = (DebugPacket) packet;
+    else if (packet instanceof SetAutoclosePacket)
+      container.setAutoclosePacket = (SetAutoclosePacket) packet;
+    // Add new packets here and in the deserialize method
+    else
+      throw new RuntimeException("Cannot map packet to any known packet class");
+
+    return objectMapper.writeValueAsString(container);
+  }
+
+  /**
+   * Use the JSON string to generate the matching packet object
+   *
+   * @param json The serialized representation of a packet container
+   * @return The deserialized Packet object
+   */
+  public static IPacket deserialize(String json) {
+    objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
+
+    try {
+      PacketContainer container = objectMapper.readValue(json, PacketContainer.class);
+
+      if (container.errorPacket != null)
+        return container.errorPacket;
+      if (container.messagePacket != null)
+        return container.messagePacket;
+      if (container.invalidPacket != null)
+        return container.invalidPacket;
+      if (container.unifyRequestPacket != null)
+        return container.unifyRequestPacket;
+      if (container.unifyResultPacket != null)
+        return container.unifyResultPacket;
+      if (container.debugPacket != null)
+        return container.debugPacket;
+      if (container.setAutoclosePacket != null)
+        return container.setAutoclosePacket;
+      // Add new packets here and in the serialize method
+
+      throw new RuntimeException("Cannot map received json to any known packet class");
+    } catch (Exception e) {
+      (new Logger()).exception(e);
+      InvalidPacket packet = new InvalidPacket();
+      packet.error = e.getMessage();
+      return packet;
+    }
+  }
+
+
+}

src/main/java/de/dhbwstuttgart/server/packet/SetAutoclosePacket.java

@@ -0,0 +1,32 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import org.java_websocket.WebSocket;
+
+/**
+ * Normally, a connection stays open until either the client or the server process ends.
+ * Send this packet to inform the server that the connection can be closed once all tasks are done
+ */
+public class SetAutoclosePacket implements IClientToServerPacket.Void {
+
+  public int dummyProperty = 1;
+
+  @JsonIgnore
+  public static SetAutoclosePacket create() {
+    return new SetAutoclosePacket();
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketServer socketServer) {
+    webSocket.<SocketServer.SocketData>getAttachment().closeIfNoTasksLeft = true;
+    socketServer.log(webSocket, "Marked connection as autoclose");
+  }
+
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/UnifyRequestPacket.java

@@ -0,0 +1,164 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.core.ConsoleInterface;
+import de.dhbwstuttgart.server.ServerTaskLogger;
+import de.dhbwstuttgart.server.SocketFuture;
+import de.dhbwstuttgart.server.SocketServer;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
+import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
+import de.dhbwstuttgart.typeinference.constraints.Pair;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.typeinference.unify.TypeUnify;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.UnifyResultListenerImpl;
+import de.dhbwstuttgart.typeinference.unify.UnifyResultModel;
+import de.dhbwstuttgart.typeinference.unify.UnifyTaskModel;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.FiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyType;
+import de.dhbwstuttgart.util.Logger;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.concurrent.ForkJoinPool;
+import org.java_websocket.WebSocket;
+
+/**
+ * A packet to send all required data for the unification algorithm to the server and request the unification
+ */
+public class UnifyRequestPacket implements IClientToServerPacket<UnifyResultPacket> {
+
+  public SerialMap finiteClosure;
+  public SerialMap constraintSet;
+  public SerialMap unifyConstraintSet;
+  public SerialMap serialKeyStorage;
+  public SerialValue<?> placeholders;
+  public SerialList<SerialMap> factoryplaceholders;
+  public String futureId;
+  public int logLevel;
+
+  @JsonIgnore
+  private KeyStorage keyStorage = new KeyStorage();
+  @JsonIgnore
+  private boolean keyStorageLoaded = false;
+
+  public static UnifyRequestPacket create(
+    FiniteClosure finiteClosure,
+    ConstraintSet<Pair> constraintSet,
+    ConstraintSet<UnifyPair> unifyConstraintSet,
+    PlaceholderRegistry placeholderRegistry
+  ) {
+    UnifyRequestPacket packet = new UnifyRequestPacket();
+    // store constraint and finite closure
+    packet.finiteClosure = finiteClosure.toSerial(packet.keyStorage);
+    packet.constraintSet = constraintSet.toSerial(packet.keyStorage);
+    packet.unifyConstraintSet = unifyConstraintSet.toSerial(packet.keyStorage);
+    // store placeholder registry
+    var serialRegistry = placeholderRegistry.toSerial(packet.keyStorage);
+    packet.placeholders = serialRegistry.getValue("ph");
+    packet.factoryplaceholders = serialRegistry.getList("factoryPh").assertListOfMaps();
+    // store referenced objects separately
+    packet.serialKeyStorage = packet.keyStorage.toSerial(packet.keyStorage);
+    packet.logLevel = ConsoleInterface.logLevel.getValue();
+    return packet;
+  }
+
+
+  @JsonIgnore
+  public void loadKeyStorage(UnifyContext context) {
+    if (!keyStorageLoaded) {
+      keyStorageLoaded = true;
+      keyStorage = KeyStorage.fromSerial(this.serialKeyStorage, context);
+    }
+  }
+
+  @JsonIgnore
+  private FiniteClosure retrieveFiniteClosure(UnifyContext context) {
+    this.loadKeyStorage(context);
+    return FiniteClosure.fromSerial(this.finiteClosure, context, keyStorage);
+  }
+
+  @JsonIgnore
+  private ConstraintSet<Pair> retrieveConstraintSet(UnifyContext context) {
+    this.loadKeyStorage(context);
+    return ConstraintSet.fromSerial(this.constraintSet, context, Pair.class, keyStorage);
+  }
+
+  @JsonIgnore
+  private ConstraintSet<UnifyPair> retrieveUnifyConstraintSet(UnifyContext context) {
+    this.loadKeyStorage(context);
+    return ConstraintSet.fromSerial(this.unifyConstraintSet, context, UnifyPair.class, keyStorage);
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketServer socketServer) {
+    socketServer.sendMessage(webSocket, "You requested a unify! Please wait until I calculated everything...");
+    socketServer.log(webSocket, "Client requested a unification. Starting now...");
+
+    try {
+      var placeholderRegistry = new PlaceholderRegistry();
+      ArrayList<String> existingPlaceholders = (ArrayList) this.placeholders.getOf(ArrayList.class);
+      existingPlaceholders.forEach(placeholderRegistry::addPlaceholder);
+
+      Logger logger = new ServerTaskLogger(
+        webSocket,
+        socketServer,
+        Logger.LogLevel.fromValue(
+          Math.max(this.logLevel, Logger.LogLevel.INFO.getValue())
+        )
+      );
+      var unifyContext = new UnifyContext(logger, true,
+        new UnifyResultModel(new ConstraintSet<>(), new FiniteClosure(new HashSet<>(), logger, placeholderRegistry)),
+        new UnifyTaskModel(), ForkJoinPool.commonPool(), placeholderRegistry
+      );
+
+      this.factoryplaceholders.stream()
+        .map(p -> (PlaceholderType)UnifyType.fromSerial(p, unifyContext))
+        .forEach(placeholderRegistry.UnifyTypeFactory_PLACEHOLDERS::add);
+
+
+      // start the unification algorithm from the received data
+      IFiniteClosure finiteClosure = this.retrieveFiniteClosure(unifyContext);
+      ConstraintSet<Pair> constraintSet = this.retrieveConstraintSet(unifyContext);
+      ConstraintSet<UnifyPair> unifyConstraintSet = this.retrieveUnifyConstraintSet(unifyContext);
+
+      var resultModel = new UnifyResultModel(constraintSet, finiteClosure);
+      UnifyResultListenerImpl resultListener = new UnifyResultListenerImpl();
+      resultModel.addUnifyResultListener(resultListener);
+
+      TypeUnify.unifyParallel(
+        unifyConstraintSet.getUndConstraints(),
+        unifyConstraintSet.getOderConstraints(),
+        finiteClosure,
+        unifyContext.newWithResultModel(resultModel)
+      );
+
+      var resultSets = resultListener.getResults();
+
+      socketServer.log(webSocket, "Finished unification");
+      socketServer.sendMessage(webSocket, "Unification finished. Found " + resultSets.size() + " result sets");
+
+      if (webSocket.isOpen()) {
+        UnifyResultPacket resultPacket = UnifyResultPacket.create(resultSets, futureId);
+        webSocket.send(PacketContainer.serialize(resultPacket));
+      }
+    } catch (Exception e) {
+      SocketServer.logger.exception(e);
+      socketServer.log(webSocket, e.getMessage());
+    }
+  }
+
+  @JsonIgnore
+  public SocketFuture<UnifyResultPacket> getFuture() {
+    var future = new SocketFuture<>(List.of(UnifyResultPacket.class));
+    futureId = future.futureId;
+    return future;
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/UnifyResultPacket.java

@@ -0,0 +1,45 @@
+package de.dhbwstuttgart.server.packet;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.result.ResultSet;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import java.util.List;
+import org.java_websocket.WebSocket;
+
+/**
+ * A packet to send all calculated data from the unification algorithm back to the client
+ */
+public class UnifyResultPacket implements IServerToClientPacket {
+
+  public SerialList<ISerialNode> results;
+  public SerialMap keyStorage;
+  public String futureId;
+
+  public static UnifyResultPacket create(List<ResultSet> resultSets, String futureId) {
+    UnifyResultPacket serialized = new UnifyResultPacket();
+    KeyStorage keyStorage = new KeyStorage();
+    serialized.results = SerialList.fromMapped(resultSets, resultSet -> resultSet.toSerial(keyStorage));
+    serialized.keyStorage = keyStorage.toSerial(keyStorage);
+    serialized.futureId = futureId;
+    return serialized;
+  }
+
+  @JsonIgnore
+  public List<ResultSet> getResultSet(UnifyContext context) {
+    return this.results.assertListOfMaps().stream()
+      .map(resultData -> ResultSet.fromSerial(resultData, context)).toList();
+  }
+
+  @JsonIgnore
+  public void onHandle(WebSocket webSocket, SocketClient socketClient) {
+    SocketClient.logger.info("Received unify result");
+    socketClient.completeResponseFuture(futureId, this);
+  }
+
+
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/ISerializableData.java

@@ -0,0 +1,16 @@
+package de.dhbwstuttgart.server.packet.dataContainers;
+
+import de.dhbwstuttgart.exceptions.NotImplementedException;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+
+public interface ISerializableData {
+
+  public abstract ISerialNode toSerial(KeyStorage keyStorage);
+
+  public static Object fromSerial(SerialMap data, UnifyContext context) {
+    throw new NotImplementedException("Missing implementation of \"fromSerial\" for a serializable element");
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/KeyStorage.java

@@ -0,0 +1,103 @@
+package de.dhbwstuttgart.server.packet.dataContainers;
+
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class KeyStorage implements ISerializableData {
+
+  /**
+   *  Store a unique identifier for every element, so it can be referenced in the json
+   */
+  protected AtomicInteger identifierCount = new AtomicInteger();
+  /**
+   *  Store the serialized element per identifier when serializing
+   */
+  protected SerialMap serializedElements = new SerialMap();
+  /**
+   *  Store the unserialized element per identifier when unserializing
+   */
+  protected Map<String, ISerializableData> unserializedElements = new HashMap<>();
+
+
+  /**
+   *  Retrieve or generate a new identifier for a constraint
+   */
+  public String getIdentifier() {
+    return this.identifierCount.incrementAndGet() + "_";
+  }
+
+  /**
+   *  Checks if the given element identifier belongs to an element that was already serialized
+   */
+  public boolean isAlreadySerialized(String identifier) {
+    return this.serializedElements.containsKey(identifier);
+  }
+
+  /**
+   *  Checks if the given element identifier belongs to a element that was already unserialized
+   */
+  public boolean isAlreadyUnserialized(String identifier) {
+    return this.unserializedElements.containsKey(identifier);
+  }
+
+  /**
+   *  Register a serialized element to prevent it from being serialized again
+   */
+  public void putSerialized(String identifier, SerialMap serializedElement) {
+    this.serializedElements.put(identifier, serializedElement);
+  }
+
+  /**
+   *  Retrieve a serialized element
+   */
+  public SerialMap getSerialized(String identifier) {
+    if (!this.serializedElements.containsKey(identifier)) {
+      throw new RuntimeException("No serialized element of identifier " + identifier + " available to get");
+    }
+    return this.serializedElements.getMap(identifier);
+  }
+
+  /**
+   *  Register an unserialized element to prevent it from being unserialized again
+   */
+  public void putUnserialized(String identifier, ISerializableData element) {
+    this.unserializedElements.put(identifier, element);
+  }
+
+  /**
+   *  Retrieve an unserialized element
+   */
+  public <T extends ISerializableData> T getUnserialized(String identifier, Class<T> target) {
+    if (!this.unserializedElements.containsKey(identifier)) {
+      throw new RuntimeException("No unserialized element of identifier " + identifier + " available to get");
+    }
+    var element = this.unserializedElements.get(identifier);
+    if (target.isInstance(element)) {
+      return (T) element;
+    }
+    throw new RuntimeException("Failed to get unserialized element from KeyStorage. Expected instance of " +
+      target.getName() + " but found " + element.getClass().getName());
+  }
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("serializedElements", this.serializedElements);
+    return serialized;
+  }
+
+  public static KeyStorage fromSerial(SerialMap data, UnifyContext context) {
+    var serializedConstraintsData = data.getMap("serializedElements");
+    var constraintContext = new KeyStorage();
+    for (var entry : serializedConstraintsData.entrySet()) {
+      if (entry.getValue() instanceof SerialMap valueMap) {
+        constraintContext.putSerialized(entry.getKey(), valueMap);
+      }
+    }
+    return constraintContext;
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/serialized/ISerialNode.java

@@ -0,0 +1,31 @@
+package de.dhbwstuttgart.server.packet.dataContainers.serialized;
+
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
+
+
+/**
+ * Use the following classes for an intermediate serialized tree structure
+ */
+@JsonTypeInfo(
+  use = JsonTypeInfo.Id.NAME,
+  include = JsonTypeInfo.As.PROPERTY,
+  property = "_t"
+)
+@JsonSubTypes({
+  @JsonSubTypes.Type(value = SerialMap.class, name = "m"),
+  @JsonSubTypes.Type(value = SerialList.class, name = "l"),
+  @JsonSubTypes.Type(value = SerialValue.class, name = "v"),
+  @JsonSubTypes.Type(value = SerialUUID.class, name = "u")
+})
+public interface ISerialNode {
+
+  default <T extends ISerialNode> T assertType(Class<T> type) {
+    if (type.isInstance(this)) {
+      return (T) this;
+    }
+    throw new RuntimeException("Expected ISerialNode to be of type " + type.getName()
+      + " but found " + this.getClass().getName() + " instead");
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/serialized/SerialList.java

@@ -0,0 +1,74 @@
+package de.dhbwstuttgart.server.packet.dataContainers.serialized;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.function.Function;
+import java.util.stream.Stream;
+
+public class SerialList<I extends ISerialNode> extends ArrayList<I> implements ISerialNode {
+  public SerialList() {}
+  public SerialList(Collection<I> data) {
+    this.addAll(data);
+  }
+  public SerialList(Stream<I> data) {
+    this(data.toList());
+  }
+  public SerialList(I[] data) {
+    this(Arrays.stream(data).toList());
+  }
+
+  @SafeVarargs
+  @JsonIgnore
+  public static <A extends ISerialNode> ArrayList<A> from(A ...values) {
+    ArrayList<A> list = new SerialList<>();
+    Collections.addAll(list, values);
+    return list;
+  }
+  @JsonIgnore
+  public static <A,B extends ISerialNode> SerialList<B> fromMapped(Stream<A> data, Function<A,B> mapper) {
+    return new SerialList<>(data.map(mapper).toList());
+  }
+  @JsonIgnore
+  public static <A,B extends ISerialNode> SerialList<B> fromMapped(Collection<A> data, Function<A,B> mapper) {
+    return SerialList.fromMapped(data.stream(), mapper);
+  }
+  @JsonIgnore
+  public static <A,B extends ISerialNode> SerialList<B> fromMapped(A[] data, Function<A,B> mapper) {
+    return SerialList.fromMapped(Arrays.stream(data), mapper);
+  }
+
+  @JsonIgnore
+  public SerialList<SerialMap> assertListOfMaps() {
+    if (this.isEmpty() || this.get(0) instanceof SerialMap) {
+      return (SerialList<SerialMap>) this;
+    }
+    throw new RuntimeException("Required List to contain SerialMap elements but condition failed");
+  }
+
+  @JsonIgnore
+  public SerialList<SerialList<?>> assertListOfLists() {
+    if (this.isEmpty() || this.get(0) instanceof SerialList) {
+      return (SerialList<SerialList<?>>) this;
+    }
+    throw new RuntimeException("Required List to contain SerialList elements but condition failed");
+  }
+
+  @JsonIgnore
+  public SerialList<SerialValue<?>> assertListOfValues() {
+    if (this.isEmpty() || this.get(0) instanceof SerialValue) {
+      return (SerialList<SerialValue<?>>) this;
+    }
+    throw new RuntimeException("Required List to contain SerialValue elements but condition failed");
+  }
+
+  @JsonIgnore
+  public SerialList<SerialUUID> assertListOfUUIDs() {
+    if (this.isEmpty() || this.get(0) instanceof SerialUUID) {
+      return (SerialList<SerialUUID>) this;
+    }
+    throw new RuntimeException("Required List to contain SerialUUID elements but condition failed");
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/serialized/SerialMap.java

@@ -0,0 +1,84 @@
+package de.dhbwstuttgart.server.packet.dataContainers.serialized;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import java.util.HashMap;
+import java.util.Map;
+import javax.annotation.Nullable;
+
+public class SerialMap extends HashMap<String, ISerialNode> implements ISerialNode {
+
+  public SerialMap() {
+    super();
+  }
+
+  public SerialMap(Map<String, ISerialNode> data) {
+    super(data);
+  }
+
+  @JsonIgnore
+  public void put(String key, Boolean value) {
+    this.put(key, new SerialValue<>(value));
+  }
+
+  @JsonIgnore
+  public void put(String key, String value) {
+    this.put(key, new SerialValue<>(value));
+  }
+
+  @JsonIgnore
+  public void put(String key, Number value) {
+    this.put(key, new SerialValue<>(value));
+  }
+
+  @JsonIgnore
+  private <T> T get(String key, Class<T> expectedType) {
+    if (!this.containsKey(key)) {
+      throw new RuntimeException("Missing required value " + key + " in ObjectMap");
+    }
+    var element = this.get(key);
+    if (element != null && element.getClass() != expectedType) {
+      throw new RuntimeException(
+        "Required value " + key + " to be of type " + expectedType.getName() + " but found " + element.getClass().getName()
+      );
+    }
+    return (T)element;
+  }
+
+  @JsonIgnore
+  public SerialList<?> getList(String key) {
+    return this.get(key, SerialList.class);
+  }
+
+  @Nullable
+  @JsonIgnore
+  public SerialList<?> getListOrNull(String key) {
+    return this.containsKey(key) ? this.getList(key) : null;
+  }
+
+  @JsonIgnore
+  public SerialMap getMap(String key) {
+    return this.get(key, SerialMap.class);
+  }
+
+  @Nullable
+  @JsonIgnore
+  public SerialMap getMapOrNull(String key) {
+    return this.containsKey(key) ? this.getMap(key) : null;
+  }
+
+  @JsonIgnore
+  public SerialValue<?> getValue(String key) {
+    return this.get(key, SerialValue.class);
+  }
+
+  @JsonIgnore
+  public SerialUUID getUUID(String key) {
+    return this.get(key, SerialUUID.class);
+  }
+
+  @Nullable
+  @JsonIgnore
+  public SerialUUID getUUIDOrNull(String key) {
+    return this.containsKey(key) ? this.getUUID(key) : null;
+  }
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/serialized/SerialUUID.java

@@ -0,0 +1,13 @@
+package de.dhbwstuttgart.server.packet.dataContainers.serialized;
+
+public class SerialUUID implements ISerialNode {
+
+  public String uuid;
+
+  public SerialUUID() {}
+
+  public SerialUUID(String uuid) {
+    this.uuid = uuid;
+  }
+
+}

src/main/java/de/dhbwstuttgart/server/packet/dataContainers/serialized/SerialValue.java

@@ -0,0 +1,28 @@
+package de.dhbwstuttgart.server.packet.dataContainers.serialized;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+
+public class SerialValue<T> implements ISerialNode {
+  public T value;
+  public static final SerialValue<Object> NULL = new SerialValue<>(null);
+
+  public SerialValue() {}
+
+  public SerialValue(T value) {
+    this.value = value;
+  }
+
+  @JsonIgnore
+  public <A> SerialValue<A> assertValueOf(Class<A> targetClass) {
+    if (this.value == null || targetClass.isInstance(this.value)) {
+      return (SerialValue<A>) this;
+    }
+    throw new RuntimeException("Required Value to contain " + targetClass.getName() + " value but condition failed on" +
+      " type " + this.value.getClass().getName());
+  }
+
+  @JsonIgnore
+  public <A> A getOf(Class<A> targetClass) {
+    return this.assertValueOf(targetClass).value;
+  }
+}

src/main/java/de/dhbwstuttgart/syntaxtree/SyntaxTree.java

@@ -0,0 +1,8 @@
+package de.dhbwstuttgart.syntaxtree;
+
+import de.dhbwstuttgart.util.Logger;
+
+public class SyntaxTree {
+
+  public static Logger logger = new Logger("SyntaxTree");
+}

src/main/java/de/dhbwstuttgart/syntaxtree/factory/NameGenerator.java

@@ -1,5 +1,8 @@
 package de.dhbwstuttgart.syntaxtree.factory;
 
+import de.dhbwstuttgart.core.JavaTXCompiler;
+import de.dhbwstuttgart.core.JavaTXServer;
+
 public class NameGenerator {
 
     private static String strNextName = "A";
@@ -26,7 +29,11 @@ public class NameGenerator {
     
         // n�chster Name berechnen und in strNextName speichern        
         inc( strNextName.length() - 1 );
-        
+
+        if (JavaTXServer.isRunning) {
+            throw new RuntimeException("Using the NameGenerator on a server is not allowed");
+        }
+        JavaTXCompiler.defaultClientPlaceholderRegistry.addPlaceholder(strReturn);
         return strReturn;        
     }
 

src/main/java/de/dhbwstuttgart/syntaxtree/factory/UnifyTypeFactory.java

@@ -1,5 +1,8 @@
 package de.dhbwstuttgart.syntaxtree.factory;
 
+import de.dhbwstuttgart.syntaxtree.SyntaxTree;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.util.Logger;
 import java.io.Writer;
 import java.lang.reflect.Modifier;
 import java.util.*;
@@ -31,9 +34,13 @@ import org.antlr.v4.runtime.Token;
 
 public class UnifyTypeFactory {
 	
-	private static ArrayList<PlaceholderType> PLACEHOLDERS = new ArrayList<>(); 
-
-    public static FiniteClosure generateFC(List<ClassOrInterface> fromClasses, Writer logFile, ClassLoader classLoader, JavaTXCompiler compiler) throws ClassNotFoundException {
+    public static FiniteClosure generateFC(
+      List<ClassOrInterface> fromClasses,
+      Logger logger,
+      ClassLoader classLoader,
+      JavaTXCompiler compiler,
+      PlaceholderRegistry placeholderRegistry
+    ) throws ClassNotFoundException {
         /*
         Die transitive Hülle muss funktionieren.
         Man darf schreiben List<A> extends AL<A>
@@ -44,7 +51,7 @@ public class UnifyTypeFactory {
         Generell dürfen sie immer die gleichen Namen haben.
         TODO: die transitive Hülle bilden
          */
-        return new FiniteClosure(FCGenerator.toUnifyFC(compiler, fromClasses, classLoader), logFile, compiler);
+        return new FiniteClosure(FCGenerator.toUnifyFC(compiler, fromClasses, classLoader, placeholderRegistry), logger, compiler, placeholderRegistry);
     }
 
     public static UnifyPair generateSmallerPair(UnifyType tl, UnifyType tr, SourceLoc location){
@@ -67,23 +74,23 @@ public class UnifyTypeFactory {
      * Convert from
      * ASTType -> UnifyType
      */
-    public static UnifyType convert(JavaTXCompiler compiler, RefTypeOrTPHOrWildcardOrGeneric t, Boolean innerType){
+    public static UnifyType convert(JavaTXCompiler compiler, RefTypeOrTPHOrWildcardOrGeneric t, Boolean innerType, PlaceholderRegistry placeholderRegistry){
         if (t instanceof GenericRefType){
-            return UnifyTypeFactory.convert(compiler, (GenericRefType)t, innerType);
+            return UnifyTypeFactory.convert(compiler, (GenericRefType)t, innerType, placeholderRegistry);
         } else if (t instanceof TypePlaceholder){
-            return UnifyTypeFactory.convert(compiler, (TypePlaceholder)t, innerType);
+            return UnifyTypeFactory.convert(compiler, (TypePlaceholder)t, innerType, placeholderRegistry);
         } else if (t instanceof ExtendsWildcardType){
-            return UnifyTypeFactory.convert(compiler, (ExtendsWildcardType)t, innerType);
+            return UnifyTypeFactory.convert(compiler, (ExtendsWildcardType)t, innerType, placeholderRegistry);
         } else if (t instanceof SuperWildcardType) {
-            return UnifyTypeFactory.convert(compiler, (SuperWildcardType) t, innerType);
+            return UnifyTypeFactory.convert(compiler, (SuperWildcardType) t, innerType, placeholderRegistry);
         } else if (t instanceof RefType){
-            return UnifyTypeFactory.convert(compiler, (RefType)t, innerType);
+            return UnifyTypeFactory.convert(compiler, (RefType)t, innerType, placeholderRegistry);
         }
         //Es wurde versucht ein Typ umzuwandeln, welcher noch nicht von der Factory abgedeckt ist
         throw new NotImplementedException("Der Typ "+t+" kann nicht umgewandelt werden");
     }
 
-    public static UnifyType convert(JavaTXCompiler compiler, RefType t, Boolean innerType){
+    public static UnifyType convert(JavaTXCompiler compiler, RefType t, Boolean innerType, PlaceholderRegistry placeholderRegistry){
         //Check if it is a FunN Type:
         Pattern p = Pattern.compile("Fun(\\d+)[$][$]");
         Matcher m = p.matcher(t.getName().toString());
@@ -91,76 +98,76 @@ public class UnifyTypeFactory {
         if(b){
             Integer N = Integer.valueOf(m.group(1));
             if((N + 1) == t.getParaList().size()){
-                return convertFunN(compiler, t.getParaList(), false);
+                return convertFunN(compiler, t.getParaList(), false, placeholderRegistry);
             }
         }
         UnifyType ret;
         List<UnifyType> params = new ArrayList<>();
         if (t.getParaList() != null) {
             for (RefTypeOrTPHOrWildcardOrGeneric pT : t.getParaList()) {
-                params.add(UnifyTypeFactory.convert(compiler, pT, true));
+                params.add(UnifyTypeFactory.convert(compiler, pT, true, placeholderRegistry));
             }
         }
 
         var clazz = compiler.getClass(t.getName());
         if (clazz != null && clazz.isInterface() && clazz.isFunctionalInterface()) {
             var method = clazz.getMethods().stream().filter(x -> Modifier.isAbstract(x.modifier)).findFirst().orElseThrow();
-            var methodParams = method.getParameterList().getFormalparalist().stream().map(x -> convert(compiler, x.getType(), true)).toList();
+            var methodParams = method.getParameterList().getFormalparalist().stream().map(x -> convert(compiler, x.getType(), true, placeholderRegistry)).toList();
             var generics = StreamSupport.stream(clazz.getGenerics().spliterator(), false).map(GenericTypeVar::getName).toList();
-            return new FunInterfaceType(t.getName().toString(), new TypeParams(params), methodParams, convert(compiler, method.getReturnType(), true), generics);
+            return new FunInterfaceType(t.getName().toString(), new TypeParams(params), methodParams, convert(compiler, method.getReturnType(), true, placeholderRegistry), generics);
         }
 
         return new ReferenceType(t.getName().toString(),new TypeParams(params));
     }
 
-    public static UnifyType convertFunN(JavaTXCompiler compiler, List<RefTypeOrTPHOrWildcardOrGeneric> paraList, Boolean innerType){
+    public static UnifyType convertFunN(JavaTXCompiler compiler, List<RefTypeOrTPHOrWildcardOrGeneric> paraList, Boolean innerType, PlaceholderRegistry placeholderRegistry){
         UnifyType ret;
         List<UnifyType> params = new ArrayList<>();
         if(paraList != null && paraList.size() > 0){
             for(RefTypeOrTPHOrWildcardOrGeneric pT : paraList){
-                params.add(UnifyTypeFactory.convert(compiler, pT, false));
+                params.add(UnifyTypeFactory.convert(compiler, pT, false, placeholderRegistry));
             }
         }
         ret = FunNType.getFunNType(new TypeParams(params));
         return ret;
     }
 
-    public static UnifyType convert(JavaTXCompiler compiler, TypePlaceholder tph, Boolean innerType){
+    public static UnifyType convert(JavaTXCompiler compiler, TypePlaceholder tph, Boolean innerType, PlaceholderRegistry placeholderRegistry) {
     	if (tph.getName().equals("AFR")) {
-    		System.out.println("XXX"+innerType);
+          SyntaxTree.logger.info("XXX"+innerType);
     	}
-    	PlaceholderType ntph = new PlaceholderType(tph.getName(), tph.getVariance());
+    	PlaceholderType ntph = new PlaceholderType(tph.getName(), tph.getVariance(), placeholderRegistry);
     	ntph.setVariance(tph.getVariance());
     	ntph.setOrCons(tph.getOrCons());
     	ntph.setWildcardtable(tph.getWildcardtable());
-    	int in = PLACEHOLDERS.indexOf(ntph);
+    	int in = placeholderRegistry.UnifyTypeFactory_PLACEHOLDERS.indexOf(ntph);
 		if (in == -1) {
-			PLACEHOLDERS.add(ntph);
+        placeholderRegistry.UnifyTypeFactory_PLACEHOLDERS.add(ntph);
 			ntph.setInnerType(innerType);
 			return ntph;
 		}
 		else {
-			 PlaceholderType oldpht = PLACEHOLDERS.get(in);
+			 PlaceholderType oldpht = placeholderRegistry.UnifyTypeFactory_PLACEHOLDERS.get(in);
 			 oldpht.setInnerType(oldpht.isInnerType() || innerType);
 			 return oldpht;
 		}
     }
 
-    public static UnifyType convert(JavaTXCompiler compiler, GenericRefType t, Boolean innerType){
+    public static UnifyType convert(JavaTXCompiler compiler, GenericRefType t, Boolean innerType, PlaceholderRegistry placeholderRegistry){
         return new ReferenceType(t.getParsedName(), true);
     }
 
-    public static UnifyType convert(JavaTXCompiler compiler, WildcardType t, Boolean innerType){
+    public static UnifyType convert(JavaTXCompiler compiler, WildcardType t, Boolean innerType, PlaceholderRegistry placeholderRegistry){
         if(t.isExtends())
-            return new ExtendsType(UnifyTypeFactory.convert(compiler, t.getInnerType(), false));
+            return new ExtendsType(UnifyTypeFactory.convert(compiler, t.getInnerType(), false, placeholderRegistry));
         else if(t.isSuper())
-            return new SuperType(UnifyTypeFactory.convert(compiler, t.getInnerType(), false));
+            return new SuperType(UnifyTypeFactory.convert(compiler, t.getInnerType(), false, placeholderRegistry));
         else throw new NotImplementedException();
     }
 
 
-    public static ConstraintSet<UnifyPair> convert(JavaTXCompiler compiler, ConstraintSet<Pair> constraints) {
-        return constraints.map(c -> UnifyTypeFactory.convert(compiler, c));
+    public static ConstraintSet<UnifyPair> convert(JavaTXCompiler compiler, ConstraintSet<Pair> constraints, PlaceholderRegistry placeholderRegistry) {
+        return constraints.map(c -> UnifyTypeFactory.convert(compiler, c, placeholderRegistry));
     }
 
     //NEVER USED
@@ -171,30 +178,30 @@ public class UnifyTypeFactory {
     //	return unifyPairConstraint;
     //}
 
-    public static UnifyPair convert(JavaTXCompiler compiler, Pair p) {
+    public static UnifyPair convert(JavaTXCompiler compiler, Pair p, PlaceholderRegistry placeholderRegistry) {
     	UnifyPair ret = null;
         if(p.GetOperator().equals(PairOperator.SMALLERDOT)) {
-             ret = generateSmallerDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false)
-                    , UnifyTypeFactory.convert(compiler, p.TA2, false), p.getLocation());
+             ret = generateSmallerDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false, placeholderRegistry)
+                    , UnifyTypeFactory.convert(compiler, p.TA2, false, placeholderRegistry), p.getLocation());
             //return ret;
         }else if(p.GetOperator().equals(PairOperator.SMALLERNEQDOT)) {
-             ret = generateSmallNotEqualDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false)
-                    , UnifyTypeFactory.convert(compiler, p.TA2, false), p.getLocation());
+             ret = generateSmallNotEqualDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false, placeholderRegistry)
+                    , UnifyTypeFactory.convert(compiler, p.TA2, false, placeholderRegistry), p.getLocation());
             //return ret;
         }else if(p.GetOperator().equals(PairOperator.EQUALSDOT)) {
-             ret = generateEqualDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false)
-                    , UnifyTypeFactory.convert(compiler, p.TA2, false), p.getLocation());
+             ret = generateEqualDotPair(UnifyTypeFactory.convert(compiler, p.TA1, false, placeholderRegistry)
+                    , UnifyTypeFactory.convert(compiler, p.TA2, false, placeholderRegistry), p.getLocation());
             //return ret;
         }else if(p.GetOperator().equals(PairOperator.SMALLER)){
-            ret =  generateSmallerPair(UnifyTypeFactory.convert(compiler, p.TA1, false),
-                    UnifyTypeFactory.convert(compiler, p.TA2, false), p.getLocation());
+            ret =  generateSmallerPair(UnifyTypeFactory.convert(compiler, p.TA1, false, placeholderRegistry),
+                    UnifyTypeFactory.convert(compiler, p.TA2, false, placeholderRegistry), p.getLocation());
         }else            throw new NotImplementedException();
         UnifyType lhs, rhs;
         if (((lhs = ret.getLhsType()) instanceof PlaceholderType) 
         		&& ((PlaceholderType)lhs).isWildcardable() 
         		&&	(rhs = ret.getLhsType()) instanceof PlaceholderType) {
         	if (lhs.getName().equals("AQ")) {
-        		System.out.println("");
+        		// SyntaxTree.logger.info("");
         	}
         	((PlaceholderType)rhs).enableWildcardtable();
         }
@@ -203,7 +210,7 @@ public class UnifyTypeFactory {
         		&& ((PlaceholderType)rhs).isWildcardable()
         		&&	(lhs = ret.getLhsType()) instanceof PlaceholderType) {
         	if (rhs.getName().equals("AQ")) {
-        		System.out.println("");
+        		// SyntaxTree.logger.info("");
         	}
         	((PlaceholderType)lhs).enableWildcardtable();
         }
@@ -214,16 +221,16 @@ public class UnifyTypeFactory {
      * Convert from
      * UnifyType -> ASTType
      */
-    public static Set<ResultPair> convert(Set<UnifyPair> unifyPairSet, Map<String,TypePlaceholder> tphs) {
+    public static Set<ResultPair> convert(Set<UnifyPair> unifyPairSet, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
         return unifyPairSet.stream().map(
-                unifyPair -> convert(unifyPair, tphs))
+                unifyPair -> convert(unifyPair, tphs, placeholderRegistry))
                         .collect(Collectors.toSet());
     }
 
-    public static ResultPair convert(UnifyPair mp, Map<String,TypePlaceholder> tphs) {
+    public static ResultPair convert(UnifyPair mp, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
     	if (mp == null) { return null;} //kann bei basePairs passieren
-        RefTypeOrTPHOrWildcardOrGeneric tl = UnifyTypeFactory.convert(mp.getLhsType(), tphs);
-        RefTypeOrTPHOrWildcardOrGeneric tr = UnifyTypeFactory.convert(mp.getRhsType(), tphs);
+        RefTypeOrTPHOrWildcardOrGeneric tl = UnifyTypeFactory.convert(mp.getLhsType(), tphs, placeholderRegistry);
+        RefTypeOrTPHOrWildcardOrGeneric tr = UnifyTypeFactory.convert(mp.getRhsType(), tphs, placeholderRegistry);
         if(tl instanceof TypePlaceholder){
             if(tr instanceof TypePlaceholder) {
 
@@ -232,7 +239,7 @@ public class UnifyTypeFactory {
                     //Einfach ignorieren TODO: Das hier muss ausgebessert werden:
                     //return new PairTPHequalRefTypeOrWildcardType((TypePlaceholder)tl, ASTFactory.createObjectType());
                 }else{
-                    return new PairTPHsmallerTPH((TypePlaceholder)tl, (TypePlaceholder)tr, convert(mp.getBasePair(), tphs));
+                    return new PairTPHsmallerTPH((TypePlaceholder)tl, (TypePlaceholder)tr, convert(mp.getBasePair(), tphs, placeholderRegistry));
                 }
             }else if(tr instanceof RefType){
                 return new PairTPHequalRefTypeOrWildcardType((TypePlaceholder)tl, (RefType) tr);
@@ -244,51 +251,51 @@ public class UnifyTypeFactory {
         }else return new PairNoResult(tl, tr);//throw new NotImplementedException();
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(ReferenceType t, Map<String,TypePlaceholder> tphs) {
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(ReferenceType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
         if(JavaClassName.Void.equals(t.getName()))return new Void(new NullToken());
         if (t.isGenTypeVar()) return new GenericRefType(t.getName(),new NullToken());
-        RefType ret = new RefType(new JavaClassName(t.getName()),convert(t.getTypeParams(), tphs),new NullToken());
+        RefType ret = new RefType(new JavaClassName(t.getName()),convert(t.getTypeParams(), tphs, placeholderRegistry),new NullToken());
         return ret;
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(FunNType t, Map<String,TypePlaceholder> tphs) {
-        RefType ret = new RefType(new JavaClassName(t.getName()), convert(t.getTypeParams(), tphs), new NullToken());
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(FunNType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
+        RefType ret = new RefType(new JavaClassName(t.getName()), convert(t.getTypeParams(), tphs, placeholderRegistry), new NullToken());
         return ret;
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(SuperType t, Map<String,TypePlaceholder> tphs) {
-        RefTypeOrTPHOrWildcardOrGeneric innerType = convert(t.getSuperedType(), tphs);
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(SuperType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
+        RefTypeOrTPHOrWildcardOrGeneric innerType = convert(t.getSuperedType(), tphs, placeholderRegistry);
         return new SuperWildcardType(innerType, new NullToken());
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(ExtendsType t, Map<String,TypePlaceholder> tphs) {
-        RefTypeOrTPHOrWildcardOrGeneric innerType = convert(t.getExtendedType(), tphs);
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(ExtendsType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
+        RefTypeOrTPHOrWildcardOrGeneric innerType = convert(t.getExtendedType(), tphs, placeholderRegistry);
         return new ExtendsWildcardType(innerType, new NullToken());
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(PlaceholderType t, Map<String,TypePlaceholder> tphs) {
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(PlaceholderType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
         TypePlaceholder ret = tphs.get(t.getName());
         if(ret == null){ //Dieser TPH wurde vom Unifikationsalgorithmus erstellt
-            ret = TypePlaceholder.fresh(new NullToken());
+            ret = TypePlaceholder.fresh(new NullToken(), placeholderRegistry);
             tphs.put(t.getName(), ret);
         }
         ret.setVariance(t.getVariance());
         return ret;
     }
 
-    public static RefTypeOrTPHOrWildcardOrGeneric convert(UnifyType t, Map<String,TypePlaceholder> tphs) {
-        if(t instanceof FunNType)return convert((FunNType) t, tphs);
-        if(t instanceof ReferenceType)return convert((ReferenceType) t, tphs);
-        if(t instanceof SuperType)return convert((SuperType) t, tphs);
-        if(t instanceof ExtendsType)return convert((ExtendsType) t, tphs);
-        if(t instanceof PlaceholderType)return convert((PlaceholderType) t, tphs);
+    public static RefTypeOrTPHOrWildcardOrGeneric convert(UnifyType t, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
+        if(t instanceof FunNType)return convert((FunNType) t, tphs, placeholderRegistry);
+        if(t instanceof ReferenceType)return convert((ReferenceType) t, tphs, placeholderRegistry);
+        if(t instanceof SuperType)return convert((SuperType) t, tphs, placeholderRegistry);
+        if(t instanceof ExtendsType)return convert((ExtendsType) t, tphs, placeholderRegistry);
+        if(t instanceof PlaceholderType)return convert((PlaceholderType) t, tphs, placeholderRegistry);
         throw new NotImplementedException("Der Typ "+t+" kann nicht umgewandelt werden");
     }
 
-    private static List<RefTypeOrTPHOrWildcardOrGeneric> convert(TypeParams typeParams, Map<String,TypePlaceholder> tphs) {
+    private static List<RefTypeOrTPHOrWildcardOrGeneric> convert(TypeParams typeParams, Map<String,TypePlaceholder> tphs, PlaceholderRegistry placeholderRegistry) {
         List<RefTypeOrTPHOrWildcardOrGeneric> ret = new ArrayList<>();
         for(UnifyType uT : typeParams){
-            RefTypeOrTPHOrWildcardOrGeneric toAdd = convert(uT, tphs);
+            RefTypeOrTPHOrWildcardOrGeneric toAdd = convert(uT, tphs, placeholderRegistry);
             ret.add(toAdd);
         }
         return ret;

src/main/java/de/dhbwstuttgart/syntaxtree/type/ExtendsWildcardType.java

@@ -1,8 +1,13 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
 
+import de.dhbwstuttgart.parser.NullToken;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
 import java.util.Objects;
@@ -15,7 +20,7 @@ import java.util.Objects;
  * 
  */
 
-public class ExtendsWildcardType extends WildcardType{
+public class ExtendsWildcardType extends WildcardType implements ISerializableData {
 	
 	/**
 	* Author: Arne Lüdtke<br/>
@@ -68,4 +73,22 @@ public class ExtendsWildcardType extends WildcardType{
 		ExtendsWildcardType that = (ExtendsWildcardType) o;
 		return that.innerType.equals(this.innerType);
 	}
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("innerType", this.innerType.toSerial(keyStorage));
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static ExtendsWildcardType fromSerial(SerialMap data, UnifyContext context) {
+		return new ExtendsWildcardType(
+			RefTypeOrTPHOrWildcardOrGeneric.fromSerial(data.getMap("innerType"), context),
+			new NullToken()
+		);
+	}
 }

src/main/java/de/dhbwstuttgart/syntaxtree/type/GenericRefType.java

@@ -1,57 +1,77 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
+import de.dhbwstuttgart.parser.NullToken;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
 import java.util.Objects;
 
-public class GenericRefType extends RefTypeOrTPHOrWildcardOrGeneric
-{
-    private String name;
+public class GenericRefType extends RefTypeOrTPHOrWildcardOrGeneric implements ISerializableData {
+  private String name;
 
-    public GenericRefType(String name, Token offset)
-    {
-        super(offset);
-        this.name = name;
-    }
+  public GenericRefType(String name, Token offset) {
+    super(offset);
+    this.name = name;
+  }
 
-    public String getParsedName(){
-        return name.toString();
-    }
+  public String getParsedName() {
+    return name.toString();
+  }
 
-    @Override
-    public void accept(ASTVisitor visitor) {
-        visitor.visit(this);
-    }
+  @Override
+  public void accept(ASTVisitor visitor) {
+    visitor.visit(this);
+  }
 
-    @Override
-    public <A> A acceptTV(TypeVisitor<A> visitor) {
-        return visitor.visit(this);
-    }
+  @Override
+  public <A> A acceptTV(TypeVisitor<A> visitor) {
+    return visitor.visit(this);
+  }
 
-    @Override
-    public void accept(ResultSetVisitor visitor) {
-        visitor.visit(this);
-    }
+  @Override
+  public void accept(ResultSetVisitor visitor) {
+    visitor.visit(this);
+  }
 
-    @Override
-    public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-        GenericRefType that = (GenericRefType) o;
-        return name.equals(that.name);
-    }
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    GenericRefType that = (GenericRefType) o;
+    return name.equals(that.name);
+  }
 
-    @Override
-    public int hashCode() {
-        return Objects.hash(name);
-    }
+  @Override
+  public int hashCode() {
+    return Objects.hash(name);
+  }
 
-    @Override
-	public String toString()
-	{
-		 return "GTV " + this.name;
-	}
+  @Override
+  public String toString() {
+    return "GTV " + this.name;
+  }
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("name", this.name);
+
+    // create the wrapper and put this as the object
+    var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+    serializedWrapper.put("object", serialized);
+    return serializedWrapper;
+  }
+
+  public static GenericRefType fromSerial(SerialMap data, UnifyContext context) {
+    return new GenericRefType(
+      data.getValue("name").getOf(String.class),
+      new NullToken()
+    );
+  }
 }
 

src/main/java/de/dhbwstuttgart/syntaxtree/type/RefType.java

@@ -1,8 +1,15 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
+import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.parser.scope.JavaClassName;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
 import java.util.ArrayList;
@@ -11,122 +18,137 @@ import java.util.List;
 import java.util.Objects;
 
 
-public class RefType extends RefTypeOrTPHOrWildcardOrGeneric
-{
-	protected final JavaClassName name;
-    protected final List<RefTypeOrTPHOrWildcardOrGeneric> parameter;
-    /**
-     * Ist primitiveFlag auf true, muss beim Codegen dieser Reftype durch
-     * den primitiven Datentyp ersetzt werden
-     *
-     * Bsp: java.lang.Integer mit Flag wird dann zu [int]
-     */
-    boolean primitiveFlag = false; // TODO Should be final
+public class RefType extends RefTypeOrTPHOrWildcardOrGeneric implements ISerializableData {
+  protected final JavaClassName name;
+  protected final List<RefTypeOrTPHOrWildcardOrGeneric> parameter;
+  /**
+   * Ist primitiveFlag auf true, muss beim Codegen dieser Reftype durch
+   * den primitiven Datentyp ersetzt werden
+   * <p>
+   * Bsp: java.lang.Integer mit Flag wird dann zu [int]
+   */
+  boolean primitiveFlag = false; // TODO Should be final
 
-    public RefType(JavaClassName fullyQualifiedName, Token offset)
-    {
-        this(fullyQualifiedName, new ArrayList<>(), offset);
+  public RefType(JavaClassName fullyQualifiedName, Token offset) {
+    this(fullyQualifiedName, new ArrayList<>(), offset);
+  }
+
+  public boolean isPrimitive() {
+    return primitiveFlag;
+  }
+
+  @Override
+  public String toString() {
+    String params = "";
+    if (parameter.size() > 0) {
+      params += "<";
+      Iterator<RefTypeOrTPHOrWildcardOrGeneric> it = parameter.iterator();
+      while (it.hasNext()) {
+        RefTypeOrTPHOrWildcardOrGeneric param = it.next();
+        params += param.toString();
+        if (it.hasNext()) params += ", ";
+      }
+      params += ">";
+    }
+    return this.name.toString() + params;
+  }
+
+  @Override
+  public int hashCode() {
+    return this.name.hashCode();//Nur den Name hashen. Sorgt für langsame, aber funktionierende HashMaps
+  }
+
+  public RefType(JavaClassName fullyQualifiedName, List<RefTypeOrTPHOrWildcardOrGeneric> parameter, Token offset) {
+    this(fullyQualifiedName, parameter, offset, false);
+  }
+
+  public RefType(JavaClassName fullyQualifiedName, List<RefTypeOrTPHOrWildcardOrGeneric> parameter, Token offset, boolean primitiveFlag) {
+    super(offset);
+    this.name = (fullyQualifiedName);
+    this.parameter = parameter;
+    this.primitiveFlag = primitiveFlag;
+  }
+
+  public JavaClassName getName() {
+    return name;
+  }
+
+  public List<RefTypeOrTPHOrWildcardOrGeneric> getParaList() {
+    if (this.parameter == null) return new ArrayList<>();
+    return this.parameter;
+  }
+
+  /**
+   * Author: Jrg Buerle<br/>
+   *
+   * @return
+   */
+  public boolean equals(Object obj) {
+    if (!(obj instanceof RefType refObj)) {
+      return false;
     }
 
-    public boolean isPrimitive() {
-        return primitiveFlag;
-    }
+    if (!Objects.equals(this.name, refObj.name)) return false;
+    boolean ret = true;
 
-    @Override
-    public String toString(){
-        String params = "";
-        if(parameter.size()>0){
-            params += "<";
-            Iterator<RefTypeOrTPHOrWildcardOrGeneric> it = parameter.iterator();
-            while(it.hasNext()){
-                RefTypeOrTPHOrWildcardOrGeneric param = it.next();
-                params += param.toString();
-                if(it.hasNext())params += ", ";
-            }
-            params += ">";
+    //if(!(super.equals(obj))) PL 2020-03-12 muss vll. einkommentiert werden
+    //	return false;
+
+    if (parameter == null || parameter.size() == 0) {
+      ret &= (refObj.getParaList() == null || refObj.getParaList().isEmpty());
+    } else {
+      if (refObj.getParaList() == null) {
+        ret = false;
+      } else if (parameter.size() != refObj.getParaList().size()) {
+        ret = false;
+      } else {
+        for (int i = 0; i < parameter.size(); i++) {
+          ret &= parameter.get(i).equals(refObj.getParaList().get(i));
         }
-        return this.name.toString() + params;
+      }
     }
+    return ret;
 
-    @Override
-	public int hashCode() {
-        return this.name.hashCode();//Nur den Name hashen. Sorgt für langsame, aber funktionierende HashMaps
-	}
+  }
 
-    public RefType(JavaClassName fullyQualifiedName, List<RefTypeOrTPHOrWildcardOrGeneric> parameter, Token offset) {
-        this(fullyQualifiedName, parameter, offset, false);
-    }
 
-    public RefType(JavaClassName fullyQualifiedName, List<RefTypeOrTPHOrWildcardOrGeneric> parameter, Token offset, boolean primitiveFlag) {
-        super(offset);
-        this.name = (fullyQualifiedName);
-        this.parameter = parameter;
-        this.primitiveFlag = primitiveFlag;
-    }
+  @Override
+  public void accept(ASTVisitor visitor) {
+    visitor.visit(this);
+  }
 
-    public JavaClassName getName()
-    {
-        return name;
-    }
+  @Override
+  public <A> A acceptTV(TypeVisitor<A> visitor) {
+    return visitor.visit(this);
+  }
 
-    public List<RefTypeOrTPHOrWildcardOrGeneric> getParaList(){
-    	if(this.parameter==null)return new ArrayList<>();
-    	return this.parameter;
-    }
+  @Override
+  public void accept(ResultSetVisitor visitor) {
+    visitor.visit(this);
+  }
 
-    /**
-     * Author: Jrg Buerle<br/>
-     * @return
-     */
-    public boolean equals(Object obj)
-    {
-        if(obj instanceof RefType){
-            if (!Objects.equals(this.name, ((RefType) obj).name)) return false;
-            boolean ret = true;
-            
-            //if(!(super.equals(obj))) PL 2020-03-12 muss vll. einkommentiert werden   
-            //	return false;
-            
-            if(parameter==null || parameter.size()==0){
-                ret &= (((RefType)obj).getParaList()==null || ((RefType)obj).getParaList().size()==0);
-            }
-            else{
-                if(((RefType)obj).getParaList()==null){
-                    ret = false;
-                }
-                else if(parameter.size() != ((RefType)obj).getParaList().size())
-                {
-                	ret = false;
-                }
-                else
-                {
-                	for(int i = 0; i<parameter.size(); i++)
-                	{
-                		ret &= parameter.get(i).equals(((RefType)obj).getParaList().get(i));
-                	}
-                }
-            }
-            return ret;
-        }
-        else{
-            return false;
-        }
-    }
-    	
+  @Override
+  public ISerialNode toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("isPrimitive", this.primitiveFlag);
+    serialized.put("name", this.name.toString());
+    serialized.put("parameters", SerialList.fromMapped(this.parameter, param -> param.toSerial(keyStorage)));
 
-    @Override
-    public void accept(ASTVisitor visitor) {
-        visitor.visit(this);
-    }
+    // create the wrapper and put this as the object
+    var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+    serializedWrapper.put("object", serialized);
+    return serializedWrapper;
+  }
 
-    @Override
-    public <A> A acceptTV(TypeVisitor<A> visitor) {
-        return visitor.visit(this);
-    }
-
-    @Override
-    public void accept(ResultSetVisitor visitor) {
-        visitor.visit(this);
-    }
+  public static RefType fromSerial(SerialMap data, UnifyContext context) {
+    return new RefType(
+      new JavaClassName(data.getValue("name").getOf(String.class)),
+      data.getList("parameters").assertListOfMaps().stream()
+        .map(param -> RefTypeOrTPHOrWildcardOrGeneric.fromSerial(param, context))
+        .toList(),
+      new NullToken(),
+      data.getValue("isPrimitive").getOf(Boolean.class)
+    );
+  }
 }
 

src/main/java/de/dhbwstuttgart/syntaxtree/type/RefTypeOrTPHOrWildcardOrGeneric.java

@@ -1,11 +1,17 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
 import de.dhbwstuttgart.syntaxtree.SyntaxTreeNode;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
-public abstract class RefTypeOrTPHOrWildcardOrGeneric extends SyntaxTreeNode{
+public abstract class RefTypeOrTPHOrWildcardOrGeneric extends SyntaxTreeNode implements ISerializableData {
     public RefTypeOrTPHOrWildcardOrGeneric(Token offset) {
         super(offset);
     }
@@ -18,5 +24,26 @@ public abstract class RefTypeOrTPHOrWildcardOrGeneric extends SyntaxTreeNode{
     
     @Override
     public abstract boolean equals(Object o);
-    
+
+    @Override
+    public ISerialNode toSerial(KeyStorage keyStorage) {
+        SerialMap serialized = new SerialMap();
+        serialized.put("type", this.getClass().getSimpleName());
+          // we only insert null for the object and expect the child classes to call this and override the value with themselves
+        serialized.put("object", SerialValue.NULL);
+        return serialized;
+    }
+
+    public static RefTypeOrTPHOrWildcardOrGeneric fromSerial(SerialMap data, UnifyContext context) {
+        String type = data.getValue("type").getOf(String.class);
+        SerialMap object = data.getMap("object");
+
+        if      (type.equals(ExtendsWildcardType.class.getSimpleName()))    return ExtendsWildcardType.fromSerial(object, context);
+        else if (type.equals(GenericRefType.class.getSimpleName()))         return GenericRefType.fromSerial(object, context);
+        else if (type.equals(SuperWildcardType.class.getSimpleName()))      return SuperWildcardType.fromSerial(object, context);
+        else if (type.equals(RefType.class.getSimpleName()))                return RefType.fromSerial(object, context);
+        else if (type.equals(Void.class.getSimpleName()))                   return Void.fromSerial(object, context);
+        else if (type.equals(TypePlaceholder.class.getSimpleName()))        return TypePlaceholder.fromSerial(object, context);
+        else throw new RuntimeException("Could not unserialize class of unhandled type " + type);
+    }
 }

src/main/java/de/dhbwstuttgart/syntaxtree/type/SuperWildcardType.java

@@ -1,9 +1,13 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
 
+import de.dhbwstuttgart.parser.NullToken;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
-import de.dhbwstuttgart.syntaxtree.GenericTypeVar;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
 import java.util.Objects;
@@ -16,7 +20,7 @@ import java.util.Objects;
  * 
  */
 
-public class SuperWildcardType extends WildcardType{
+public class SuperWildcardType extends WildcardType implements ISerializableData {
 
 	/**
 	* Author: Arne Lüdtke<br/>
@@ -80,4 +84,22 @@ public class SuperWildcardType extends WildcardType{
 		SuperWildcardType that = (SuperWildcardType) o;
 		return that.innerType.equals(this.innerType);
 	}
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("innerType", this.innerType.toSerial(keyStorage));
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static SuperWildcardType fromSerial(SerialMap data, UnifyContext context) {
+		return new SuperWildcardType(
+			RefTypeOrTPHOrWildcardOrGeneric.fromSerial(data.getMap("innerType"), context),
+			new NullToken()
+		);
+	}
 }

src/main/java/de/dhbwstuttgart/syntaxtree/type/TypePlaceholder.java

@@ -1,9 +1,12 @@
 package de.dhbwstuttgart.syntaxtree.type;
-import java.util.Hashtable;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.syntaxtree.ASTVisitor;
-import de.dhbwstuttgart.syntaxtree.SyntaxTreeNode;
 import de.dhbwstuttgart.syntaxtree.factory.NameGenerator;
 import de.dhbwstuttgart.typeinference.result.ResultSetVisitor;
 import org.antlr.v4.runtime.Token;
@@ -16,7 +19,7 @@ import org.antlr.v4.runtime.Token;
  * @author J�rg B�uerle
  * @version $Date: 2013/06/19 12:45:37 $
  */
-public class TypePlaceholder extends RefTypeOrTPHOrWildcardOrGeneric
+public class TypePlaceholder extends RefTypeOrTPHOrWildcardOrGeneric implements ISerializableData
 {
 	private final String name;
 	
@@ -65,7 +68,12 @@ public class TypePlaceholder extends RefTypeOrTPHOrWildcardOrGeneric
     public static TypePlaceholder fresh(Token position){
 		return new TypePlaceholder(NameGenerator.makeNewName(), position, 0, true);
     }
-    
+
+  public static TypePlaceholder fresh(Token position, PlaceholderRegistry placeholderRegistry){
+    String newName = placeholderRegistry.generateFreshPlaceholderName();
+    return new TypePlaceholder(newName, position, 0, true);
+  }
+
     public static TypePlaceholder fresh(Token position, int variance, boolean wildcardable){
 		return new TypePlaceholder(NameGenerator.makeNewName(), position, variance, wildcardable);
     }
@@ -139,4 +147,26 @@ public class TypePlaceholder extends RefTypeOrTPHOrWildcardOrGeneric
 	public Boolean getWildcardtable() {
 		return wildcardable;
 	}
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("name", this.name);
+    serialized.put("variance", this.variance);
+    serialized.put("wildcardable", this.wildcardable);
+
+    // create the wrapper and put this as the object
+    var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+    serializedWrapper.put("object", serialized);
+    return serializedWrapper;
+  }
+
+  public static TypePlaceholder fromSerial(SerialMap data, UnifyContext context) {
+    return new TypePlaceholder(
+      data.getValue("name").getOf(String.class),
+      new NullToken(),
+      data.getValue("variance").getOf(Integer.class),
+      data.getValue("wildcardable").getOf(Boolean.class)
+    );
+  }
 }

src/main/java/de/dhbwstuttgart/syntaxtree/type/Void.java

@@ -1,14 +1,32 @@
 package de.dhbwstuttgart.syntaxtree.type;
 
+import de.dhbwstuttgart.parser.NullToken;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import org.antlr.v4.runtime.Token;
 
 import de.dhbwstuttgart.parser.scope.JavaClassName;
 
 
-public class Void extends RefType
+public class Void extends RefType implements ISerializableData
 {
     public Void(Token offset) {
         super(JavaClassName.Void, offset);
     }
+
+    @Override
+    public ISerialNode toSerial(KeyStorage keyStorage) {
+        // create the wrapper and put this as the object
+        var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+        serializedWrapper.put("object", new SerialMap());
+        return serializedWrapper;
+    }
+
+    public static Void fromSerial(SerialMap data, UnifyContext context) {
+        return new Void(new NullToken());
+    }
 }
 

src/main/java/de/dhbwstuttgart/target/Target.java

@@ -0,0 +1,8 @@
+package de.dhbwstuttgart.target;
+
+import de.dhbwstuttgart.util.Logger;
+
+public class Target {
+  public static Logger logger = new Logger("Target");
+
+}

src/main/java/de/dhbwstuttgart/target/generate/ASTToTargetAST.java

@@ -12,6 +12,7 @@ import de.dhbwstuttgart.syntaxtree.Record;
 import de.dhbwstuttgart.syntaxtree.factory.ASTFactory;
 import de.dhbwstuttgart.syntaxtree.statement.*;
 import de.dhbwstuttgart.syntaxtree.type.*;
+import de.dhbwstuttgart.target.Target;
 import de.dhbwstuttgart.target.tree.*;
 import de.dhbwstuttgart.target.tree.expression.*;
 import de.dhbwstuttgart.target.tree.type.*;
@@ -337,10 +338,10 @@ public class ASTToTargetAST {
 
         var result = r0.stream().map(l -> l.stream().toList()).toList();
 
-        System.out.println("============== OUTPUT ==============");
+        Target.logger.info("============== OUTPUT ==============");
         for (var l : result) {
-            for (var m : l) System.out.println(m.name() + " " + m.getSignature());
-            System.out.println();
+            for (var m : l) Target.logger.info(m.name() + " " + m.getSignature());
+            Target.logger.info("");
         }
         return result;
     }

src/main/java/de/dhbwstuttgart/target/generate/GenerateGenerics.java

@@ -1,10 +1,12 @@
 package de.dhbwstuttgart.target.generate;
 
+import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.syntaxtree.*;
 import de.dhbwstuttgart.syntaxtree.statement.*;
 import de.dhbwstuttgart.syntaxtree.type.*;
 import de.dhbwstuttgart.syntaxtree.type.Void;
+import de.dhbwstuttgart.target.Target;
 import de.dhbwstuttgart.target.tree.type.TargetGenericType;
 import de.dhbwstuttgart.target.tree.type.TargetType;
 import de.dhbwstuttgart.typeinference.result.PairTPHEqualTPH;
@@ -138,17 +140,17 @@ public abstract class GenerateGenerics {
         this.astToTargetAST = astToTargetAST;
         for (var constraint : constraints.results) {
             if (constraint instanceof PairTPHsmallerTPH p) {
-                System.out.println(p.left + " " + p.left.getVariance());
+                Target.logger.info(p.left + " " + p.left.getVariance());
                 simplifiedConstraints.add(new PairLT(new TPH(p.left), new TPH(p.right)));
             } else if (constraint instanceof PairTPHEqualTPH p) {
                 equality.put(p.getLeft(), p.getRight());
             } else if (constraint instanceof PairTPHequalRefTypeOrWildcardType p) {
-                System.out.println(p.left + " = " + p.right);
+                Target.logger.info(p.left + " = " + p.right);
                 concreteTypes.put(new TPH(p.left), p.right);
             }
         }
 
-        System.out.println("Simplified constraints: " + simplifiedConstraints);
+        Target.logger.info("Simplified constraints: " + simplifiedConstraints);
     }
 
     /*public record GenericsState(Map<TPH, RefTypeOrTPHOrWildcardOrGeneric> concreteTypes, Map<TypePlaceholder, TypePlaceholder> equality) {}
@@ -248,7 +250,7 @@ public abstract class GenerateGenerics {
                 equality.put(entry.getKey(), to);
             }
         }
-        System.out.println(from + " -> " + to + " " + from.getVariance());
+        Target.logger.info(from + " -> " + to + " " + from.getVariance());
         //from.setVariance(to.getVariance());
         equality.put(from, to);
         referenced.remove(new TPH(from));
@@ -317,7 +319,7 @@ public abstract class GenerateGenerics {
                     Set<TPH> T2s = new HashSet<>();
                     findTphs(superType, T2s);
 
-                    System.out.println("T1s: " + T1s + " T2s: " + T2s);
+                    Target.logger.info("T1s: " + T1s + " T2s: " + T2s);
                     //Ende
 
                     superType = methodCall.receiverType;
@@ -332,7 +334,7 @@ public abstract class GenerateGenerics {
                             var optMethod = astToTargetAST.findMethod(owner, methodCall.name, methodCall.signatureArguments().stream().map(astToTargetAST::convert).toList());
                             if (optMethod.isEmpty()) return;
                             var method2 = optMethod.get();
-                            System.out.println("In: " + method.getName() + " Method: " + method2.getName());
+                            Target.logger.info("In: " + method.getName() + " Method: " + method2.getName());
                             var generics = family(owner, method2);
 
                             // transitive and
@@ -365,7 +367,7 @@ public abstract class GenerateGenerics {
                                                     if (!T1s.contains(R1) || !T2s.contains(R2)) continue;
 
                                                     var newPair = new PairLT(R1, R2);
-                                                    System.out.println("New pair: " + newPair);
+                                                    Target.logger.info("New pair: " + newPair);
                                                     newPairs.add(newPair);
 
                                                     if (!containsRelation(result, newPair))
@@ -567,7 +569,7 @@ public abstract class GenerateGenerics {
     Set<Pair> generics(ClassOrInterface owner, Method method) {
         if (computedGenericsOfMethods.containsKey(method)) {
             var cached = computedGenericsOfMethods.get(method);
-            System.out.println("Cached " + method.getName() + ": " + cached);
+            Target.logger.info("Cached " + method.getName() + ": " + cached);
             return cached;
         }
 
@@ -596,7 +598,7 @@ public abstract class GenerateGenerics {
 
         normalize(result, classGenerics, usedTphs);
 
-        System.out.println(this.getClass().getSimpleName() + " " + method.name + ": " + result);
+        Target.logger.info(this.getClass().getSimpleName() + " " + method.name + ": " + result);
         return result;
     }
 
@@ -675,7 +677,7 @@ public abstract class GenerateGenerics {
 
         normalize(javaResult, null, referencedByClass);
 
-        System.out.println(this.getClass().getSimpleName() + " Class " + classOrInterface.getClassName().getClassName() + ": " + javaResult);
+        Target.logger.info(this.getClass().getSimpleName() + " Class " + classOrInterface.getClassName().getClassName() + ": " + javaResult);
         return javaResult;
     }
 
@@ -726,7 +728,7 @@ public abstract class GenerateGenerics {
                     if (!added) break;
                 }
 
-                System.out.println(chain + " " + chain.stream().map(e -> e.resolve().getVariance()).toList());
+                Target.logger.info(chain + " " + chain.stream().map(e -> e.resolve().getVariance()).toList());
                 var variance = chain.get(0).resolve().getVariance();
                 if (variance != 1) continue;
                 var index = 0;
@@ -764,7 +766,7 @@ public abstract class GenerateGenerics {
         }
 
         for (var pair : elementsToAddToEquality) {
-            System.out.println(pair);
+            Target.logger.info(pair);
             addToEquality(pair.left, pair.right, referenced);
         }
     }
@@ -917,11 +919,11 @@ public abstract class GenerateGenerics {
                     }
                 }
                 if (infima.size() > 1) {
-                    System.out.println(infima);
+                    Target.logger.info(infima);
                     for (var pair : infima) {
                         var returnTypes = findTypeVariables(method.getReturnType());
                         var chain = findConnectionToReturnType(returnTypes, input, new HashSet<>(), pair.left);
-                        System.out.println("Find: " + pair.left + " " + chain);
+                        Target.logger.info("Find: " + pair.left + " " + chain);
                         chain.remove(pair.left);
                         if (chain.size() > 0) {
                             for (var tph : chain)
@@ -959,8 +961,8 @@ public abstract class GenerateGenerics {
                         }
                     }
                     newTph.setVariance(variance);
-                    System.out.println(infima + " " + infima.stream().map(i -> i.right.resolve().getVariance()).toList());
-                    System.out.println("Infima new TPH " + newTph + " variance " + variance);
+                    Target.logger.info(infima + " " + infima.stream().map(i -> i.right.resolve().getVariance()).toList());
+                    Target.logger.info("Infima new TPH " + newTph + " variance " + variance);
 
                     //referenced.add(newTph);
                     addToPairs(input, new PairLT(left, new TPH(newTph)));

src/main/java/de/dhbwstuttgart/target/generate/StatementToTargetExpression.java

@@ -8,6 +8,7 @@ import de.dhbwstuttgart.parser.scope.JavaClassName;
 import de.dhbwstuttgart.syntaxtree.*;
 import de.dhbwstuttgart.syntaxtree.statement.*;
 import de.dhbwstuttgart.syntaxtree.type.*;
+import de.dhbwstuttgart.target.Target;
 import de.dhbwstuttgart.target.tree.MethodParameter;
 import de.dhbwstuttgart.target.tree.TargetMethod;
 import de.dhbwstuttgart.target.tree.expression.*;
@@ -120,7 +121,7 @@ public class StatementToTargetExpression implements ASTVisitor {
 
     @Override
     public void visit(BoolExpression bool) {
-        System.out.println("BoolExpression");
+        Target.logger.info("BoolExpression");
     }
 
     @Override
@@ -234,7 +235,7 @@ public class StatementToTargetExpression implements ASTVisitor {
             isInterface = receiverClass.isInterface();
         }
 
-        System.out.println(argList);
+        Target.logger.info(argList);
         result = new TargetMethodCall(converter.convert(methodCall.getType()), returnType, argList, converter.convert(methodCall.receiver), methodCall.getArgumentList().getArguments().stream().map(converter::convert).toList(), receiverType, methodCall.name, isStatic, isInterface, isPrivate);
     }
 

src/main/java/de/dhbwstuttgart/typeinference/assumptions/FunNClass.java

@@ -9,13 +9,8 @@ import de.dhbwstuttgart.syntaxtree.Method;
 import de.dhbwstuttgart.syntaxtree.factory.ASTFactory;
 import de.dhbwstuttgart.syntaxtree.factory.NameGenerator;
 import de.dhbwstuttgart.syntaxtree.type.GenericRefType;
-import de.dhbwstuttgart.syntaxtree.type.RefType;
-import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
-import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
 
-import org.antlr.v4.runtime.Token;
 
-import javax.swing.text.html.Option;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;

src/main/java/de/dhbwstuttgart/typeinference/assumptions/MethodAssumption.java

@@ -19,11 +19,11 @@ public class MethodAssumption extends Assumption{
     private ClassOrInterface receiver;
     private RefTypeOrTPHOrWildcardOrGeneric retType;
     List<? extends RefTypeOrTPHOrWildcardOrGeneric> params;
-    private final Boolean isInherited;
-    private final Boolean isOverridden;
+    private final boolean isInherited;
+    private final boolean isOverridden;
 
     public MethodAssumption(ClassOrInterface receiver, RefTypeOrTPHOrWildcardOrGeneric retType,
-                            List<? extends RefTypeOrTPHOrWildcardOrGeneric> params, TypeScope scope, Boolean isInherited, Boolean isOverridden){
+                            List<? extends RefTypeOrTPHOrWildcardOrGeneric> params, TypeScope scope, boolean isInherited, boolean isOverridden){
         super(scope);
         this.receiver = receiver;
         this.retType = retType;
@@ -73,11 +73,11 @@ public class MethodAssumption extends Assumption{
         return TYPEStmt.getReceiverType(receiver, resolver);
     }
     
-    public Boolean isInherited() {
+    public boolean isInherited() {
     	return isInherited;
     }
     
-    public Boolean isOverridden() {
+    public boolean isOverridden() {
     	return isOverridden;
     }
 }

src/main/java/de/dhbwstuttgart/typeinference/constraints/Constraint.java

@@ -1,77 +1,171 @@
 package de.dhbwstuttgart.typeinference.constraints;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.ISerialNode;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialUUID;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
 
-import java.util.Collection;
+import java.util.ArrayList;
 import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
 import java.util.Set;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import javax.annotation.Nullable;
 
-public class Constraint<A> extends HashSet<A> {
-	private static final long serialVersionUID = 1L;
-	private Boolean isInherited = false;//wird beides nur für die Method-Constraints benoetigt
-	private Boolean isImplemented = false;
-	
-	/*
-	 * wird verwendet um bei der Codegenerierung die richtige Methoden - Signatur
-	 * auszuwaehlen 
-	 */
-	/*private*/ Set<A> methodSignatureConstraint = new HashSet<>();
-	
-	private Constraint<A> extendConstraint = null;
-	
-	public Constraint() {
-		super();
-	}
-	
-	public Constraint(Boolean isInherited, Boolean isImplemented) {
-		this.isInherited = isInherited;
-		this.isImplemented = isImplemented;
-	}
-	
-	public Constraint(Boolean isInherited, Boolean isImplemented, Constraint<A> extendConstraint, Set<A> methodSignatureConstraint) {
-		this.isInherited = isInherited;
-		this.isImplemented = isImplemented;
-		this.extendConstraint = extendConstraint;
-		this.methodSignatureConstraint = methodSignatureConstraint;
-	}
-	
-	public void setIsInherited(Boolean isInherited) {
-		this.isInherited = isInherited;
-	}
-	
-	public Boolean isInherited() {
-		return isInherited;
-	}
-	
-	public Boolean isImplemented() {
-		return isImplemented;
-	}
-	
-	public Constraint<A> getExtendConstraint() {
-		return extendConstraint;
-	}
-	
-	public void setExtendConstraint(Constraint<A> c) {
-		extendConstraint = c;
-	}
-	
-	public Set<A> getmethodSignatureConstraint() {
-		return methodSignatureConstraint;
-	}
-	
-	public void setmethodSignatureConstraint(Set<A> c) {
-		methodSignatureConstraint = c;
-	}
+public class Constraint<A extends IConstraintElement> extends HashSet<A> implements ISerializableData {
+  private static final long serialVersionUID = 1L;
+  private boolean isInherited = false;//wird beides nur für die Method-Constraints benoetigt
+  private boolean isImplemented = false;
+
+  /*
+   * wird verwendet um bei der Codegenerierung die richtige Methoden - Signatur
+   * auszuwaehlen
+   */
+  /*private*/ Set<A> methodSignatureConstraint = new HashSet<>();
+
+  private Constraint<A> extendConstraint = null;
+
+  public Constraint() {
+    super();
+  }
+
+  public Constraint(int initialCapacity) {
+    super(initialCapacity);
+  }
+
+  public Constraint(boolean isInherited, boolean isImplemented) {
+    this.isInherited = isInherited;
+    this.isImplemented = isImplemented;
+  }
+
+  public Constraint(boolean isInherited, boolean isImplemented, Constraint<A> extendConstraint, Set<A> methodSignatureConstraint) {
+    this.isInherited = isInherited;
+    this.isImplemented = isImplemented;
+    this.extendConstraint = extendConstraint;
+    this.methodSignatureConstraint = methodSignatureConstraint;
+  }
+
+  public void setIsInherited(boolean isInherited) {
+    this.isInherited = isInherited;
+  }
+
+  public boolean isInherited() {
+    return isInherited;
+  }
+
+  public boolean isImplemented() {
+    return isImplemented;
+  }
+
+  public Constraint<A> getExtendConstraint() {
+    return extendConstraint;
+  }
+
+  public void setExtendConstraint(Constraint<A> c) {
+    extendConstraint = c;
+  }
+
+  public Set<A> getmethodSignatureConstraint() {
+    return methodSignatureConstraint;
+  }
+
+  public void setmethodSignatureConstraint(Set<A> c) {
+    methodSignatureConstraint = c;
+  }
+
+  public <B extends IConstraintElement> Constraint<B> createdMapped(Function<A,B> mapper) {
+    Constraint<B> result = new Constraint<>(this.size());
+    for (A element : this) {
+      result.add(mapper.apply(element));
+    }
+    return result;
+  }
+
+  public String toString() {
+    return super.toString() + "\nisInherited = " + isInherited
+      + " isOveridden = " + isImplemented
+      + " msc[" + methodSignatureConstraint.size() + "] = " + methodSignatureConstraint
+      //" + extendsContraint: "  + (extendConstraint != null ? extendConstraint.toStringBase() : "null" )
+      + "\n";
+  }
+
+  public String toStringBase() {
+    return super.toString();
+  }
+
+  private String serialUUID = null;
+
+  @Override
+  public SerialUUID toSerial(KeyStorage keyStorage) {
+    final String uuid = serialUUID == null ? keyStorage.getIdentifier() : serialUUID;
+    if (serialUUID == null) serialUUID = uuid;
+
+    if (!keyStorage.isAlreadySerialized(uuid)) {
+      SerialMap serialized = new SerialMap();
+      keyStorage.putSerialized(uuid, serialized);
+      serialized.put("isInherited", isInherited);
+      serialized.put("isImplemented", isImplemented);
+      serialized.put("extendedConstraint", extendConstraint == null ? null :
+        extendConstraint.toSerial(keyStorage));
+      Function<A, ISerialNode> pairMapper = pair -> {
+        if (pair instanceof Pair simplePair) return simplePair.toSerial(keyStorage);
+        if (pair instanceof UnifyPair unifyPair) return unifyPair.toSerial(keyStorage);
+        throw new RuntimeException("No serialization is supported for type " + pair.getClass().getName());
+      };
+      serialized.put("methodSignatureConstraint", methodSignatureConstraint == null ? null :
+        SerialList.fromMapped(methodSignatureConstraint, pairMapper));
+      serialized.put("setElements", SerialList.fromMapped(this, pairMapper));
+    }
+
+    // return only the unique key
+    return new SerialUUID(uuid);
+  }
+
+  public static <T extends IConstraintElement> Constraint<T> fromSerial(SerialUUID serialUUID, UnifyContext context, Class<T> target, KeyStorage keyStorage) {
+    String uuid = serialUUID.uuid;
+
+    if (!keyStorage.isAlreadyUnserialized(uuid)) {
+      Constraint<T> constraint = new Constraint<>();
+      // immediately add the object to the context to prevent infinite recursion
+      keyStorage.putUnserialized(uuid, constraint);
+
+      // retrieve the serialized data und start unserializing it
+      SerialMap data = keyStorage.getSerialized(uuid);
+      constraint.isInherited = data.getValue("isInherited").getOf(Boolean.class);
+      constraint.isImplemented = data.getValue("isImplemented").getOf(Boolean.class);
+      constraint.extendConstraint = Optional.ofNullable(data.getUUIDOrNull("extendedConstraint"))
+        .map(v -> Constraint.fromSerial(v, context, target, keyStorage))
+        .orElse(null);
+
+      // to convert the maps back to elements, we sadly have to do some assumptions about the generic types...
+      Function<ISerialNode, T> pairUnmapper = pairData -> {
+        if (target == Pair.class && pairData instanceof SerialMap pairMap) {
+          return (T) Pair.fromSerial(pairMap, context);
+        }
+        if (target == UnifyPair.class && pairData instanceof SerialUUID pairUUID) {
+          return (T) UnifyPair.fromSerial(pairUUID, context, keyStorage);
+        }
+        throw new RuntimeException("No serialization is supported for target type " + target.getName());
+      };
+
+      constraint.methodSignatureConstraint =
+        Optional.ofNullable(data.getListOrNull("methodSignatureConstraint"))
+          .map(l -> l.stream().map(pairUnmapper).collect(Collectors.toSet()))
+          .orElse(null);
+      constraint.addAll(
+        data.getList("setElements")
+          .stream().map(pairUnmapper).toList());
+    }
+
+    return keyStorage.getUnserialized(uuid, Constraint.class);
+  }
 
-	public String toString() {
-		return super.toString() + "\nisInherited = " + isInherited + " isOveridden = " + isImplemented
-				+ methodSignatureConstraint
-				//" + extendsContraint: "  + (extendConstraint != null ? extendConstraint.toStringBase() : "null" ) 
-				+ "\n" ;
-	}
-	
-	public String toStringBase() {
-		return super.toString();
-	}
-	
 }

src/main/java/de/dhbwstuttgart/typeinference/constraints/ConstraintSet.java

@@ -1,63 +1,80 @@
 package de.dhbwstuttgart.typeinference.constraints;
 
 
-import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.typeinference.unify.GuavaSetOperations;
-import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
+import de.dhbwstuttgart.typeinference.unify.model.FiniteClosure;
 import java.util.*;
 import java.util.function.BinaryOperator;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
-public class ConstraintSet<A> {
-    Constraint<A> undConstraints = new Constraint<>();
-    List<Set<Constraint<A>>> oderConstraints = new ArrayList<>();
+public class ConstraintSet<A extends IConstraintElement> implements ISerializableData {
+  Constraint<A> undConstraints = new Constraint<>();
+  List<Set<Constraint<A>>> oderConstraints = new ArrayList<>();
 
-    public void addUndConstraint(A p){
-        undConstraints.add(p);
-    }
+  public void addUndConstraint(A p) {
+    undConstraints.add(p);
+  }
 
-    public void addOderConstraint(Set<Constraint<A>> methodConstraints) {
-        oderConstraints.add(methodConstraints);
-    }
+  public void addOderConstraint(Set<Constraint<A>> methodConstraints) {
+    oderConstraints.add(methodConstraints);
+  }
 
-    public void addAllUndConstraint(Constraint<A> allUndConstraints){
-        undConstraints.addAll(allUndConstraints);
-    }
-    
-    public void addAllOderConstraint(List<Set<Constraint<A>>> allOderConstraints){
-        this.oderConstraints.addAll(allOderConstraints);
-    }
-    
-    public void addAll(ConstraintSet constraints) {
-        this.addAllUndConstraint(constraints.undConstraints);
-        this.addAllOderConstraint(constraints.oderConstraints);
-    }
+  public void addAllUndConstraint(Constraint<A> allUndConstraints) {
+    undConstraints.addAll(allUndConstraints);
+  }
 
-    @Override
-    public String toString(){
-    	BinaryOperator<String> b = (x,y) -> x+y;
-        return "\nUND:" + this.undConstraints.toString() + "\n" + 
-    		   "ODER:" + this.oderConstraints.stream().reduce("", (x,y) -> x.toString()+ "\n"  +y, b);
-        		//cartesianProduct().toString();
-    }
+  public void addAllOderConstraint(List<Set<Constraint<A>>> allOderConstraints) {
+    this.oderConstraints.addAll(allOderConstraints);
+  }
 
-    public Set<List<Constraint<A>>> cartesianProduct(){
-        Set<Constraint<A>> toAdd = new HashSet<>();
-        toAdd.add(undConstraints);
-        List<Set<Constraint<A>>> allConstraints = new ArrayList<>();
-        allConstraints.add(toAdd);
-        allConstraints.addAll(oderConstraints);
-        return new GuavaSetOperations().cartesianProduct(allConstraints);
-    }
+  public void addAll(ConstraintSet constraints) {
+    this.addAllUndConstraint(constraints.undConstraints);
+    this.addAllOderConstraint(constraints.oderConstraints);
+  }
 
-    public <B> ConstraintSet<B> map(Function<? super A, ? extends B> o) {
-    	Hashtable<Constraint<A>,Constraint<B>> CSA2CSB = new Hashtable<>();
-        ConstraintSet<B> ret = new ConstraintSet<>();
-        ret.undConstraints = undConstraints.stream().map(o).collect(Collectors.toCollection(Constraint<B>::new));
-        List<Set<Constraint<B>>> newOder = new ArrayList<>();
+  @Override
+  public String toString() {
+    BinaryOperator<String> b = (x, y) -> x + y;
+    return "\nUND:\n" + this.undConstraints.toString() +
+      "ODER:" + this.oderConstraints.stream().reduce("", (x, y) -> x + "\n\t" + y, b) +
+      "\n";
+    //cartesianProduct().toString();
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (!(obj instanceof ConstraintSet<?> other)) return false;
+    return Objects.equals(undConstraints, other.undConstraints)
+      && Objects.equals(oderConstraints, other.oderConstraints);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(undConstraints, oderConstraints);
+  }
+
+  public Set<List<Constraint<A>>> cartesianProduct() {
+    Set<Constraint<A>> toAdd = new HashSet<>();
+    toAdd.add(undConstraints);
+    List<Set<Constraint<A>>> allConstraints = new ArrayList<>();
+    allConstraints.add(toAdd);
+    allConstraints.addAll(oderConstraints);
+    return new GuavaSetOperations().cartesianProduct(allConstraints);
+  }
+
+  public <B extends IConstraintElement> ConstraintSet<B> map(Function<? super A, ? extends B> o) {
+    Hashtable<Constraint<A>, Constraint<B>> CSA2CSB = new Hashtable<>();
+    ConstraintSet<B> ret = new ConstraintSet<>();
+    ret.undConstraints = undConstraints.stream().map(o).collect(Collectors.toCollection(Constraint<B>::new));
+    List<Set<Constraint<B>>> newOder = new ArrayList<>();
         /*
         for(Set<Constraint<A>> oderConstraint : oderConstraints){
         	oderConstraint.forEach(as -> {
@@ -68,25 +85,25 @@ public class ConstraintSet<A> {
             	CSA2CSB.put(as, newConst);} );
         }
         */
-        
-        for(Set<Constraint<A>> oderConstraint : oderConstraints){
-            newOder.add(
-                    oderConstraint.stream().map((Constraint<A> as) -> {
-                    	
-                    	Constraint<B> newConst = as.stream()
-                    			.map(o)
-                    			.collect(Collectors.toCollection((
-                    					() -> new Constraint<B> (as.isInherited(),
-                    											 as.isImplemented(),
-                    											 (as.getExtendConstraint() != null)
-                    											     ? as.getExtendConstraint().stream().map(o).collect(Collectors.toCollection(Constraint::new))
-                    											     : null,
-                    							                 as.getmethodSignatureConstraint().stream().map(o).collect(Collectors.toCollection(HashSet::new)))) 
-                    			));                    							
-                    	
-                    	//CSA2CSB.put(as, newConst);
-                    	
-                    	return newConst;
+
+    for (Set<Constraint<A>> oderConstraint : oderConstraints) {
+      newOder.add(
+        oderConstraint.stream().map((Constraint<A> as) -> {
+
+          Constraint<B> newConst = as.stream()
+            .map(o)
+            .collect(Collectors.toCollection((
+              () -> new Constraint<B>(as.isInherited(),
+                as.isImplemented(),
+                (as.getExtendConstraint() != null)
+                  ? as.getExtendConstraint().stream().map(o).collect(Collectors.toCollection(Constraint::new))
+                  : null,
+                as.getmethodSignatureConstraint().stream().map(o).collect(Collectors.toCollection(HashSet::new))))
+            ));
+
+          //CSA2CSB.put(as, newConst);
+
+          return newConst;
                     	
                     	/*
                     	Constraint<B> bs = CSA2CSB.get(as);
@@ -95,36 +112,60 @@ public class ConstraintSet<A> {
                     	}
                     	return bs;
                     	*/
-                    }).collect(Collectors.toSet())
-            );
-        }
-        
-        ret.oderConstraints = newOder;
-        return ret;
+        }).collect(Collectors.toSet())
+      );
     }
-    
-    public void forEach (Consumer<? super A> c) {
-        undConstraints.stream().forEach(c);
-        for(Set<Constraint<A>> oderConstraint : oderConstraints){
-            oderConstraint.parallelStream().forEach((Constraint<A> as) ->
-                            as.stream().forEach(c));
-        }
+
+    ret.oderConstraints = newOder;
+    return ret;
+  }
+
+  public void forEach(Consumer<? super A> c) {
+    undConstraints.stream().forEach(c);
+    for (Set<Constraint<A>> oderConstraint : oderConstraints) {
+      oderConstraint.parallelStream().forEach((Constraint<A> as) ->
+        as.stream().forEach(c));
     }
-    
-    public Set<A> getAll () {
-    	Set<A> ret = new HashSet<>();
-        ret.addAll(undConstraints);
-        for(Set<Constraint<A>> oderConstraint : oderConstraints){
-            oderConstraint.parallelStream().forEach((Constraint<A> as) -> ret.addAll(as));
-        }
-        return ret;
-    }
-    
-    public List<Set<Constraint<A>>> getOderConstraints() {
-    	return oderConstraints;
-    }
-    
-    public Set<A> getUndConstraints() {
-    	return undConstraints;
+  }
+
+  public Set<A> getAll() {
+    Set<A> ret = new HashSet<>(undConstraints);
+    for (Set<Constraint<A>> oderConstraint : oderConstraints) {
+      oderConstraint.parallelStream().forEach(ret::addAll);
     }
+    return ret;
+  }
+
+  public List<Set<Constraint<A>>> getOderConstraints() {
+    return oderConstraints;
+  }
+
+  public Set<A> getUndConstraints() {
+    return undConstraints;
+  }
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("undConstraints", undConstraints.toSerial(keyStorage));
+    serialized.put("oderConstraints", SerialList.fromMapped(oderConstraints, oderConstraintSet ->
+      SerialList.fromMapped(oderConstraintSet, oderConstraint ->
+        oderConstraint.toSerial(keyStorage))
+    ));
+    return serialized;
+  }
+
+  public static <T extends IConstraintElement> ConstraintSet<T> fromSerial(SerialMap data, UnifyContext context, Class<T> target, KeyStorage keyStorage) {
+    ConstraintSet<T> constraintSet = new ConstraintSet<>();
+
+    constraintSet.undConstraints = Constraint.fromSerial(data.getUUID("undConstraints"), context, target, keyStorage);
+    constraintSet.oderConstraints = data.getList("oderConstraints").assertListOfLists().stream()
+      .map(oderConstraintSetData -> oderConstraintSetData.assertListOfUUIDs().stream()
+        .map(oderConstraintData -> Constraint.fromSerial(oderConstraintData, context, target, keyStorage))
+        .collect(Collectors.toSet())
+      ).toList();
+
+    return constraintSet;
+  }
+
 }

src/main/java/de/dhbwstuttgart/typeinference/constraints/IConstraintElement.java

@@ -0,0 +1,4 @@
+package de.dhbwstuttgart.typeinference.constraints;
+
+public interface IConstraintElement {
+}

src/main/java/de/dhbwstuttgart/typeinference/constraints/Pair.java

@@ -1,72 +1,70 @@
 package de.dhbwstuttgart.typeinference.constraints;
+
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.io.Serializable;
 import java.util.HashMap;
 import java.util.Map;
 
-import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.parser.SourceLoc;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
 import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
 import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
-import org.antlr.v4.runtime.Token;
 
 
-public class Pair implements Serializable
-{
-    public final RefTypeOrTPHOrWildcardOrGeneric TA1;
-    public final RefTypeOrTPHOrWildcardOrGeneric TA2;
+public class Pair implements Serializable, IConstraintElement, ISerializableData {
+  public final RefTypeOrTPHOrWildcardOrGeneric TA1;
+  public final RefTypeOrTPHOrWildcardOrGeneric TA2;
 
-    private SourceLoc location;
+  private SourceLoc location;
 
-    private PairOperator eOperator = PairOperator.SMALLER;
-    private Boolean noUnification = false;
-    
+  private PairOperator eOperator = PairOperator.SMALLER;
+  private boolean noUnification = false;
 
-    private Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2 )
-    {
-        this.TA1 = TA1;
-        this.TA2 = TA2;
-        if(TA1 == null || TA2 == null)
-            throw new NullPointerException();
-        eOperator = PairOperator.SMALLER;
-    }
 
-    public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp)
-    {
-        // Konstruktor
-        this(TA1,TA2);
-        this.eOperator = eOp;
-    }
+  private Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2) {
+    this.TA1 = TA1;
+    this.TA2 = TA2;
+    if (TA1 == null || TA2 == null)
+      throw new NullPointerException();
+    eOperator = PairOperator.SMALLER;
+  }
 
-    public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator e0p, SourceLoc location) {
-        this(TA1, TA2, e0p);
-        this.location = location;
-    }
-    
-    public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp, Boolean noUnification)
-    {
-        // Konstruktor
-        this(TA1,TA2);
-        this.eOperator = eOp;
-        this.noUnification = noUnification;
-    }
+  public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp) {
+    // Konstruktor
+    this(TA1, TA2);
+    this.eOperator = eOp;
+  }
 
-    public SourceLoc getLocation() {
-        return this.location;
-    }
-    
-    public String toString()
-    {
-        // otth: Gibt ein Paar als String aus --> zum Debuggen und Vergleichen
-        String strElement1 = "NULL";
-        String strElement2 = "NULL";
-        String Operator = "<.";
-        
-        if( TA1 != null )
-             strElement1 = TA1.toString();
-    
-        if( TA2 != null )
-           strElement2 = TA2.toString();
+  public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator e0p, SourceLoc location) {
+    this(TA1, TA2, e0p);
+    this.location = location;
+  }
+
+  public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp, boolean noUnification) {
+    // Konstruktor
+    this(TA1, TA2);
+    this.eOperator = eOp;
+    this.noUnification = noUnification;
+  }
+
+  public SourceLoc getLocation() {
+    return this.location;
+  }
+
+  public String toString() {
+    // otth: Gibt ein Paar als String aus --> zum Debuggen und Vergleichen
+    String strElement1 = "NULL";
+    String strElement2 = "NULL";
+    String Operator = "<.";
+
+    if (TA1 != null)
+      strElement1 = TA1.toString();
+
+    if (TA2 != null)
+      strElement2 = TA2.toString();
         
        /* PL ausskommentiert 2018-05-24
         if(OperatorEqual())
@@ -76,80 +74,104 @@ public class Pair implements Serializable
         if(OperatorSmallerExtends())
         	Operator = "<?";
         	*/
-        
-        return "\n(" + strElement1 + " " + eOperator.toString() + " " + strElement2 + ")";
-        
-       /*- Equals: " + bEqual*/
-    }
 
-    /**
-     * <br/>Author: J�rg B�uerle
-     * @param obj
-     * @return
-     */
-    public boolean equals(Object obj)
-    {
-        boolean ret = true;
-        ret &= (obj instanceof Pair);
-        if(!ret)return ret;
-        ret &= ((Pair)obj).TA1.equals(this.TA1);
-        ret &= ((Pair)obj).TA2.equals(this.TA2);
-        return ret;
-    }
+    return "\n(P: " + strElement1 + " " + eOperator.toString() + " " + strElement2 + ")";
 
-    /**
-	* Author: Arne Lüdtke<br/>
-	* Abfrage, ob Operator vom Typ Equal ist.
-	*/
-    public boolean OperatorEqual()
-    {
-    	return eOperator == PairOperator.EQUALSDOT;
-    }
-    
-    /**
-	* Author: Arne Lüdtke<br/>
-	* Abfrage, ob Operator vom Typ Smaller ist.
-	*/
-    public boolean OperatorSmaller()
-    {
-    	return eOperator == PairOperator.SMALLER;
-    }
-    
-    /**
-	* Author: Arne Lüdtke<br/>
-	* Abfrage, ob Operator vom Typ SmallerExtends ist.
-	*/
-    public boolean OperatorSmallerExtends()
-    {
-    	return eOperator == PairOperator.SMALLERDOTWC;
-    }
-    
-    /**
-	* Author: Arne Lüdtke<br/>
-	* Gibt den Operator zurück.
-	*/
-    public PairOperator GetOperator()
-    {
-    	return eOperator;
-    }
+    /*- Equals: " + bEqual*/
+  }
 
-    public boolean OperatorSmallerDot() {
-        return eOperator == PairOperator.SMALLERDOT;
-    }
-    
-    
-    static public Map<String, TypePlaceholder> generateTPHMap(ConstraintSet<Pair> constraints) {
-        HashMap<String, TypePlaceholder> ret = new HashMap<>();
-        constraints.map((Pair p) -> {
-            if (p.TA1 instanceof TypePlaceholder) {
-                ret.put(((TypePlaceholder) p.TA1).getName(), (TypePlaceholder) p.TA1);
-            }
-            if (p.TA2 instanceof TypePlaceholder) {
-                ret.put(((TypePlaceholder) p.TA2).getName(), (TypePlaceholder) p.TA2);
-            }
-            return null;
-        });
-        return ret;
-    }
+  /**
+   * <br/>Author: J�rg B�uerle
+   *
+   * @param obj
+   * @return
+   */
+  public boolean equals(Object obj) {
+    return (
+      (obj instanceof Pair pairObj) &&
+        pairObj.TA1.equals(this.TA1) &&
+        pairObj.TA2.equals(this.TA2)
+    );
+  }
+
+  /**
+   * Author: Arne Lüdtke<br/>
+   * Abfrage, ob Operator vom Typ Equal ist.
+   */
+  public boolean OperatorEqual() {
+    return eOperator == PairOperator.EQUALSDOT;
+  }
+
+  /**
+   * Author: Arne Lüdtke<br/>
+   * Abfrage, ob Operator vom Typ Smaller ist.
+   */
+  public boolean OperatorSmaller() {
+    return eOperator == PairOperator.SMALLER;
+  }
+
+  /**
+   * Author: Arne Lüdtke<br/>
+   * Abfrage, ob Operator vom Typ SmallerExtends ist.
+   */
+  public boolean OperatorSmallerExtends() {
+    return eOperator == PairOperator.SMALLERDOTWC;
+  }
+
+  /**
+   * Author: Arne Lüdtke<br/>
+   * Gibt den Operator zurück.
+   */
+  public PairOperator GetOperator() {
+    return eOperator;
+  }
+
+  public boolean OperatorSmallerDot() {
+    return eOperator == PairOperator.SMALLERDOT;
+  }
+
+
+  static public Map<String, TypePlaceholder> generateTPHMap(ConstraintSet<Pair> constraints) {
+    HashMap<String, TypePlaceholder> ret = new HashMap<>();
+    constraints.map((Pair p) -> {
+      if (p.TA1 instanceof TypePlaceholder) {
+        ret.put(((TypePlaceholder) p.TA1).getName(), (TypePlaceholder) p.TA1);
+      }
+      if (p.TA2 instanceof TypePlaceholder) {
+        ret.put(((TypePlaceholder) p.TA2).getName(), (TypePlaceholder) p.TA2);
+      }
+      return null;
+    });
+    return ret;
+  }
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    // because toString() will output TA1 and TA2 recursively, we can ignore potential infinite recursion here too
+    SerialMap serialized = new SerialMap();
+    serialized.put("ta1", this.TA1.toSerial(keyStorage));
+    serialized.put("ta2", this.TA2.toSerial(keyStorage));
+    serialized.put("op", this.eOperator.toString());
+    serialized.put("noUnification", this.noUnification ? 1 : 0);
+    serialized.put("location", this.location == null ? null : this.location.toSerial(keyStorage));
+    return serialized;
+  }
+
+  public static Pair fromSerial(SerialMap data, UnifyContext context) {
+    String op = data.getValue("op").getOf(String.class);
+    SerialMap ta1 = data.getMap("ta1");
+    SerialMap ta2 = data.getMap("ta2");
+    boolean noUnification = data.getValue("noUnification").getOf(Integer.class) == 1;
+    SerialMap location = data.getMapOrNull("location");
+
+    var pair = new Pair(
+      RefTypeOrTPHOrWildcardOrGeneric.fromSerial(ta1, context),
+      RefTypeOrTPHOrWildcardOrGeneric.fromSerial(ta2, context),
+      PairOperator.fromString(op),
+      noUnification
+    );
+    if (location != null) pair.location = SourceLoc.fromSerial(location);
+    return pair;
+  }
 }
 // ino.end

src/main/java/de/dhbwstuttgart/typeinference/result/PairNoResult.java

@@ -1,15 +1,19 @@
 package de.dhbwstuttgart.typeinference.result;
 
 import de.dhbwstuttgart.exceptions.NotImplementedException;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
-import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 /**
  * enthaelt alle Paare, die in einem Ergebnis nicht vorkommen koennen
  * sie sind noetig fuer origPairs in PairTPHsmallerTPH, da hier auch
  * Paare vorkommen koennen die keine Result sind (z.B. bei FunN$$)
  */
-public class PairNoResult extends ResultPair<RefTypeOrTPHOrWildcardOrGeneric, RefTypeOrTPHOrWildcardOrGeneric>{
+public class PairNoResult extends ResultPair<RefTypeOrTPHOrWildcardOrGeneric, RefTypeOrTPHOrWildcardOrGeneric>
+implements ISerializableData {
     //public final TypePlaceholder left;
     //public final TypePlaceholder right;
     
@@ -17,7 +21,7 @@ public class PairNoResult extends ResultPair<RefTypeOrTPHOrWildcardOrGeneric, Re
      * urspruengliches Paar aus diesem dieses Resultpair erzeugt wurde
      * wichtig fuer generated Generics
      */
-    ResultPair origPair;
+    ResultPair<?,?> origPair;
 
     public PairNoResult(RefTypeOrTPHOrWildcardOrGeneric left, RefTypeOrTPHOrWildcardOrGeneric right){
         super(left, right);
@@ -29,4 +33,24 @@ public class PairNoResult extends ResultPair<RefTypeOrTPHOrWildcardOrGeneric, Re
     	throw new NotImplementedException();
         //visitor.visit(this);
     }
+
+    @Override
+    public SerialMap toSerial(KeyStorage keyStorage) {
+        SerialMap serialized = new SerialMap();
+        serialized.put("left", this.getLeft().toSerial(keyStorage));
+        serialized.put("right", this.getRight().toSerial(keyStorage));
+        // create the wrapper and put this as the object
+        var serializedWrapper = super.toSerial(keyStorage);
+        serializedWrapper.put("object", serialized);
+        return serializedWrapper;
+    }
+
+    public static PairNoResult fromSerial2(SerialMap data, UnifyContext context) {
+        SerialMap left = data.getMap("left");
+        SerialMap right = data.getMap("right");
+        return new PairNoResult(
+          RefTypeOrTPHOrWildcardOrGeneric.fromSerial(left, context),
+          RefTypeOrTPHOrWildcardOrGeneric.fromSerial(right, context)
+        );
+    }
 }

src/main/java/de/dhbwstuttgart/typeinference/result/PairTPHEqualTPH.java

@@ -1,9 +1,13 @@
 package de.dhbwstuttgart.typeinference.result;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
 import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
-public class PairTPHEqualTPH extends ResultPair<TypePlaceholder, TypePlaceholder> {
+public class PairTPHEqualTPH extends ResultPair<TypePlaceholder, TypePlaceholder> implements ISerializableData {
     public PairTPHEqualTPH(TypePlaceholder tl, TypePlaceholder tr) {
         super(tl, tr);
     }
@@ -12,4 +16,24 @@ public class PairTPHEqualTPH extends ResultPair<TypePlaceholder, TypePlaceholder
     public void accept(ResultPairVisitor visitor) {
         visitor.visit(this);
     }
+
+    @Override
+    public SerialMap toSerial(KeyStorage keyStorage) {
+        SerialMap serialized = new SerialMap();
+        serialized.put("left", this.getLeft().toSerial(keyStorage));
+        serialized.put("right", this.getRight().toSerial(keyStorage));
+        // create the wrapper and put this as the object
+        var serializedWrapper = super.toSerial(keyStorage);
+        serializedWrapper.put("object", serialized);
+        return serializedWrapper;
+    }
+
+    public static PairTPHEqualTPH fromSerial2(SerialMap data, UnifyContext context) {
+        SerialMap left = data.getMap("left");
+        SerialMap right = data.getMap("right");
+        return new PairTPHEqualTPH(
+          (TypePlaceholder) RefTypeOrTPHOrWildcardOrGeneric.fromSerial(left, context),
+          (TypePlaceholder) RefTypeOrTPHOrWildcardOrGeneric.fromSerial(right, context)
+        );
+    }
 }

src/main/java/de/dhbwstuttgart/typeinference/result/PairTPHequalRefTypeOrWildcardType.java

@@ -1,13 +1,17 @@
 package de.dhbwstuttgart.typeinference.result;
 
-import de.dhbwstuttgart.syntaxtree.type.RefType;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
 import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 /**
  * Steht für A =. RefType
  */
-public class PairTPHequalRefTypeOrWildcardType extends ResultPair{
+public class PairTPHequalRefTypeOrWildcardType extends ResultPair<TypePlaceholder, RefTypeOrTPHOrWildcardOrGeneric>
+implements ISerializableData {
     public final TypePlaceholder left;
     public final RefTypeOrTPHOrWildcardOrGeneric right;
 
@@ -26,4 +30,24 @@ public class PairTPHequalRefTypeOrWildcardType extends ResultPair{
     public String toString() {
     	return "(" + left.toString() + " = " + right.toString() + ")";
     }
+
+    @Override
+    public SerialMap toSerial(KeyStorage keyStorage) {
+        SerialMap serialized = new SerialMap();
+        serialized.put("left", this.getLeft().toSerial(keyStorage));
+        serialized.put("right", this.getRight().toSerial(keyStorage));
+        // create the wrapper and put this as the object
+        var serializedWrapper = super.toSerial(keyStorage);
+        serializedWrapper.put("object", serialized);
+        return serializedWrapper;
+    }
+
+    public static PairTPHequalRefTypeOrWildcardType fromSerial2(SerialMap data, UnifyContext context) {
+        SerialMap left = data.getMap("left");
+        SerialMap right = data.getMap("right");
+        return new PairTPHequalRefTypeOrWildcardType(
+          (TypePlaceholder)RefTypeOrTPHOrWildcardOrGeneric.fromSerial(left, context),
+          RefTypeOrTPHOrWildcardOrGeneric.fromSerial(right, context)
+        );
+    }
 }

src/main/java/de/dhbwstuttgart/typeinference/result/PairTPHsmallerTPH.java

@@ -1,12 +1,17 @@
 package de.dhbwstuttgart.typeinference.result;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
 import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 /**
  * Steht für: A <. B
  */
-public class PairTPHsmallerTPH extends ResultPair{
+public class PairTPHsmallerTPH extends ResultPair<TypePlaceholder,TypePlaceholder>
+  implements ISerializableData {
     public final TypePlaceholder left;
     public final TypePlaceholder right;
     
@@ -14,7 +19,7 @@ public class PairTPHsmallerTPH extends ResultPair{
      * urspruengliches Paar aus diesem dieses Resultpair erzeugt wurde
      * wichtig fuer generated Generics
      */
-    ResultPair origPair;
+    ResultPair<?,?> origPair;
 
     public PairTPHsmallerTPH(TypePlaceholder left, TypePlaceholder right){
         super(left, right);
@@ -22,7 +27,7 @@ public class PairTPHsmallerTPH extends ResultPair{
         this.right = right;
     }
 
-    public PairTPHsmallerTPH(TypePlaceholder left, TypePlaceholder right, ResultPair origPair){
+    public PairTPHsmallerTPH(TypePlaceholder left, TypePlaceholder right, ResultPair<?,?> origPair){
     	this(left, right);
     	this.origPair = origPair;
     }
@@ -36,4 +41,24 @@ public class PairTPHsmallerTPH extends ResultPair{
     public String toString() {
     	return "(" + left.toString() + " < " + right.toString() + ")";
     }
+
+    @Override
+    public SerialMap toSerial(KeyStorage keyStorage) {
+        SerialMap serialized = new SerialMap();
+        serialized.put("left", this.getLeft().toSerial(keyStorage));
+        serialized.put("right", this.getRight().toSerial(keyStorage));
+        // create the wrapper and put this as the object
+        var serializedWrapper = super.toSerial(keyStorage);
+        serializedWrapper.put("object", serialized);
+        return serializedWrapper;
+    }
+
+    public static PairTPHsmallerTPH fromSerial2(SerialMap data, UnifyContext context) {
+        SerialMap left = data.getMap("left");
+        SerialMap right = data.getMap("right");
+        return new PairTPHsmallerTPH(
+          (TypePlaceholder) RefTypeOrTPHOrWildcardOrGeneric.fromSerial(left, context),
+          (TypePlaceholder) RefTypeOrTPHOrWildcardOrGeneric.fromSerial(right, context)
+        );
+    }
 }

src/main/java/de/dhbwstuttgart/typeinference/result/ResultPair.java

@@ -1,11 +1,17 @@
 package de.dhbwstuttgart.typeinference.result;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 /**
  * Paare, welche das Unifikationsergebnis darstellen
  */
-public abstract class ResultPair<A extends RefTypeOrTPHOrWildcardOrGeneric,B extends RefTypeOrTPHOrWildcardOrGeneric> {
+public abstract class ResultPair<A extends RefTypeOrTPHOrWildcardOrGeneric,B extends RefTypeOrTPHOrWildcardOrGeneric>
+implements ISerializableData {
     private final A left;
     private final B right;
 
@@ -58,5 +64,35 @@ public abstract class ResultPair<A extends RefTypeOrTPHOrWildcardOrGeneric,B ext
 			return false;
 		return true;
 	}
-   
+
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		String type = switch (this) {
+      case PairNoResult _ -> "pnr";
+      case PairTPHEqualTPH _ -> "ptet";
+      case PairTPHsmallerTPH _ -> "ptst";
+      case PairTPHequalRefTypeOrWildcardType _ -> "ptertwt";
+      default -> throw new RuntimeException("No type defined for ResultPair of class " + this.getClass().getName());
+    };
+    serialized.put("type", type);
+		// we only insert null for the object and expect the child classes to call this and override the value with themselves
+		serialized.put("object", SerialValue.NULL);
+		return serialized;
+	}
+
+	public static <A extends RefTypeOrTPHOrWildcardOrGeneric,B extends RefTypeOrTPHOrWildcardOrGeneric> ResultPair<A,B>
+	fromSerial(SerialMap data, UnifyContext context) {
+		String type = data.getValue("type").getOf(String.class);
+		SerialMap object = data.getMap("object");
+
+    return switch (type) {
+      case "pnr" -> (ResultPair) PairNoResult.fromSerial2(object, context);
+      case "ptet" -> (ResultPair) PairTPHEqualTPH.fromSerial2(object, context);
+      case "ptst" -> (ResultPair) PairTPHsmallerTPH.fromSerial2(object, context);
+      case "ptertwt" -> (ResultPair) PairTPHequalRefTypeOrWildcardType.fromSerial2(object, context);
+      default -> throw new RuntimeException("Could not unserialize class of unhandled type " + type);
+    };
+	}
 }

src/main/java/de/dhbwstuttgart/typeinference/result/ResultSet.java

@@ -1,5 +1,15 @@
 package de.dhbwstuttgart.typeinference.result;
 
+import com.google.common.collect.Ordering;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTaskHelper;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.util.Logger;
+import java.util.ArrayList;
+import java.util.Comparator;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -10,148 +20,179 @@ import de.dhbwstuttgart.syntaxtree.type.RefType;
 import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
 import de.dhbwstuttgart.syntaxtree.type.SuperWildcardType;
 import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
+import java.util.stream.Collectors;
 
 @SuppressWarnings("rawtypes")
-public class ResultSet {
+public class ResultSet implements ISerializableData {
 
-    public final Set<ResultPair> results;
-    public Set<ResultPair<TypePlaceholder, TypePlaceholder>> genIns;
+  public final Set<ResultPair> results;
+  public Set<ResultPair<TypePlaceholder, TypePlaceholder>> genIns;
 
-    public ResultSet(Set<ResultPair> set){
-        this.results = set;
-        this.genIns = new HashSet<>();
-        results.forEach(x -> { if (x instanceof PairTPHsmallerTPH) { this.genIns.add(x);}} );
-    }
-    
-    public boolean contains(ResultPair toCheck) {
-    	return this.results.contains(toCheck);
-    }
-    
-    public void remove(ResultPair toCheck) {
-    	results.remove(toCheck);
+  public ResultSet(Set<ResultPair> set) {
+    this.results = set;
+    this.genIns = TypeUnifyTaskHelper.getPresizedHashSet(results.size());
+    results.forEach(x -> {
+      if (x instanceof PairTPHsmallerTPH) {
+        this.genIns.add(x);
+      }
+    });
+  }
+
+  public boolean contains(ResultPair toCheck) {
+    return this.results.contains(toCheck);
+  }
+
+  public void remove(ResultPair toCheck) {
+    results.remove(toCheck);
+  }
+
+  public ResolvedType resolveType(RefTypeOrTPHOrWildcardOrGeneric type) {
+    if (type instanceof TypePlaceholder)
+      return new Resolver(this).resolve((TypePlaceholder) type);
+    if (type instanceof GenericRefType) return new ResolvedType(type, new HashSet<>());
+    if (type instanceof RefType) {
+      RelatedTypeWalker related = new RelatedTypeWalker(null, this);
+      type.accept(related);
+      return new ResolvedType(type, related.relatedTPHs);
+    } else {
+      throw new NotImplementedException();
+      //return new ResolvedType(type,new HashSet<>());
     }
+  }
 
-    public ResolvedType resolveType(RefTypeOrTPHOrWildcardOrGeneric type) {
-        if(type instanceof TypePlaceholder)
-            return new Resolver(this).resolve((TypePlaceholder)type);
-        if(type instanceof GenericRefType)return new ResolvedType(type, new HashSet<>());
-        if(type instanceof RefType) {
-            RelatedTypeWalker related = new RelatedTypeWalker(null, this);
-            type.accept(related);
-            return new ResolvedType(type, related.relatedTPHs);
-        } else {
-            throw new NotImplementedException();
-            //return new ResolvedType(type,new HashSet<>());
-        }
+  public String toString() {
+    var results = new ArrayList<>(this.results);
+    results.sort(
+      Comparator
+        .comparingInt((ResultPair o) -> o.getLeft().toString().length())
+        .thenComparing(o -> o.getLeft().toString())
+        .thenComparingInt(o -> o.getRight().toString().length())
+        .thenComparing(o -> o.getRight().toString())
+    );
+    return results.toString();
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o instanceof ResultSet other) {
+      // sort both result lists
+      var thisElements = new ArrayList<>(this.results);
+      thisElements.sort(Ordering.usingToString());
+      var otherElements = new ArrayList<>(other.results);
+      otherElements.sort(Ordering.usingToString());
+
+      return thisElements.equals(otherElements);
+    } else {
+      return false;
     }
+  }
 
-    public String toString() {
-    	return results.toString();
-    }
+  @Override
+  public int hashCode() {
+    return results.hashCode();
+  }
 
-	@Override
-	public boolean equals(Object o) {
-		if (o instanceof ResultSet) {
-			ResultSet other = (ResultSet)o;
-			return this.results.equals(other.results);
-		} else {
-			return false;
-		}
-	}
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();;
+    serialized.put("results", SerialList.fromMapped(results, result -> result.toSerial(keyStorage)));
+    return serialized;
+  }
 
-	@Override
-	public int hashCode() {
-		return results.hashCode();
-	}
+  public static ResultSet fromSerial(SerialMap data, UnifyContext context) {
+    var resultsData = data.getList("results").assertListOfMaps();
+    return new ResultSet(resultsData.stream().map(resultData -> ResultPair.fromSerial(resultData, context)).collect(Collectors.toSet()));
+  }
 }
 
 class Resolver implements ResultSetVisitor {
-    private final ResultSet result;
-    private TypePlaceholder toResolve;
-    private RefTypeOrTPHOrWildcardOrGeneric resolved;
-    private final Set<GenericInsertPair> additionalTPHs = new HashSet<>();
-    private ResultPair<?,?> currentPair;
+  private final ResultSet result;
+  private TypePlaceholder toResolve;
+  private RefTypeOrTPHOrWildcardOrGeneric resolved;
+  private final Set<GenericInsertPair> additionalTPHs = new HashSet<>();
+  private ResultPair<?, ?> currentPair;
 
-    public Resolver(ResultSet resultPairs){
-        this.result = resultPairs;
+  public static Logger logger = new Logger("Resolver");
+
+  public Resolver(ResultSet resultPairs) {
+    this.result = resultPairs;
+  }
+
+  public ResolvedType resolve(TypePlaceholder tph) {
+    toResolve = tph;
+    resolved = null;
+    logger.info(tph.toString());
+    for (ResultPair<?, ?> resultPair : result.results) {
+      if (resultPair instanceof PairTPHEqualTPH && ((PairTPHEqualTPH) resultPair).getLeft().equals(toResolve)) {
+        currentPair = resultPair;
+        return resolve(((PairTPHEqualTPH) resultPair).getRight());
+      }
+    }
+    for (ResultPair<?, ?> resultPair : result.results) {
+      currentPair = resultPair;
+      resultPair.accept(this);
+    }
+    if (resolved == null) {//TPH kommt nicht im Result vor:
+      resolved = tph;
     }
 
-    public ResolvedType resolve(TypePlaceholder tph){
-        toResolve = tph;
-        resolved = null;
-        System.out.println(tph.toString());
-        for(ResultPair<?,?> resultPair : result.results) {
-            if(resultPair instanceof PairTPHEqualTPH && ((PairTPHEqualTPH) resultPair).getLeft().equals(toResolve)){
-            	currentPair = resultPair;
-                return resolve(((PairTPHEqualTPH) resultPair).getRight());
-            }
-        }
-        for(ResultPair<?,?> resultPair : result.results){
-        	currentPair = resultPair;
-            resultPair.accept(this);
-        }
-        if(resolved==null){//TPH kommt nicht im Result vor:
-            resolved = tph;
-        }
+    ResolvedType result = new ResolvedType(resolved, additionalTPHs);//resolved;
+    result.setResultPair(currentPair);
+    return result;
+  }
 
-        ResolvedType result = new ResolvedType(resolved, additionalTPHs);//resolved;
-        result.setResultPair(currentPair);
-        return result;
+  @Override
+  public void visit(PairTPHsmallerTPH p) {
+    currentPair = p;
+    if (p.left.equals(toResolve)) {
+      additionalTPHs.add(new GenericInsertPair(p.left, p.right));
+      additionalTPHs.addAll(new RelatedTypeWalker(p.right, result).relatedTPHs);
     }
+    if (p.right.equals(toResolve))
+      additionalTPHs.addAll(new RelatedTypeWalker(p.left, result).relatedTPHs);
+  }
 
-    @Override
-    public void visit(PairTPHsmallerTPH p) {
-    	currentPair = p;
-        if(p.left.equals(toResolve)){
-            additionalTPHs.add(new GenericInsertPair(p.left, p.right));
-            additionalTPHs.addAll(new RelatedTypeWalker(p.right, result).relatedTPHs);
-        }
-        if(p.right.equals(toResolve))
-            additionalTPHs.addAll(new RelatedTypeWalker(p.left, result).relatedTPHs);
+  @Override
+  public void visit(PairTPHequalRefTypeOrWildcardType p) {
+    currentPair = p;
+    if (p.left.equals(toResolve)) {
+      resolved = p.right;
+      RelatedTypeWalker related = new RelatedTypeWalker(null, result);
+      p.right.accept(related);
+      additionalTPHs.addAll(related.relatedTPHs);
     }
+  }
 
-    @Override
-    public void visit(PairTPHequalRefTypeOrWildcardType p) {
-    	currentPair = p;
-        if(p.left.equals(toResolve)){
-            resolved = p.right;
-            RelatedTypeWalker related = new RelatedTypeWalker(null, result);
-            p.right.accept(related);
-            additionalTPHs.addAll(related.relatedTPHs);
-        }
-    }
+  @Override
+  public void visit(PairTPHEqualTPH p) {
+    //Do nothing. Dieser Fall wird in der resolve-Methode abgefangen
+  }
 
-    @Override
-    public void visit(PairTPHEqualTPH p) {
-        //Do nothing. Dieser Fall wird in der resolve-Methode abgefangen
-    }
+  @Override
+  public void visit(RefType refType) {
 
-    @Override
-    public void visit(RefType refType) {
+  }
 
-    }
+  @Override
+  public void visit(GenericRefType genericRefType) {
 
-    @Override
-    public void visit(GenericRefType genericRefType) {
+  }
 
-    }
+  @Override
+  public void visit(SuperWildcardType superWildcardType) {
 
-    @Override
-    public void visit(SuperWildcardType superWildcardType) {
+  }
 
-    }
+  @Override
+  public void visit(TypePlaceholder typePlaceholder) {
 
-    @Override
-    public void visit(TypePlaceholder typePlaceholder) {
+  }
 
-    }
+  @Override
+  public void visit(ExtendsWildcardType extendsWildcardType) {
 
-    @Override
-    public void visit(ExtendsWildcardType extendsWildcardType) {
+  }
 
-    }
-    
-    
 
 }
 
@@ -161,149 +202,150 @@ class Resolver implements ResultSetVisitor {
 @SuppressWarnings("rawtypes")
 class TPHResolver implements ResultSetVisitor {
 
-    private final TypePlaceholder tph;
-    Set<GenericInsertPair> resolved = new HashSet<>();
-    private final ResultSet resultSet;
+  private final TypePlaceholder tph;
+  Set<GenericInsertPair> resolved = new HashSet<>();
+  private final ResultSet resultSet;
 
-    TPHResolver(TypePlaceholder tph, ResultSet resultSet){
-        this.resultSet = resultSet;
-        this.tph = tph;
-        for(ResultPair p : resultSet.results){
-            p.accept(this);
-        }
-        if(resolved.size() == 0){
-            resolved.add(new GenericInsertPair(tph, null));
-        }
+  TPHResolver(TypePlaceholder tph, ResultSet resultSet) {
+    this.resultSet = resultSet;
+    this.tph = tph;
+    for (ResultPair p : resultSet.results) {
+      p.accept(this);
     }
-
-    @Override
-    public void visit(PairTPHsmallerTPH p) {
-        if(p.left.equals(tph) || p.right.equals(tph)){
-            resolved.add(new GenericInsertPair(p.left, p.right));
-        }
+    if (resolved.size() == 0) {
+      resolved.add(new GenericInsertPair(tph, null));
     }
+  }
 
-    @Override
-    public void visit(PairTPHequalRefTypeOrWildcardType p) {
-        TypePlaceholder otherSide = null;
-        if(p.right.equals(tph)){
-            otherSide = p.left;
-        }
-        if(otherSide != null){
-            Set<ResultPair> newResultSet = new HashSet<>(this.resultSet.results);
-            newResultSet.remove(p);
-            resolved.addAll(new TPHResolver(otherSide, new ResultSet(newResultSet)).resolved);
-        }
+  @Override
+  public void visit(PairTPHsmallerTPH p) {
+    if (p.left.equals(tph) || p.right.equals(tph)) {
+      resolved.add(new GenericInsertPair(p.left, p.right));
     }
+  }
 
-    @Override
-    public void visit(PairTPHEqualTPH p) {
-        //ignorieren. Wird vom Resolver behandelt
+  @Override
+  public void visit(PairTPHequalRefTypeOrWildcardType p) {
+    TypePlaceholder otherSide = null;
+    if (p.right.equals(tph)) {
+      otherSide = p.left;
     }
-
-    @Override
-    public void visit(RefType refType) {
-
+    if (otherSide != null) {
+      Set<ResultPair> newResultSet = new HashSet<>(this.resultSet.results);
+      newResultSet.remove(p);
+      resolved.addAll(new TPHResolver(otherSide, new ResultSet(newResultSet)).resolved);
     }
+  }
 
-    @Override
-    public void visit(GenericRefType genericRefType) {
+  @Override
+  public void visit(PairTPHEqualTPH p) {
+    //ignorieren. Wird vom Resolver behandelt
+  }
 
-    }
+  @Override
+  public void visit(RefType refType) {
 
-    @Override
-    public void visit(SuperWildcardType superWildcardType) {
+  }
 
-    }
+  @Override
+  public void visit(GenericRefType genericRefType) {
 
-    @Override
-    public void visit(TypePlaceholder typePlaceholder) {
+  }
 
-    }
+  @Override
+  public void visit(SuperWildcardType superWildcardType) {
 
-    @Override
-    public void visit(ExtendsWildcardType extendsWildcardType) {
+  }
 
-    }
+  @Override
+  public void visit(TypePlaceholder typePlaceholder) {
+
+  }
+
+  @Override
+  public void visit(ExtendsWildcardType extendsWildcardType) {
+
+  }
 }
 
 @SuppressWarnings("rawtypes")
 class RelatedTypeWalker implements ResultSetVisitor {
 
-    final Set<GenericInsertPair> relatedTPHs = new HashSet<>();
-    private final TypePlaceholder toResolve;
-    private final ResultSet resultSet;
+  final Set<GenericInsertPair> relatedTPHs = new HashSet<>();
+  private final TypePlaceholder toResolve;
+  private final ResultSet resultSet;
 
-    /**
-     * Läuft über das resultSet und speichert alle TPHs, welche mit start in Verbindung stehen
-     * @param start - kann null sein, wenn der Walker für einen RefType benutzt wird
-     * @param resultSet
-     */
-    RelatedTypeWalker(TypePlaceholder start, ResultSet resultSet){
-        this.toResolve = start;
-        this.resultSet = resultSet;
-        int resolved = 0;
-        do{
-            resolved = relatedTPHs.size();
-            for(ResultPair p : resultSet.results){
-                p.accept(this);
-                p.accept(this);
-            }
-        }while(resolved - relatedTPHs.size() > 0);
-    }
+  /**
+   * Läuft über das resultSet und speichert alle TPHs, welche mit start in Verbindung stehen
+   *
+   * @param start     - kann null sein, wenn der Walker für einen RefType benutzt wird
+   * @param resultSet
+   */
+  RelatedTypeWalker(TypePlaceholder start, ResultSet resultSet) {
+    this.toResolve = start;
+    this.resultSet = resultSet;
+    int resolved = 0;
+    do {
+      resolved = relatedTPHs.size();
+      for (ResultPair p : resultSet.results) {
+        p.accept(this);
+        p.accept(this);
+      }
+    } while (resolved - relatedTPHs.size() > 0);
+  }
 
-    @Override
-    public void visit(PairTPHsmallerTPH p) {
-        if(p.getRight().equals(toResolve)){
-            relatedTPHs.addAll(new TPHResolver(p.right, resultSet).resolved);
-            //relatedTPHs.addAll(new RelatedTypeWalker(p.right, resultSet).relatedTPHs);
-        }
-        if(p.getLeft().equals(toResolve)){
-            relatedTPHs.addAll(new TPHResolver(p.left, resultSet).resolved);
-            //relatedTPHs.addAll(new RelatedTypeWalker(p.left, resultSet).relatedTPHs);
-        }
+  @Override
+  public void visit(PairTPHsmallerTPH p) {
+    if (p.getRight().equals(toResolve)) {
+      relatedTPHs.addAll(new TPHResolver(p.right, resultSet).resolved);
+      //relatedTPHs.addAll(new RelatedTypeWalker(p.right, resultSet).relatedTPHs);
     }
+    if (p.getLeft().equals(toResolve)) {
+      relatedTPHs.addAll(new TPHResolver(p.left, resultSet).resolved);
+      //relatedTPHs.addAll(new RelatedTypeWalker(p.left, resultSet).relatedTPHs);
+    }
+  }
 
-    @Override
-    public void visit(PairTPHequalRefTypeOrWildcardType p) {
-        if(p.getLeft().equals(toResolve)){
-            p.getRight().accept(this);
-        }
+  @Override
+  public void visit(PairTPHequalRefTypeOrWildcardType p) {
+    if (p.getLeft().equals(toResolve)) {
+      p.getRight().accept(this);
     }
+  }
 
-    @Override
-    public void visit(PairTPHEqualTPH p) {
-        //Kann ignoriert werden. Diese Fälle werden vom Resolver behandelt
-    }
+  @Override
+  public void visit(PairTPHEqualTPH p) {
+    //Kann ignoriert werden. Diese Fälle werden vom Resolver behandelt
+  }
 
     /*
     Die folgenden Funktionen fügen alle TPHs an die relatedTPHs an, denen sie begegnen:
     Das wird verwendet, wenn alle relatedTPHs aus den Parametern eines RefTypes angefügt werden sollen
      */
 
-    @Override
-    public void visit(RefType refType) {
-        for(RefTypeOrTPHOrWildcardOrGeneric param : refType.getParaList()){
-            param.accept(this);
-        }
+  @Override
+  public void visit(RefType refType) {
+    for (RefTypeOrTPHOrWildcardOrGeneric param : refType.getParaList()) {
+      param.accept(this);
     }
+  }
 
-    @Override
-    public void visit(SuperWildcardType superWildcardType) {
-        superWildcardType.getInnerType().accept(this);
-    }
+  @Override
+  public void visit(SuperWildcardType superWildcardType) {
+    superWildcardType.getInnerType().accept(this);
+  }
 
-    @Override
-    public void visit(TypePlaceholder typePlaceholder) {
-        relatedTPHs.addAll(new TPHResolver(typePlaceholder, resultSet).resolved);
-    }
+  @Override
+  public void visit(TypePlaceholder typePlaceholder) {
+    relatedTPHs.addAll(new TPHResolver(typePlaceholder, resultSet).resolved);
+  }
 
-    @Override
-    public void visit(ExtendsWildcardType extendsWildcardType) {
-        extendsWildcardType.getInnerType().accept(this);
-    }
+  @Override
+  public void visit(ExtendsWildcardType extendsWildcardType) {
+    extendsWildcardType.getInnerType().accept(this);
+  }
 
-    @Override
-    public void visit(GenericRefType genericRefType) {
-    }
+  @Override
+  public void visit(GenericRefType genericRefType) {
+  }
 }

src/main/java/de/dhbwstuttgart/typeinference/typeAlgo/TYPE.java

@@ -14,6 +14,7 @@ import de.dhbwstuttgart.typeinference.assumptions.TypeInferenceBlockInformation;
 import de.dhbwstuttgart.typeinference.assumptions.TypeInferenceInformation;
 import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
 import de.dhbwstuttgart.typeinference.constraints.Pair;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTaskHelper;
 import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
 import de.dhbwstuttgart.util.BiRelation;
 import org.antlr.v4.runtime.Token;
@@ -33,7 +34,7 @@ public class TYPE {
     public ConstraintSet getConstraints() {
         ConstraintSet ret = new ConstraintSet();
         for (ClassOrInterface cl : sf.KlassenVektor) {
-            var allClasses = new HashSet<ClassOrInterface>();
+            Set<ClassOrInterface> allClasses = TypeUnifyTaskHelper.getPresizedHashSet(allAvailableClasses.size() + sf.availableClasses.size());
             allClasses.addAll(allAvailableClasses);
             allClasses.addAll(sf.availableClasses);
             ret.addAll(getConstraintsClass(cl, new TypeInferenceInformation(allClasses)));
@@ -68,7 +69,7 @@ public class TYPE {
 
             for(SourceFile sourceFile : sfs){
                 for(JavaClassName importName : sourceFile.imports){
-                    System.out.println(importName);
+                    context.logger().info(importName);
                     try {
                         classes.add(ASTFactory.createClass(classLoader.loadClass(importName.toString())));
                     } catch (ClassNotFoundException e) {

src/main/java/de/dhbwstuttgart/typeinference/typeAlgo/TYPEStmt.java

@@ -1,6 +1,8 @@
 //PL 2018-12-19: Merge chekcen
 package de.dhbwstuttgart.typeinference.typeAlgo;
 
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTaskHelper;
 import java.util.*;
 import java.util.stream.Collectors;
 
@@ -116,17 +118,18 @@ public class TYPEStmt implements StatementVisitor {
     @Override
     public void visit(FieldVar fieldVar) {
         fieldVar.receiver.accept(this);
-        Set<Constraint> oderConstraints = new HashSet<>();
+        List<FieldAssumption> fieldAssumptions = info.getFields(fieldVar.fieldVarName);
+        Set<Constraint> oderConstraints = TypeUnifyTaskHelper.getPresizedHashSet(fieldAssumptions.size());
 
 
-        for (FieldAssumption fieldAssumption : info.getFields(fieldVar.fieldVarName)) {
+        for (FieldAssumption fieldAssumption : fieldAssumptions) {
             Constraint constraint = new Constraint();
             GenericsResolver resolver = getResolverInstance();
             constraint.add(new Pair(fieldVar.receiver.getType(), fieldAssumption.getReceiverType(resolver), PairOperator.SMALLERDOT, loc(fieldVar.getOffset()))); // PL 2019-12-09: SMALLERDOT eingefuegt, EQUALSDOT entfernt, wenn ds Field privat ist muesste es EQUALSDOT lauten
             constraint.add(new Pair(fieldVar.getType(), fieldAssumption.getType(resolver), PairOperator.EQUALSDOT, loc(fieldVar.getOffset())));
             oderConstraints.add(constraint);
         }
-        if (oderConstraints.size() == 0)
+        if (oderConstraints.isEmpty())
             throw new TypeinferenceException("Kein Feld " + fieldVar.fieldVarName + " gefunden", fieldVar.getOffset());
         constraintsSet.addOderConstraint(oderConstraints);
     }
@@ -141,7 +144,7 @@ public class TYPEStmt implements StatementVisitor {
 
     @Override
     public void visit(ForEachStmt forEachStmt) {
-        var iterableType = new RefType(ASTFactory.createClass(java.lang.Iterable.class).getClassName(), Arrays.asList(new ExtendsWildcardType(forEachStmt.statement.getType(), new NullToken())), new NullToken());
+        var iterableType = new RefType(ASTFactory.createClass(java.lang.Iterable.class).getClassName(), List.of(new ExtendsWildcardType(forEachStmt.statement.getType(), new NullToken())), new NullToken());
         constraintsSet.addUndConstraint(new Pair(forEachStmt.expression.getType(), iterableType, PairOperator.SMALLERDOT, loc(forEachStmt.getOffset())));
         forEachStmt.statement.accept(this);
         forEachStmt.expression.accept(this);
@@ -189,7 +192,7 @@ public class TYPEStmt implements StatementVisitor {
         methodCall.receiver.accept(this);
         // Overloading:
         Set<Constraint<Pair>> methodConstraints = new HashSet<>();
-        for (MethodAssumption m : this.getMethods(methodCall.name, methodCall.arglist, info)) {
+        for (MethodAssumption m : TYPEStmt.getMethods(methodCall.name, methodCall.arglist, info)) {
             GenericsResolver resolver = getResolverInstance();
             Set<Constraint<Pair>> oneMethodConstraints = generateConstraint(methodCall, m, info, resolver);
             methodConstraints.addAll(oneMethodConstraints);
@@ -199,7 +202,7 @@ public class TYPEStmt implements StatementVisitor {
              * oneMethodConstraint.setExtendConstraint(extendsOneMethodConstraint); extendsOneMethodConstraint.setExtendConstraint(oneMethodConstraint); methodConstraints.add(extendsOneMethodConstraint);
              */
         }
-        if (methodConstraints.size() < 1) {
+        if (methodConstraints.isEmpty()) {
             throw new TypeinferenceException("Methode " + methodCall.name + " ist nicht vorhanden!", methodCall.getOffset());
         }
         constraintsSet.addOderConstraint(methodConstraints);
@@ -212,7 +215,7 @@ public class TYPEStmt implements StatementVisitor {
         for (MethodAssumption m : this.getConstructors(info, (RefType) methodCall.getType(), methodCall.getArgumentList())) {
             methodConstraints.add(generateConstructorConstraint(methodCall, m, info, getResolverInstance()));
         }
-        if (methodConstraints.size() < 1) {
+        if (methodConstraints.isEmpty()) {
             throw new TypeinferenceException("Konstruktor in Klasse " + methodCall.getType().toString() + " ist nicht vorhanden!", methodCall.getOffset());
         }
         constraintsSet.addOderConstraint(methodConstraints);
@@ -282,8 +285,13 @@ public class TYPEStmt implements StatementVisitor {
             // see: https://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.17
             // Expression muss zu Numeric Convertierbar sein. also von Numeric erben
             Constraint<Pair> numeric;
+            HashSet<JavaClassName> classNames = TypeUnifyTaskHelper.getPresizedHashSet(info.getAvailableClasses().size());
+            for (var classEl : info.getAvailableClasses()) {
+                classNames.add(classEl.getClassName());
+            }
+
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(bytee.getName())) {
+            if (classNames.contains(bytee.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), bytee, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), bytee, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -291,7 +299,7 @@ public class TYPEStmt implements StatementVisitor {
                 numericAdditionOrStringConcatenation.add(numeric);
             }
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(shortt.getName())) {
+            if (classNames.contains(shortt.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), shortt, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), shortt, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -299,7 +307,7 @@ public class TYPEStmt implements StatementVisitor {
                 numericAdditionOrStringConcatenation.add(numeric);
             }
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(integer.getName())) {
+            if (classNames.contains(integer.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), integer, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), integer, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -307,7 +315,7 @@ public class TYPEStmt implements StatementVisitor {
                 numericAdditionOrStringConcatenation.add(numeric);
             }
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(longg.getName())) {
+            if (classNames.contains(longg.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), longg, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), longg, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -315,7 +323,7 @@ public class TYPEStmt implements StatementVisitor {
                 numericAdditionOrStringConcatenation.add(numeric);
             }
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(floatt.getName())) {
+            if (classNames.contains(floatt.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), floatt, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), floatt, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -323,7 +331,7 @@ public class TYPEStmt implements StatementVisitor {
                 numericAdditionOrStringConcatenation.add(numeric);
             }
             // PL eingefuegt 2018-07-17
-            if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(doublee.getName())) {
+            if (classNames.contains(doublee.getName())) {
                 numeric = new Constraint<>();
                 numeric.add(new Pair(binary.lexpr.getType(), doublee, PairOperator.SMALLERDOT, loc(binary.getOffset())));
                 numeric.add(new Pair(binary.rexpr.getType(), doublee, PairOperator.SMALLERDOT, loc(binary.getOffset())));
@@ -338,7 +346,7 @@ public class TYPEStmt implements StatementVisitor {
 
             if (binary.operation.equals(BinaryExpr.Operator.ADD)) {
                 // Dann kann der Ausdruck auch das aneinanderfügen zweier Strings sein: ("a" + "b") oder (1 + 2)
-                if (info.getAvailableClasses().stream().map(x -> x.getClassName()).collect(Collectors.toCollection(HashSet::new)).contains(string.getName())) {
+                if (classNames.contains(string.getName())) {
                     Constraint<Pair> stringConcat = new Constraint<>();
                     stringConcat.add(new Pair(binary.lexpr.getType(), string, PairOperator.EQUALSDOT, loc(binary.getOffset())));
                     stringConcat.add(new Pair(binary.rexpr.getType(), string, PairOperator.EQUALSDOT, loc(binary.getOffset())));
@@ -346,7 +354,7 @@ public class TYPEStmt implements StatementVisitor {
                     numericAdditionOrStringConcatenation.add(stringConcat);
                 }
             }
-            if (numericAdditionOrStringConcatenation.size() < 1) {
+            if (numericAdditionOrStringConcatenation.isEmpty()) {
                 throw new TypeinferenceException("Kein Typ für " + binary.operation.toString() + " vorhanden", binary.getOffset());
             }
             constraintsSet.addOderConstraint(numericAdditionOrStringConcatenation);
@@ -693,8 +701,8 @@ public class TYPEStmt implements StatementVisitor {
 
         Set<Pair> methodSignatureConstraint = generatemethodSignatureConstraint(forMethod, assumption, info, resolver);
 
-        //System.out.println("methodSignatureConstraint: " + methodSignatureConstraint);
-        //System.out.println("methodConstraint: " + methodConstraint);
+        //context.logger().info("methodSignatureConstraint: " + methodSignatureConstraint);
+        //context.logger().info("methodConstraint: " + methodConstraint);
 
         methodConstraint.setmethodSignatureConstraint(methodSignatureConstraint);
         extendsMethodConstraint.setmethodSignatureConstraint(methodSignatureConstraint);
@@ -732,7 +740,7 @@ public class TYPEStmt implements StatementVisitor {
         }
 
         // Zuordnung von MethodCall.signature(ReturnType) zu dem ReturnType der ausgewaehlten Methode (assumption.returnType)
-        ret.add(new Pair(foMethod.signature.get(foMethod.signature.size() - 1), assumption.getReturnType(), PairOperator.EQUALSDOT));
+        ret.add(new Pair(foMethod.signature.getLast(), assumption.getReturnType(), PairOperator.EQUALSDOT));
         return ret;
     }
 
@@ -745,8 +753,8 @@ public class TYPEStmt implements StatementVisitor {
                 // funNParams.add(TypePlaceholder.fresh(new NullToken()));
                 funNParams.add(new GenericRefType(NameGenerator.makeNewName(), new NullToken()));
             }
-            funNParams.get(funNParams.size() - 1);
-            ret.add(new MethodAssumption(new FunNClass(funNParams), funNParams.get(funNParams.size() - 1), funNParams.subList(0, funNParams.size() - 1), new TypeScope() {
+            funNParams.getLast();
+            ret.add(new MethodAssumption(new FunNClass(funNParams), funNParams.getLast(), funNParams.subList(0, funNParams.size() - 1), new TypeScope() {
                 @Override
                 public Iterable<? extends GenericTypeVar> getGenerics() {
                     throw new NotImplementedException();
@@ -841,7 +849,7 @@ public class TYPEStmt implements StatementVisitor {
             for (var child : switchStmt.getBlocks()) {
                 for (var label : child.getLabels()) {
                     if (label.getPattern() == null) {
-                        //System.out.println("DefaultCase");
+                        //context.logger().info("DefaultCase");
                     } else {
                         constraintsSet.addUndConstraint(
                                 new Pair(
@@ -882,13 +890,9 @@ public class TYPEStmt implements StatementVisitor {
 
             child.getLabels().forEach(el -> {
                 if (el.getType() instanceof RefType) {
-                    var recType = el;
-
-                    if (el.getPattern() instanceof RecordPattern) {
-                        var pattern = (RecordPattern) recType.getPattern();
-                        recursivelyAddRecordConstraints(pattern);
-                    }
-
+                  if (el.getPattern() instanceof RecordPattern pattern) {
+                    recursivelyAddRecordConstraints(pattern);
+                  }
                 }
             });
 
@@ -904,13 +908,13 @@ public class TYPEStmt implements StatementVisitor {
 
         var allClasses = info.getAvailableClasses();
         var interestingClasses = allClasses.stream().filter(as -> as.getClassName().equals(((RefType) pattern.getType()).getName())).toList();
-        var constructors = interestingClasses.get(0).getConstructors();
+        var constructors = interestingClasses.getFirst().getConstructors();
 
         int counter = 0;
 
         for (var subPattern : pattern.getSubPattern()) {
             for (Constructor con : constructors) {
-                //System.out.println("----------------------\n" + subPattern.getType() + " | " + con.getParameterList().getParameterAt(counter).getType() + "\n----------------------\n");
+                //context.logger().info("----------------------\n" + subPattern.getType() + " | " + con.getParameterList().getParameterAt(counter).getType() + "\n----------------------\n");
                 constraintsSet.addUndConstraint(new Pair(subPattern.getType(), con.getParameterList().getParameterAt(counter).getType(), PairOperator.SMALLERDOT, loc(con.getParameterList().getParameterAt(counter).getOffset())));
             }
             if (subPattern instanceof RecordPattern) recursivelyAddRecordConstraints((RecordPattern) subPattern);

src/main/java/de/dhbwstuttgart/typeinference/unify/CancellableTask.java

@@ -0,0 +1,91 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.RecursiveTask;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * An intermediate class for the recursive steps of the TypeUnifyTask:
+ * This allows canceling parts of the recursion tree, instead of only  the whole execution as before. But in
+ * order for that to work, all cancellable child tasks must be added when they are created
+ *
+ * @param <T>
+ */
+public abstract class CancellableTask<T> extends RecursiveTask<T> {
+
+  private final AtomicBoolean executionCancelled = new AtomicBoolean(false);
+  private final List<CancellableTask<?>> childTasks = new LinkedList<>();
+  private CancellableTask<?> parentTask = null;
+
+  /**
+   * Set the execution for this task and all its (recursive) children to be canceled
+   */
+  protected void cancelExecution() {
+    // is this branch already canceled? Then do nothing
+    if (this.executionCancelled.getAndSet(true)) return;
+    this.cancelChildExecution();
+  }
+
+  private void cancelChildExecution() {
+    synchronized (this.childTasks) {
+      for (var childTask : childTasks) {
+        // no need to cancel a branch that is already finished
+        if (!childTask.isDone()) {
+          childTask.cancelExecution();
+        }
+      }
+    }
+  }
+
+  private void cancelChildExecutionAfter(CancellableTask<?> checkpointTask) {
+    boolean reachedCheckpoint = false;
+    int i = 0;
+    for (var childTask : childTasks) {
+      if (!reachedCheckpoint) {
+        reachedCheckpoint = childTask == checkpointTask;
+      }
+      else {
+        // no need to cancel a branch that is already finished
+        if (!childTask.isDone()) {
+          childTask.cancelExecution();
+        }
+        i++;
+      }
+    }
+    System.out.println("Skipped " + i + " younger siblings");
+  }
+
+  protected void cancelSiblingTasks() {
+    if (this.parentTask != null) {
+      boolean thisWasCancelledBefore = this.executionCancelled.get();
+      this.parentTask.cancelChildExecution();
+      this.executionCancelled.set(thisWasCancelledBefore);
+    }
+  }
+
+  public void cancelYoungerSiblingTasks() {
+    if (this.parentTask != null) {
+      this.parentTask.cancelChildExecutionAfter(this);
+    }
+  }
+
+  public Boolean isExecutionCancelled() {
+    return executionCancelled.get();
+  }
+
+  public void addChildTask(CancellableTask<?> childTask) {
+    this.childTasks.add(childTask);
+    childTask.setParentTask(this);
+    if (this.executionCancelled.get()) {
+      childTask.executionCancelled.set(true);
+    }
+  }
+
+  private void setParentTask(CancellableTask<?> parentTask) {
+    this.parentTask = parentTask;
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/ConcurrentSetMergeTask.java

@@ -0,0 +1,61 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.RecursiveTask;
+
+public class ConcurrentSetMergeTask<T> extends RecursiveTask<Set<T>> {
+
+  public static <E> Set<E> merge(List<Set<E>> list) {
+    if (list.isEmpty()) {
+      return new HashSet<>();
+    }
+    var task = new ConcurrentSetMergeTask<>(list, 0, list.size());
+    return task.compute();
+  }
+
+  private static final int LIST_THRESHOLD = 3;
+  private static final int ELEMENT_THRESHOLD = 1000;
+
+  private final List<Set<T>> list;
+  private final int start;
+  private final int end;
+
+  private ConcurrentSetMergeTask(List<Set<T>> list, int start, int end) {
+    this.list = list;
+    this.start = start;
+    this.end = end;
+  }
+
+  @Override
+  protected Set<T> compute() {
+    int size = end - start;
+
+    int totalElements = 0;
+    for (int i = start+1; i < end; i++) {
+      totalElements += list.get(i).size();
+    }
+
+    // size will always be at least one
+    if (true || size <= LIST_THRESHOLD || totalElements < ELEMENT_THRESHOLD) {
+      Set<T> result = this.list.get(start);
+      for (int i = start+1; i < end; i++) {
+        result.addAll(list.get(i));
+      }
+      return result;
+    } else {
+      int mid = start + (size / 2);
+      ConcurrentSetMergeTask<T> leftTask = new ConcurrentSetMergeTask<>(list, start, mid);
+      ConcurrentSetMergeTask<T> rightTask = new ConcurrentSetMergeTask<>(list, mid, end);
+
+      leftTask.fork();
+      Set<T> rightResult = rightTask.compute();
+      Set<T> leftResult = leftTask.join();
+
+      // Merge results
+      leftResult.addAll(rightResult);
+      return leftResult;
+    }
+  }
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/MartelliMontanariUnify.java

@@ -94,8 +94,8 @@ public class MartelliMontanariUnify implements IUnify {
 			// SUBST - Rule
 			if(lhsType instanceof PlaceholderType) {
 				mgu.add((PlaceholderType) lhsType, rhsType);
-				//PL 2018-04-01 nach checken, ob es richtig ist, dass keine Substitutionen uebergeben werden muessen. 
-				termsList = termsList.stream().map(x -> mgu.apply(x)).collect(Collectors.toCollection(ArrayList::new));
+				//PL 2018-04-01 nach checken, ob es richtig ist, dass keine Substitutionen uebergeben werden muessen.
+				termsList.replaceAll(mgu::apply);
 				idx = idx+1 == termsList.size() ? 0 : idx+1;
 				continue;
 			}

src/main/java/de/dhbwstuttgart/typeinference/unify/PlaceholderRegistry.java

@@ -0,0 +1,84 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
+import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
+import java.util.ArrayList;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Calculate unique placeholder names
+ */
+public class PlaceholderRegistry implements ISerializableData {
+
+  private final Set<String> existingPlaceholders = ConcurrentHashMap.newKeySet();
+  private final AtomicInteger placeholderCount = new AtomicInteger();
+  public ArrayList<PlaceholderType> UnifyTypeFactory_PLACEHOLDERS = new ArrayList<>();
+
+  /**
+   * Add a placeholder into the list of existing ones, as soon as a new PlaceholderType is created
+   *
+   * @param placeholderName The placeholder to add
+   */
+  public void addPlaceholder(String placeholderName) {
+    this.existingPlaceholders.add(placeholderName);
+  }
+
+  /**
+   * Generate a random placeholder name, that is unique to this context
+   *
+   * @return  The generated name
+   */
+  public String generateFreshPlaceholderName() {
+    String name;
+    do {
+      int pc = placeholderCount.incrementAndGet();
+      name = getUppercaseTokenFromInt(pc);
+    }
+    while (existingPlaceholders.contains(name));
+    this.addPlaceholder(name);
+    return name;
+  }
+
+  public PlaceholderRegistry deepClone() {
+    PlaceholderRegistry pr2 = new PlaceholderRegistry();
+    this.existingPlaceholders.forEach(pr2::addPlaceholder);
+    pr2.UnifyTypeFactory_PLACEHOLDERS.addAll(this.UnifyTypeFactory_PLACEHOLDERS);
+    pr2.placeholderCount.set(this.placeholderCount.get());
+    return pr2;
+  }
+
+  /**
+   * Generate a token that consists of uppercase letters and contains the given prefix and suffix from the value i
+   *
+   * @param i       The value that will be represented as a token
+   * @return        The generated token
+   */
+  private String getUppercaseTokenFromInt(int i) {
+    StringBuilder sb = new StringBuilder();
+    while (i >= 0) {
+      sb.append((char)(i % 26 + 65));
+      i = i / 26 - 1;
+    }
+    //sb.append(suffix);
+    return sb.toString();
+  }
+
+  @Override
+  public String toString() {
+    return this.existingPlaceholders.toString();
+  }
+
+  @Override
+  public SerialMap toSerial(KeyStorage keyStorage) {
+    SerialMap serialized = new SerialMap();
+    serialized.put("ph", new SerialValue<>(new ArrayList<>(this.existingPlaceholders)));
+    serialized.put("factoryPh", SerialList.fromMapped(this.UnifyTypeFactory_PLACEHOLDERS, t -> t.toSerial(keyStorage)));
+    return serialized;
+  }
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/RuleSet.java

@@ -1,10 +1,12 @@
 package de.dhbwstuttgart.typeinference.unify;
 
+import de.dhbwstuttgart.util.Logger;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.ListIterator;
 import java.util.Optional;
 import java.util.Queue;
 import java.util.Set;
@@ -12,24 +14,16 @@ import java.util.Stack;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
-import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.exceptions.DebugException;
-import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
-import de.dhbwstuttgart.syntaxtree.type.ExtendsWildcardType;
-import de.dhbwstuttgart.syntaxtree.type.RefType;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IRuleSet;
 import de.dhbwstuttgart.typeinference.unify.model.*;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
-import de.dhbwstuttgart.typeinference.unify.distributeVariance;
 
-import java.io.FileWriter;
 import java.io.IOException;
 import java.io.Writer;
 import java.io.OutputStreamWriter;
 
-import org.apache.commons.io.output.NullOutputStream;
-
 /**
  * Implementation of the type inference rules.
  * @author Florian Steurer
@@ -37,15 +31,18 @@ import org.apache.commons.io.output.NullOutputStream;
  */
 public class RuleSet implements IRuleSet{
 	
-	Writer logFile;
+	Logger logger;
+	final PlaceholderRegistry placeholderRegistry;
 	
-	public RuleSet() {
+	public RuleSet(PlaceholderRegistry placeholderRegistry) {
 		super();
-		logFile = new OutputStreamWriter(new NullOutputStream());
+		logger = Logger.NULL_LOGGER;
+		this.placeholderRegistry = placeholderRegistry;
 	}
 	
-	RuleSet(Writer logFile) {
-		this.logFile = logFile;
+	RuleSet(Logger logger, PlaceholderRegistry placeholderRegistry) {
+		this.logger = logger;
+		this.placeholderRegistry = placeholderRegistry;
 	}
 	
 	@Override
@@ -297,8 +294,8 @@ public class RuleSet implements IRuleSet{
 		
 		if(dFromFc == null || !dFromFc.getTypeParams().arePlaceholders() || dFromFc.getTypeParams().size() != cFromFc.getTypeParams().size())
 			return Optional.empty();
-		//System.out.println("cFromFc: " + cFromFc);
-		//System.out.println("dFromFc: " + dFromFc);
+		//context.logger().info("cFromFc: " + cFromFc);
+		//context.logger().info("dFromFc: " + dFromFc);
 		int[] pi = pi(cFromFc.getTypeParams(), dFromFc.getTypeParams());
 		
 		if(pi.length == 0)
@@ -507,17 +504,17 @@ public class RuleSet implements IRuleSet{
 		TypeParams typeDParams = typeD.getTypeParams();
 		TypeParams typeDgenParams = typeDgen.getTypeParams();
 		
-		//System.out.println("Pair: " +pair);
-		//System.out.println("typeD: " +typeD);
-		//System.out.println("typeDParams: " +typeDParams);
-		//System.out.println("typeDgen: " +typeD);
-		//System.out.println("typeDgenParams: " +typeDgenParams);
+		//context.logger().info("Pair: " +pair);
+		//context.logger().info("typeD: " +typeD);
+		//context.logger().info("typeDParams: " +typeDParams);
+		//context.logger().info("typeDgen: " +typeD);
+		//context.logger().info("typeDgenParams: " +typeDgenParams);
 		Unifier unif = Unifier.identity();
 		for(int i = 0; i < typeDParams.size(); i++) { 
-			//System.out.println("ADAPT" +typeDgenParams);
+			//context.logger().info("ADAPT" +typeDgenParams);
 			if (typeDgenParams.get(i) instanceof PlaceholderType) 
-			unif.add((PlaceholderType) typeDgenParams.get(i), typeDParams.get(i));
-			else System.out.println("ERROR");
+				unif.add((PlaceholderType) typeDgenParams.get(i), typeDParams.get(i));
+			else logger.exception(new Exception("ERROR in adapt rule: cannot add non placeholder type"));
 		}
 		return Optional.of(new UnifyPair(unif.apply(newLhs), typeDs, PairOperator.SMALLERDOT, pair.getSubstitution(), pair.getBasePair()));
 	}
@@ -652,15 +649,17 @@ public class RuleSet implements IRuleSet{
 	
 	@Override
 	public Optional<Set<UnifyPair>> subst(Set<UnifyPair> pairs, List<Set<Constraint<UnifyPair>>> oderConstraints) {
-		HashMap<UnifyType, Integer> typeMap = new HashMap<>();
+		// Statistically, typeMap will fill up quickly and resize multiple times. To reduce this, we start with a higher capacity
+		HashMap<UnifyType, Integer> typeMap = new HashMap<>(200);
 		
 		Stack<UnifyType> occuringTypes = new Stack<>();
-		
+		occuringTypes.ensureCapacity(pairs.size() * 3);
+
 		for(UnifyPair pair : pairs) {
 			occuringTypes.push(pair.getLhsType());
 			occuringTypes.push(pair.getRhsType());
 		}
-		
+
 		while(!occuringTypes.isEmpty()) {
 			UnifyType t1 = occuringTypes.pop();
 			if(!typeMap.containsKey(t1))
@@ -672,12 +671,12 @@ public class RuleSet implements IRuleSet{
 			if(t1 instanceof SuperType)
 				occuringTypes.push(((SuperType) t1).getSuperedType());
 			else
-				t1.getTypeParams().forEach(x -> occuringTypes.push(x));	
+				t1.getTypeParams().forEach(occuringTypes::push);
 		}
-		Queue<UnifyPair> result1 = new LinkedList<UnifyPair>(pairs);
+		LinkedList<UnifyPair> result1 = new LinkedList<UnifyPair>(pairs);
 		ArrayList<UnifyPair> result = new ArrayList<UnifyPair>();
 		boolean applied = false;
-		
+
 		while(!result1.isEmpty()) {
 			UnifyPair pair = result1.poll();
 			PlaceholderType lhsType = null;
@@ -695,19 +694,30 @@ public class RuleSet implements IRuleSet{
 					&& !((rhsType instanceof WildcardType) && ((WildcardType)rhsType).getWildcardedType().equals(lhsType))) //PL eigefuegt 2018-02-18
 			{
 				Unifier uni = new Unifier(lhsType,  rhsType);
-				result = result.stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(ArrayList::new));
-				result1 = result1.stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(LinkedList::new));
-				
+				// apply unifier to result and result1 in place
+				result.replaceAll(p -> uni.apply(pair, p));
+				ListIterator<UnifyPair> result1Iterator = result1.listIterator();
+				while (result1Iterator.hasNext()) {
+					UnifyPair x = result1Iterator.next();
+					result1Iterator.set(uni.apply(pair, x));
+				}
+
 				Function<? super Constraint<UnifyPair>,? extends Constraint<UnifyPair>> applyUni = b -> b.stream().map(
 						x -> uni.apply(pair,x)).collect(Collectors.toCollection((b.getExtendConstraint() != null)
 								? () -> new Constraint<UnifyPair>(
 										  b.isInherited(),
 										  b.isImplemented(),
-										  b.getExtendConstraint().stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(Constraint::new)),
+										  b.getExtendConstraint().createdMapped(x -> uni.apply(pair,x)),
 										  b.getmethodSignatureConstraint().stream().map(x -> uni.apply(pair,x)).collect(Collectors.toCollection(HashSet::new)))
 								: () -> new Constraint<UnifyPair>(b.isInherited(), b.isImplemented())
 									));
-				oderConstraints.replaceAll(oc -> oc.stream().map(applyUni).collect(Collectors.toCollection(HashSet::new)));
+				oderConstraints.replaceAll(oc -> {
+						HashSet<Constraint<UnifyPair>> mapped = new HashSet<>(oc.size());
+						for (var element : oc) {
+							mapped.add(applyUni.apply(element));
+						}
+						return mapped;
+				});
 				/*
 						oderConstraints = oderConstraints.stream().map(
 						a -> a.stream().map(applyUni
@@ -861,14 +871,11 @@ public class RuleSet implements IRuleSet{
         								   UnifyType r = x.getRhsType();
         								   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 								     } );
-		try {
-			logFile.write("FUNgreater: " + pair + "\n");
-				logFile.write("FUNred: " + result + "\n");
-				logFile.flush();
-			}
-		catch (IOException e) {
-			System.out.println("logFile-Error");
-		}
+
+		logger.debug(() -> "FUNgreater: " + pair);
+		logger.debug(() -> "FUNred: " + result);
+
+
 		return Optional.of(result);
 	}
 	
@@ -934,15 +941,15 @@ public class RuleSet implements IRuleSet{
 
 		Set<UnifyPair> result = new HashSet<UnifyPair>();
 		
-		Integer variance = ((PlaceholderType)rhsType).getVariance();
-		Integer inversVariance = distributeVariance.inverseVariance(variance);
+		int variance = ((PlaceholderType)rhsType).getVariance();
+		int inversVariance = distributeVariance.inverseVariance(variance);
 		
 		UnifyType[] freshPlaceholders = new UnifyType[funNLhsType.getTypeParams().size()];
 		for(int i = 0; i < freshPlaceholders.length-1; i++) {
-			freshPlaceholders[i] = PlaceholderType.freshPlaceholder();
+			freshPlaceholders[i] = PlaceholderType.freshPlaceholder(placeholderRegistry);
 			((PlaceholderType)freshPlaceholders[i]).setVariance(inversVariance);
 		}
-		freshPlaceholders[freshPlaceholders.length-1] = PlaceholderType.freshPlaceholder();
+		freshPlaceholders[freshPlaceholders.length-1] = PlaceholderType.freshPlaceholder(placeholderRegistry);
 		((PlaceholderType)freshPlaceholders[freshPlaceholders.length-1]).setVariance(variance);
 		result.add(new UnifyPair(funNLhsType.getTypeParams().get(funNLhsType.getTypeParams().size()-1), freshPlaceholders[funNLhsType.getTypeParams().size()-1], PairOperator.SMALLERDOT, pair.getSubstitution(), pair.getBasePair()));
 		
@@ -953,18 +960,14 @@ public class RuleSet implements IRuleSet{
 		result.add(new UnifyPair(rhsType, funNLhsType.setTypeParams(new TypeParams(freshPlaceholders)), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		
 		result.stream().forEach(x -> { UnifyType l = x.getLhsType();
-									   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); } 
+									   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); }
 									   UnifyType r = x.getRhsType();
 									   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 									 } );
-		try {
-			logFile.write("FUNgreater: " + pair + "\n");
-			logFile.write("FUNgreater: " + result + "\n");
-			logFile.flush();
-		}
-	catch (IOException e) {
-		System.out.println("lofFile-Error");
-	}
+
+		logger.debug(() -> "FUNgreater: " + pair);
+		logger.debug(() -> "FUNgreater: " + result);
+
 		return Optional.of(result);
 	}
 
@@ -983,15 +986,15 @@ public class RuleSet implements IRuleSet{
 
 		Set<UnifyPair> result = new HashSet<UnifyPair>();
 		
-		Integer variance = ((PlaceholderType)lhsType).getVariance();
-		Integer inversVariance = distributeVariance.inverseVariance(variance);
+		int variance = ((PlaceholderType)lhsType).getVariance();
+		int inversVariance = distributeVariance.inverseVariance(variance);
 		
 		UnifyType[] freshPlaceholders = new UnifyType[funNRhsType.getTypeParams().size()];
 		for(int i = 0; i < freshPlaceholders.length-1; i++) {
-			freshPlaceholders[i] = PlaceholderType.freshPlaceholder();
+			freshPlaceholders[i] = PlaceholderType.freshPlaceholder(placeholderRegistry);
 			((PlaceholderType)freshPlaceholders[i]).setVariance(inversVariance);
 		}
-		freshPlaceholders[freshPlaceholders.length-1] = PlaceholderType.freshPlaceholder();
+		freshPlaceholders[freshPlaceholders.length-1] = PlaceholderType.freshPlaceholder(placeholderRegistry);
 		((PlaceholderType)freshPlaceholders[freshPlaceholders.length-1]).setVariance(variance);
 		
 		result.add(new UnifyPair(freshPlaceholders[funNRhsType.getTypeParams().size()-1], funNRhsType.getTypeParams().get(funNRhsType.getTypeParams().size()-1), PairOperator.SMALLERDOT, pair.getSubstitution(), pair.getBasePair()));
@@ -1003,18 +1006,15 @@ public class RuleSet implements IRuleSet{
 		result.add(new UnifyPair(lhsType, funNRhsType.setTypeParams(new TypeParams(freshPlaceholders)), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		
 		result.stream().forEach(x -> { UnifyType l = x.getLhsType();
-		   							   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); } 
+		   							   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); }
 		   							   UnifyType r = x.getRhsType();
 		   							   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 									 } );
-		try {
-			logFile.write("FUNgreater: " + pair + "\n");
-			logFile.write("FUNsmaller: " + result + "\n");
-			logFile.flush();
-		}
-	catch (IOException e) {
-		System.out.println("lofFile-Error");
-	}
+
+
+		logger.debug(() -> "FUNgreater: " + pair);
+		logger.debug(() -> "FUNsmaller: " + result);
+
 		return Optional.of(result);
 	}
 
@@ -1051,7 +1051,7 @@ public class RuleSet implements IRuleSet{
 		if(isGen)
 			result.add(new UnifyPair(rhsType, lhsType, PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		else {
-			UnifyType freshTph = PlaceholderType.freshPlaceholder();
+			UnifyType freshTph = PlaceholderType.freshPlaceholder(placeholderRegistry);
 			result.add(new UnifyPair(rhsType, new ExtendsType(freshTph), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 			result.add(new UnifyPair(extendedType, freshTph, PairOperator.SMALLERDOT, pair.getSubstitution(), pair.getBasePair()));
 		}
@@ -1079,7 +1079,7 @@ public class RuleSet implements IRuleSet{
 		if(isGen)
 			result.add(new UnifyPair(rhsType, lhsType, PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		else {
-			UnifyType freshTph = PlaceholderType.freshPlaceholder();
+			UnifyType freshTph = PlaceholderType.freshPlaceholder(placeholderRegistry);
 			result.add(new UnifyPair(rhsType, new SuperType(freshTph), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 			Set<UnifyType> fBounded = pair.getfBounded();
 			fBounded.add(lhsType);

src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnify.java

@@ -1,90 +1,65 @@
 package de.dhbwstuttgart.typeinference.unify;
 
-import java.io.FileWriter;
+import de.dhbwstuttgart.util.Logger;
 import java.io.IOException;
-import java.io.Writer;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ForkJoinPool;
 
-import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
-import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
-import de.dhbwstuttgart.typeinference.constraints.Pair;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
-import de.dhbwstuttgart.typeinference.unify.model.FiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
 
 public class TypeUnify {
-	
+
+	private TypeUnify() {}
+
+	private static <T> T joinFuture(CompletableFuture<T> future) {
+		try {
+			return future.get();
+		}
+		catch (InterruptedException | ExecutionException exception) {
+			throw new RuntimeException(exception);
+		}
+	}
+
 	/**
 	 * unify parallel ohne result modell
-	 * @param undConstrains
-	 * @param oderConstraints
-	 * @param fc
-	 * @param logFile
-	 * @param log
-	 * @param cons
-	 * @return
 	 */
-	public Set<Set<UnifyPair>> unify(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, Writer logFile, Boolean log, UnifyResultModel ret, UnifyTaskModel usedTasks) {
-		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, true, logFile, log, 0, ret, usedTasks);
-		ForkJoinPool pool = new ForkJoinPool();
-		pool.invoke(unifyTask);
-		Set<Set<UnifyPair>> res =  unifyTask.join();
-		try {
-			logFile.write("\nnoShortendElements: " + unifyTask.noShortendElements + "\n");
-			logFile.flush();
-		}
-		catch (IOException e) {
-			System.err.println("no log-File");
-		}
+	public static Set<Set<UnifyPair>> unify(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, UnifyContext unifyContext) {
+		ForkJoinPool pool = TypeUnify.createThreadPool(unifyContext.logger());
+		UnifyContext context = unifyContext.newWithParallel(true).newWithExecutor(pool);
+		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, context, 0);
+		Set<Set<UnifyPair>> res = joinFuture(unifyTask.compute());
+
+		unifyContext.logger().debug("\nnoShortendElements: " + TypeUnifyTask.noShortendElements + "\n");
 		return res;
 	}
 	
 	/**
 	 * unify asynchron mit Rückgabe UnifyResultModel ohne dass alle results gesammelt sind
-	 * @param undConstrains
-	 * @param oderConstraints
-	 * @param fc
-	 * @param logFile
-	 * @param log
-	 * @param cons
-	 * @param ret
-	 * @return
 	 */
-	public UnifyResultModel unifyAsync(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, Writer logFile, Boolean log, UnifyResultModel ret, UnifyTaskModel usedTasks) {
-		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, true, logFile, log, 0, ret, usedTasks);
-		ForkJoinPool pool = new ForkJoinPool();
-		pool.invoke(unifyTask);
-		return ret;
+	public static UnifyResultModel unifyAsync(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, UnifyContext unifyContext) {
+		ForkJoinPool pool = TypeUnify.createThreadPool(unifyContext.logger());
+		UnifyContext context = unifyContext.newWithExecutor(pool);
+		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, context, 0);
+		unifyTask.compute();
+		return unifyContext.resultModel();
 	}
-	
+
 	/**
 	 * unify parallel mit Rückgabe UnifyResultModel nachdem alle results gesammelt sind
-	 * @param undConstrains
-	 * @param oderConstraints
-	 * @param fc
-	 * @param logFile
-	 * @param log
-	 * @param cons
-	 * @param ret
-	 * @return
 	 */
-	public UnifyResultModel unifyParallel(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, Writer logFile, Boolean log, UnifyResultModel ret, UnifyTaskModel usedTasks) {
-		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, true, logFile, log, 0, ret, usedTasks);
-		ForkJoinPool pool = new ForkJoinPool();
-		pool.invoke(unifyTask);
-		Set<Set<UnifyPair>> res =  unifyTask.join();
-		try {
-			logFile.write("\nnoShortendElements: " + unifyTask.noShortendElements +"\n");
-			logFile.flush();
-		}
-		catch (IOException e) {
-			System.err.println("no log-File");
-		}
-		return ret;
+	public static Set<Set<UnifyPair>> unifyParallel(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, UnifyContext unifyContext) {
+		ForkJoinPool pool = TypeUnify.createThreadPool(unifyContext.logger());
+		UnifyContext context = unifyContext.newWithParallel(true).newWithExecutor(pool);
+		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, context, 0);
+		var result = joinFuture(unifyTask.compute());
+
+		unifyContext.logger().debug("\nnoShortendElements: " + TypeUnifyTask.noShortendElements + "\n");
+		return result;
 	}
 	
 	/*
@@ -97,25 +72,22 @@ public class TypeUnify {
 	
 	/**
 	 * unify sequentiell mit oderconstraints
-	 * @param undConstrains
-	 * @param oderConstraints
-	 * @param fc
-	 * @param logFile
-	 * @param log
-	 * @param cons
-	 * @return
 	 */
-	public Set<Set<UnifyPair>> unifyOderConstraints(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, Writer logFile, Boolean log, UnifyResultModel ret, UnifyTaskModel usedTasks) {
-		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, false, logFile, log, 0, ret, usedTasks);
-		Set<Set<UnifyPair>> res = unifyTask.compute();
-		try {
-			logFile.write("\nnoShortendElements: " + unifyTask.noShortendElements +"\n");
-			logFile.flush();
-		}
-		catch (IOException e) {
-			System.err.println("no log-File");
-		}
+	public static Set<Set<UnifyPair>> unifyOderConstraints(Set<UnifyPair> undConstrains, List<Set<Constraint<UnifyPair>>> oderConstraints, IFiniteClosure fc, UnifyContext unifyContext) {
+		TypeUnifyTask unifyTask = new TypeUnifyTask(undConstrains, oderConstraints, fc, unifyContext.newWithParallel(false), 0);
+		Set<Set<UnifyPair>> res = joinFuture(unifyTask.compute());
+		unifyContext.logger().debug("\nnoShortendElements: " + TypeUnifyTask.noShortendElements +"\n");
 		return res;
 	}
 
+	private static ForkJoinPool createThreadPool(Logger logger) {
+		logger.info("Available processors: " + Runtime.getRuntime().availableProcessors());
+		return new ForkJoinPool(
+			Runtime.getRuntime().availableProcessors(),
+			ForkJoinPool.defaultForkJoinWorkerThreadFactory,
+			null,
+			false
+		);
+	}
+
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnify2Task.java

@@ -13,54 +13,46 @@ import de.dhbwstuttgart.typeinference.constraints.ConstraintSet;
 import de.dhbwstuttgart.typeinference.constraints.Pair;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import java.util.concurrent.CompletableFuture;
 
 public class TypeUnify2Task extends TypeUnifyTask {
-       
-       Set<Set<UnifyPair>> setToFlatten;
-       Set<UnifyPair> methodSignatureConstraintUebergabe;
 
-       public TypeUnify2Task(Set<Set<UnifyPair>> setToFlatten, Set<UnifyPair> eq, List<Set<Constraint<UnifyPair>>> oderConstraints, Set<UnifyPair> nextSetElement, IFiniteClosure fc, boolean parallel, Writer logFile, Boolean log, int rekTiefe, UnifyResultModel urm, UnifyTaskModel usedTasks, Set<UnifyPair> methodSignatureConstraintUebergabe) {
-               super(eq, oderConstraints, fc, parallel, logFile, log, rekTiefe, urm, usedTasks);
-               this.setToFlatten = setToFlatten;
-               this.nextSetElement = nextSetElement;
-               this.methodSignatureConstraintUebergabe = methodSignatureConstraintUebergabe;
-       }
-       
-       Set<UnifyPair> getNextSetElement() {
-    	   return nextSetElement;
-       }
-       
-       @Override
-       protected Set<Set<UnifyPair>> compute() {
-               if (one) {
-                       System.out.println("two");
-               }
-               one = true;
-               Set<Set<UnifyPair>> res = unify2(setToFlatten, eq, oderConstraintsField, fc, parallel, rekTiefeField, methodSignatureConstraintUebergabe);
+  Set<Set<UnifyPair>> setToFlatten;
+  Set<UnifyPair> methodSignatureConstraintUebergabe;
+
+  public TypeUnify2Task(Set<Set<UnifyPair>> setToFlatten, Set<UnifyPair> eq, List<Set<Constraint<UnifyPair>>> oderConstraints, Set<UnifyPair> nextSetElement, IFiniteClosure fc, UnifyContext context, int rekTiefe, Set<UnifyPair> methodSignatureConstraintUebergabe) {
+    super(eq, oderConstraints, fc, context, rekTiefe);
+    this.setToFlatten = setToFlatten;
+    this.nextSetElement = nextSetElement;
+    this.methodSignatureConstraintUebergabe = methodSignatureConstraintUebergabe;
+  }
+
+  public Set<UnifyPair> getNextSetElement() {
+    return nextSetElement;
+  }
+
+  @Override
+  public CompletableFuture<Set<Set<UnifyPair>>> compute() {
+    if (one) {
+      context.logger().info("two");
+    }
+    one = true;
+    CompletableFuture<Set<Set<UnifyPair>>> res =
+      unify2(setToFlatten, eq, oderConstraintsField, fc, context.parallel(), rekTiefeField, methodSignatureConstraintUebergabe);
                /*if (isUndefinedPairSetSet(res)) { 
                        return new HashSet<>(); }
                else
-               */ 
-               //writeLog("xxx");
-               //noOfThread--;
-               synchronized (usedTasks) {
-            	   if (this.myIsCancelled()) {
-   						return new HashSet<>();
-   					}
-   					else {
-   						return res;
-   					}
-   				}
-       	}
-       
-       public void closeLogFile() {
+               */
+    //writeLog("xxx");
+    //noOfThread--;
+    if (this.isExecutionCancelled()) {
+      return CompletableFuture.completedFuture(new HashSet<>());
+    } else {
+      return res;
+    }
+  }
 
-           try {
-				logFile.close();
-			}
-			catch (IOException ioE) {
-				System.err.println("no log-File" + thNo);
-			}
-           
-       }
+  public void closeLogFile() {
+    context.logger().close();
+  }
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/TypeUnifyTaskHelper.java

@@ -0,0 +1,221 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import de.dhbwstuttgart.typeinference.unify.model.PairOperator;
+import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyType;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+/**
+ * A collection of capsuled (and thus static) functions to split up large algorithms in TypeUnifyTask
+ */
+public class TypeUnifyTaskHelper {
+
+  /**
+   * Filter all topLevelSets for those with a single element that contain only one pair:
+   *   a <. theta,
+   *   theta <. a or
+   *   a =. theta
+   */
+  public static Set<Set<UnifyPair>> getSingleElementSets(ArrayList<Set<? extends Set<UnifyPair>>> topLevelSets) {
+    return topLevelSets.stream()
+      .filter(x -> x.size() == 1)
+      .map(y -> y.stream().findFirst().get()).collect(Collectors.toSet());
+  }
+
+  /**
+   * Varianzbestimmung Anfang
+   * Oderconstraint, wenn entweder kein Basepair oder unterschiedliche Basepairs => oderConstraint = true;
+   * Varianz =  1 => Argumentvariable
+   * Varianz = -1 => Rückgabevariable
+   * Varianz =  0 => unklar
+   * Varianz =  2 => Operatoren oderConstraints
+   */
+  public static int calculateVariance(List<Set<UnifyPair>> nextSetasList) {
+    Optional<Integer> xi = nextSetasList.stream().map(x -> x.stream().filter(y -> (y.getLhsType() instanceof PlaceholderType && !(y.getRhsType() instanceof PlaceholderType)))
+        .filter(z -> ((PlaceholderType) z.getLhsType()).getVariance() != 0)
+        .map(c -> ((PlaceholderType) c.getLhsType()).getVariance())
+        .reduce((a, b) -> {
+          if (a.intValue() == b.intValue()) return a;
+          else return 0;
+        })) //2 kommt insbesondere bei Oder-Constraints vor
+      .filter(Optional::isPresent)
+      .map(Optional::get)
+      .findAny();
+
+    return xi.orElse(0);
+  }
+
+  /**
+   *
+   */
+  public static int calculateOderConstraintVariance(List<Set<UnifyPair>> nextSetAsList) {
+    Optional<Integer> optVariance =
+      nextSetAsList
+        .getFirst()
+        .stream()
+        .filter(x -> x.getGroundBasePair().getLhsType() instanceof PlaceholderType &&
+          !(x.getRhsType() instanceof PlaceholderType) &&
+          x.getPairOp() == PairOperator.EQUALSDOT)
+        .map(x ->
+          ((PlaceholderType) x.getGroundBasePair().getLhsType()).getVariance())
+        .reduce((n, m) -> (n != 0) ? n : m);
+
+    //Fuer Operatorenaufrufe wird variance auf 2 gesetzt.
+    //da kein Receiver existiert also kein x.getGroundBasePair().getLhsType() instanceof PlaceholderType
+    //Bei Varianz = 2 werden alle Elemente des Kartesischen Produkts abgearbeitet
+    return optVariance.orElse(2);
+  }
+
+
+  /**
+   * Find the first occurrence (if any) of a UnifyPair with operator EQUALSDOT while having
+   * one side equal to its base pair counterpart
+   */
+  public static Optional<UnifyPair> findEqualityConstrainedUnifyPair(Set<UnifyPair> nextSetElement) {
+    return nextSetElement.stream().filter(x ->
+        x.getPairOp()
+        .equals(PairOperator.EQUALSDOT))
+      .filter(x -> //Sicherstellen, dass bei a = ty a auch wirklich die gesuchte Typvariable ist
+        x.getLhsType()
+          .equals(x.getBasePair().getLhsType()) ||
+        x.getLhsType()
+          .equals(x.getBasePair().getRhsType())
+    ).findFirst();
+  }
+
+  /**
+   *  Find all unifyPairs, that associate the identified type variable of origPair with any concrete type. That means:
+   *  If "a = type" is in origPair, then we get all UnifyPairs that contain either "a < typeA" or "typeB < a"
+   */
+  public static Set<UnifyPair> findConstraintsWithSameTVAssociation(UnifyPair origPair, Set<Set<UnifyPair>> singleElementSets) {
+    UnifyType tyVar = origPair.getLhsType();
+    if (!(tyVar instanceof PlaceholderType)) {
+      tyVar = origPair.getRhsType();
+    }
+
+    UnifyType tyVarEF = tyVar;
+    return singleElementSets.stream()
+      .map(xx ->
+        xx.iterator().next())
+      .filter(x ->
+            (x.getLhsType().equals(tyVarEF) && !(x.getRhsType() instanceof PlaceholderType))
+            ||
+            (x.getRhsType().equals(tyVarEF) && !(x.getLhsType() instanceof PlaceholderType))
+      )
+      .collect(Collectors.toCollection(HashSet::new));
+  }
+
+  /**
+   *
+   */
+  public static boolean doesFirstNextSetHasSameBase(List<Set<UnifyPair>> nextSetAsList) {
+    if (nextSetAsList.isEmpty()) {
+      return false;
+    }
+
+    UnifyPair firstBasePair = null;
+
+    for (var unifyPair : nextSetAsList.getFirst().stream().toList()) {
+      var basePair = unifyPair.getBasePair();
+
+      // if any base pair is null, there is NOT always the same base!
+      if (basePair == null) {
+        return false;
+      }
+
+      if (firstBasePair == null) {
+        firstBasePair = basePair;
+      }
+      else if (!basePair.equals(firstBasePair)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  /**
+   *  Extracts data from every element in the nested lists of results. What data depends on the given
+   *  extractor function
+   */
+  public static Set<UnifyPair> collectFromThreadResult (
+    Set<Set<UnifyPair>> currentThreadResult,
+    Function<UnifyPair, Set<UnifyPair>> extractor
+  ) {
+    return currentThreadResult.stream()
+      .map(b ->
+        b.stream()
+          .map(extractor)
+          .reduce((y, z) -> {
+            y.addAll(z);
+            return y;
+          })
+          .orElse(new HashSet<>()))
+      .reduce((y, z) -> {
+        y.addAll(z);
+        return y;
+      })
+      .orElse(new HashSet<>());
+  }
+
+  /**
+   *  Extract a list of PlaceholderTypes from a set of pairs, such that each resulting element:
+   *  - Is the LHS of a pair
+   *  - Is a PlaceholderType
+   *  - has a basePair Side that is a PlaceholderType with the same name
+   */
+  public static List<PlaceholderType> extractMatchingPlaceholderTypes(Set<UnifyPair> pairs) {
+    return pairs.stream()
+      .filter(x -> {
+        UnifyType lhs = x.getLhsType();
+        UnifyType baseLhs = x.getBasePair().getLhsType();
+        UnifyType baseRhs = x.getBasePair().getRhsType();
+        return (lhs instanceof PlaceholderType) &&
+          ((baseLhs instanceof PlaceholderType && lhs.getName().equals(baseLhs.getName())) ||
+            (baseRhs instanceof PlaceholderType && lhs.getName().equals(baseRhs.getName())));
+      })
+      .map(x -> (PlaceholderType) x.getLhsType())
+      .collect(Collectors.toCollection(ArrayList::new));
+  }
+
+
+  public static Set<UnifyPair> occursCheck(final Set<UnifyPair> eq) {
+    Set<UnifyPair> ocurrPairs = new HashSet<>(eq.size());
+    for (UnifyPair x : eq) {
+      UnifyType lhs = x.getLhsType();
+      UnifyType rhs = x.getRhsType();
+      if (lhs instanceof PlaceholderType lhsPlaceholder &&
+        !(rhs instanceof PlaceholderType) &&
+        rhs.getTypeParams().occurs(lhsPlaceholder))
+      {
+        x.setUndefinedPair();
+        ocurrPairs.add(x);
+      }
+    }
+    return ocurrPairs;
+  }
+
+
+  public static <T> HashSet<T> getPresizedHashSet(int minElements) {
+    if (minElements < 16) return new HashSet<>();
+    // HashSet and HashMap will resize at 75% load, so we account for that by multiplying with 1.5
+    int n = (int)(minElements * 1.5);
+    return new HashSet<>(n);
+  }
+
+  public static <S,T> HashMap<S,T> getPresizedHashMap(int minElements) {
+    if (minElements < 16) return new HashMap<>();
+    // HashSet and HashMap will resize at 75% load, so we account for that by multiplying with 1.5
+    int n = (int)(minElements * 1.5);
+    return new HashMap<>(n);
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/UnifyContext.java

@@ -0,0 +1,67 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import de.dhbwstuttgart.util.Logger;
+import java.io.Writer;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.ForkJoinPool;
+
+public record UnifyContext(
+  // main logger of a unification
+  Logger logger,
+  // if the unify algorithm should run in parallel
+  boolean parallel,
+  // the model for storing calculated results
+  UnifyResultModel resultModel,
+  // the executor used for thread management in parallel execution
+  ExecutorService executor,
+  // a generator for new placeholders in this unify context
+  PlaceholderRegistry placeholderRegistry,
+  // a control structure to cancel the unification early
+  UnifyTaskModel usedTasks
+) {
+
+  public UnifyContext(
+    Logger logger,
+    boolean parallel,
+    UnifyResultModel resultModel,
+    UnifyTaskModel usedTasks,
+    ExecutorService executor,
+    PlaceholderRegistry placeholderRegistry
+  ) {
+    this(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
+  }
+
+  public UnifyContext(
+    Logger logger,
+    boolean parallel,
+    UnifyResultModel resultModel,
+    UnifyTaskModel usedTasks,
+    PlaceholderRegistry placeholderRegistry
+  ) {
+    this(logger, parallel, resultModel, usedTasks, ForkJoinPool.commonPool(), placeholderRegistry);
+  }
+
+
+  /*
+   * Shortcuts for creating a similar context with some properties changed. This combined with the final properties
+   * causes the UnifyContext to be essentially handled as a
+   */
+
+  public UnifyContext newWithLogger(Logger logger) {
+    return new UnifyContext(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
+  }
+
+  public UnifyContext newWithParallel(boolean parallel) {
+    if (this.parallel == parallel) return this;
+    return new UnifyContext(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
+  }
+
+  public UnifyContext newWithExecutor(ExecutorService executor) {
+    return new UnifyContext(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
+  }
+
+  public UnifyContext newWithResultModel(UnifyResultModel resultModel) {
+    return new UnifyContext(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/UnifyResultModel.java

@@ -36,19 +36,19 @@ public class UnifyResultModel {
 		listeners.remove(listenerToRemove);
 	}
 	
-	public void notify(Set<Set<UnifyPair>> eqPrimePrimeSet) {
+	public void notify(Set<Set<UnifyPair>> eqPrimePrimeSet, UnifyContext context) {
 		Set<Set<UnifyPair>> eqPrimePrimeSetRet = eqPrimePrimeSet.stream().map(x -> {
-			Optional<Set<UnifyPair>> res = new RuleSet().subst(x.stream().map(y -> { 
+			Optional<Set<UnifyPair>> res = new RuleSet(context.placeholderRegistry()).subst(x.stream().map(y -> {
 				if (y.getPairOp() == PairOperator.SMALLERDOTWC) y.setPairOp(PairOperator.EQUALSDOT);
 				return y; //alle Paare a <.? b erden durch a =. b ersetzt
 			}).collect(Collectors.toCollection(HashSet::new)));
 			if (res.isPresent()) {//wenn subst ein Erg liefert wurde was veraendert
-				return new TypeUnifyTask().applyTypeUnificationRules(res.get(), fc);
+				return new TypeUnifyTask(context).applyTypeUnificationRules(res.get(), fc);
 			}
 			else return x; //wenn nichts veraendert wurde wird x zurueckgegeben
 		}).collect(Collectors.toCollection(HashSet::new));
 		List<ResultSet> newResult = eqPrimePrimeSetRet.stream().map(unifyPairs ->
-           new ResultSet(UnifyTypeFactory.convert(unifyPairs, de.dhbwstuttgart.typeinference.constraints.Pair.generateTPHMap(cons))))
+           new ResultSet(UnifyTypeFactory.convert(unifyPairs, de.dhbwstuttgart.typeinference.constraints.Pair.generateTPHMap(cons), context.placeholderRegistry())))
            .collect(Collectors.toList());
 		UnifyResultEvent evt = new UnifyResultEvent(newResult);
 		

src/main/java/de/dhbwstuttgart/typeinference/unify/UnifyTaskModel.java

@@ -12,7 +12,7 @@ public class UnifyTaskModel {
     
     public synchronized void cancel() {
     	for(TypeUnifyTask t : usedTasks) {
-    		t.myCancel(true);
+    		t.cancelExecution();
     	}
     }
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/ContravarianceCase.java

@@ -0,0 +1,209 @@
+package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
+
+import de.dhbwstuttgart.typeinference.constraints.Constraint;
+import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Tuple;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.Collectors;
+
+public class ContravarianceCase extends VarianceCase {
+
+  protected final int variance = 1;
+
+  protected ContravarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    super(isOderConstraint, typeUnifyTask, context);
+  }
+
+  @Override
+  public void selectNextData(
+    TypeUnifyTask typeUnifyTask,
+    List<Set<UnifyPair>> nextSetAsList,
+    Optional<UnifyPair> optOrigPair
+  ) {
+    a = typeUnifyTask.oup.max(nextSetAsList.iterator());
+    context.logger().debug("Max: a in " + variance + " " + a);
+    nextSetAsList.remove(a);
+    if (this.isOderConstraint) {
+      nextSetasListOderConstraints.add(((Constraint<UnifyPair>) a).getExtendConstraint());
+    }
+    context.logger().debug(() -> "nextSetasListOderConstraints 1: " + nextSetasListOderConstraints);
+
+    //Alle maximale Elemente in nextSetasListRest bestimmen
+    //nur für diese wird parallele Berechnung angestossen.
+    Set<UnifyPair> finalA = a;
+    nextSetasListRest = typeUnifyTask.oup.maxElements(
+      nextSetAsList.stream().filter(a_next -> typeUnifyTask.oup.compare(finalA, a_next) != 1).toList()
+    );
+  }
+
+
+  @Override
+  public CompletableFuture<ComputationResults> computeParallel(
+    Set<Set<UnifyPair>> elems,
+    Set<UnifyPair> eq,
+    List<Set<Constraint<UnifyPair>>> oderConstraints,
+    IFiniteClosure fc,
+    int rekTiefe,
+    Set<UnifyPair> methodSignatureConstraint,
+    List<Set<UnifyPair>> nextSetAsList,
+    Set<UnifyPair> sameEqSet,
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> aParDef
+  ) {
+    Set<UnifyPair> newEqOrig = new HashSet<>(eq);
+    Set<Set<UnifyPair>> newElemsOrig = new HashSet<>(elems);
+    List<Set<Constraint<UnifyPair>>> newOderConstraintsOrig = new ArrayList<>(oderConstraints);
+    newElemsOrig.add(a);
+
+    /* FORK ANFANG */
+    TypeUnify2Task forkOrig = new TypeUnify2Task(newElemsOrig, newEqOrig, newOderConstraintsOrig, a, fc, context, rekTiefe, methodSignatureConstraint);
+    typeUnifyTask.addChildTask(forkOrig);
+    // schedule compute() on another thread
+    CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply(
+      (currentThreadResult) -> {
+        forkOrig.context.logger().debug("final Orig 1");
+        forkOrig.closeLogFile();
+        return new ComputationResults(currentThreadResult);
+      });
+
+    //forks.add(forkOrig);
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return CompletableFuture.completedFuture(new ComputationResults());
+    }
+    /* FORK ENDE */
+
+    context.logger().debug("a in " + variance + " " + a);
+    context.logger().debug("nextSetasListRest: " + nextSetasListRest.toString());
+    while (!nextSetasListRest.isEmpty()) {
+      Set<UnifyPair> nSaL = nextSetasListRest.removeFirst();
+      nextSetAsList.remove(nSaL);
+      context.logger().debug("1 RM" + nSaL.toString());
+
+      if (!this.isOderConstraint) {
+        //ueberpruefung ob zu a =. ty \in nSaL in sameEqSet ein Widerspruch besteht
+        if (!sameEqSet.isEmpty() && !typeUnifyTask.checkNoContradiction(nSaL, sameEqSet, result)) {
+          TypeUnifyTask.noShortendElements++;
+          continue;
+        }
+      } else {
+        nextSetasListOderConstraints.add(((Constraint<UnifyPair>) nSaL).getExtendConstraint());
+      }
+      Set<UnifyPair> newEq = new HashSet<>(eq);
+      Set<Set<UnifyPair>> newElems = new HashSet<>(elems);
+      List<Set<Constraint<UnifyPair>>> newOderConstraints = new ArrayList<>(oderConstraints);
+      newElems.add(nSaL);
+      TypeUnify2Task fork = new TypeUnify2Task(newElems, newEq, newOderConstraints, nSaL, fc, context, rekTiefe, new HashSet<>(methodSignatureConstraint));
+      typeUnifyTask.addChildTask(fork);
+      // schedule compute() on another thread
+      CompletableFuture<Set<Set<UnifyPair>>> forkFuture = CompletableFuture.supplyAsync(fork::compute, context.executor()).thenCompose(f -> f);
+      resultValues = resultValues.thenCombine(forkFuture,
+        (prevResults, fork_res) -> {
+          if (typeUnifyTask.isExecutionCancelled()) {
+            return new ComputationResults();
+          }
+          context.logger().debug("fork_res: " + fork_res.toString());
+          context.logger().debug(Boolean.valueOf((typeUnifyTask.isUndefinedPairSetSet(fork_res))).toString());
+          prevResults.addForkResult(fork_res);
+          if (!typeUnifyTask.isUndefinedPairSetSet(fork_res)) {
+            aParDef.add(fork.getNextSetElement());
+          }
+          fork.context.logger().debug("final 1");
+          fork.closeLogFile();
+        return prevResults;
+        }
+      );
+
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return CompletableFuture.completedFuture(new ComputationResults());
+      }
+    }
+
+    return resultValues;
+  }
+
+  @Override
+  public void applyComputedResults(
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> currentThreadResult,
+    Set<UnifyPair> compResult,
+    Set<UnifyPair> compRes
+  ) {
+    int resOfCompare = typeUnifyTask.oup.compare(compResult, compRes);
+    if (resOfCompare == -1) {
+      context.logger().debug("Geloescht result: " + result);
+      result.clear();
+      result.addAll(currentThreadResult);
+    }
+    else if (resOfCompare == 0) {
+      result.addAll(currentThreadResult);
+    }
+    else if (resOfCompare == 1) {
+      context.logger().debug("Geloescht currentThreadResult: " + currentThreadResult);
+      //result = result;
+    }
+  }
+
+  @Override
+  public boolean eraseInvalidSets(
+    int rekTiefe,
+    Set<Set<UnifyPair>> aParDef,
+    List<Set<UnifyPair>> nextSetAsList
+  ) {
+    // context.logger().info("");
+    context.logger().debug("a: " + rekTiefe + " variance: " + variance + a.toString());
+    context.logger().debug("aParDef: " + aParDef.toString());
+    aParDef.add(a);
+    Iterator<Set<UnifyPair>> aParDefIt = aParDef.iterator();
+    if (this.isOderConstraint) {
+      nextSetAsList.removeAll(nextSetasListOderConstraints);
+      nextSetasListOderConstraints = new ArrayList<>();
+      context.logger().debug("Removed: " + nextSetasListOderConstraints);
+      while (aParDefIt.hasNext()) {
+        Set<UnifyPair> a_new = aParDefIt.next();
+        List<Set<UnifyPair>> smallerSetasList = typeUnifyTask.oup.smallerThan(a_new, nextSetAsList);
+        context.logger().debug("smallerSetasList: " + smallerSetasList);
+        List<Set<UnifyPair>> notInherited = smallerSetasList.stream()
+          .filter(x -> !((Constraint<UnifyPair>) x).isInherited() && !((Constraint<UnifyPair>) x).isImplemented())
+          .collect(Collectors.toCollection(ArrayList::new));
+        context.logger().debug("notInherited: " + notInherited + "\n");
+        List<Set<UnifyPair>> notErased = new ArrayList<>();
+        notInherited.forEach(x -> {
+          notErased.addAll(typeUnifyTask.oup.smallerEqThan(x, smallerSetasList));
+        });
+        List<Set<UnifyPair>> erased = new ArrayList<>(smallerSetasList);
+        context.logger().debug("notErased: " + notErased + "\n");
+        erased.removeAll(notErased);
+        nextSetAsList.removeAll(erased);
+
+        context.logger().debug("Removed: " + erased);
+
+        context.logger().debug("Not Removed: " + nextSetAsList);
+
+      }
+    } else {
+      while (aParDefIt.hasNext()) {
+        //nextSetasListIt = nextSetasList.iterator(); Sollte eingefuegt werden PL 2020-04-28
+        Set<UnifyPair> a_new = aParDefIt.next();
+        List<Set<UnifyPair>> erased = typeUnifyTask.oup.smallerEqThan(a_new, nextSetAsList);
+        nextSetAsList.removeAll(erased);
+
+        context.logger().debug("Removed: " + erased);
+
+        context.logger().debug("Not Removed: " + nextSetAsList);
+      }
+    }
+
+    return false;
+  }
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/CovarianceCase.java

@@ -0,0 +1,226 @@
+package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
+
+import de.dhbwstuttgart.typeinference.constraints.Constraint;
+import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Tuple;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.Collectors;
+
+public class CovarianceCase extends VarianceCase {
+
+  protected final int variance = -1;
+
+  protected CovarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    super(isOderConstraint, typeUnifyTask, context);
+  }
+
+  @Override
+  public void selectNextData(
+    TypeUnifyTask typeUnifyTask,
+    List<Set<UnifyPair>> nextSetAsList,
+    Optional<UnifyPair> optOrigPair
+  ) {
+    a = typeUnifyTask.oup.min(nextSetAsList.iterator());
+    context.logger().debug(() -> "Min: a in " + variance + " " + a);
+    if (this.isOderConstraint) {
+      nextSetasListOderConstraints.add(((Constraint<UnifyPair>) a).getExtendConstraint());
+    }
+    context.logger().debug(() -> "nextSetasListOderConstraints -1: " + nextSetasListOderConstraints);
+    nextSetAsList.remove(a);
+
+    //Alle minimalen Elemente in nextSetasListRest bestimmen
+    //nur für diese wird parallele Berechnung angestossen.
+    Set<UnifyPair> finalA = a;
+    nextSetasListRest = typeUnifyTask.oup.minElements(
+      nextSetAsList.stream().filter(a_next -> typeUnifyTask.oup.compare(finalA, a_next) != -1).toList()
+    );
+  }
+
+
+  @Override
+  public CompletableFuture<ComputationResults> computeParallel(
+    Set<Set<UnifyPair>> elems,
+    Set<UnifyPair> eq,
+    List<Set<Constraint<UnifyPair>>> oderConstraints,
+    IFiniteClosure fc,
+    int rekTiefe,
+    Set<UnifyPair> methodSignatureConstraint,
+    List<Set<UnifyPair>> nextSetAsList,
+    Set<UnifyPair> sameEqSet,
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> aParDef
+  ) {
+    Set<UnifyPair> newEqOrig = new HashSet<>(eq);
+    Set<Set<UnifyPair>> newElemsOrig = new HashSet<>(elems);
+    List<Set<Constraint<UnifyPair>>> newOderConstraintsOrig = new ArrayList<>(oderConstraints);
+    newElemsOrig.add(a);
+
+    /* FORK ANFANG */
+    TypeUnify2Task forkOrig = new TypeUnify2Task(newElemsOrig, newEqOrig, newOderConstraintsOrig, a, fc, context, rekTiefe, methodSignatureConstraint);
+    typeUnifyTask.addChildTask(forkOrig);
+    // schedule compute() on another thread
+    CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply(
+      (currentThreadResult) -> {
+        forkOrig.context.logger().debug("final Orig -1");
+        forkOrig.closeLogFile();
+        return new ComputationResults(currentThreadResult);
+      });
+
+    //forks.add(forkOrig);
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return resultValues;
+    }
+    /* FORK ENDE */
+
+    context.logger().debug(() -> "a in " + variance + " " + a);
+    context.logger().debug(() -> "nextSetasListRest: " + nextSetasListRest.toString());
+
+    while (!nextSetasListRest.isEmpty()) {
+      Set<UnifyPair> nSaL = nextSetasListRest.removeFirst();
+      nextSetAsList.remove(nSaL);
+      context.logger().debug(() -> "-1 RM" + nSaL.toString());
+
+      if (!this.isOderConstraint) {
+        //ueberpruefung ob zu a =. ty \in nSaL in sameEqSet ein Widerspruch besteht
+        if (!sameEqSet.isEmpty() && !typeUnifyTask.checkNoContradiction(nSaL, sameEqSet, result)) {
+          TypeUnifyTask.noShortendElements++;
+          continue;
+        }
+      } else {
+        nextSetasListOderConstraints.add(((Constraint<UnifyPair>) nSaL).getExtendConstraint());
+      }
+      Set<UnifyPair> newEq = new HashSet<>(eq);
+      Set<Set<UnifyPair>> newElems = new HashSet<>(elems);
+      List<Set<Constraint<UnifyPair>>> newOderConstraints = new ArrayList<>(oderConstraints);
+      newElems.add(nSaL);
+      TypeUnify2Task fork = new TypeUnify2Task(newElems, newEq, newOderConstraints, nSaL, fc, context, rekTiefe, new HashSet<>(methodSignatureConstraint));
+      typeUnifyTask.addChildTask(fork);
+      // schedule compute() on another thread
+      CompletableFuture<Set<Set<UnifyPair>>> forkFuture = CompletableFuture.supplyAsync(fork::compute, context.executor()).thenCompose(f -> f);
+      resultValues = resultValues.thenCombine(forkFuture,
+        (prevResults, fork_res) -> {
+          if (typeUnifyTask.isExecutionCancelled()) {
+            return prevResults;
+          }
+          context.logger().debug(() -> "fork_res: " + fork_res.toString());
+          context.logger().debug(() -> Boolean.valueOf((typeUnifyTask.isUndefinedPairSetSet(fork_res))).toString());
+          prevResults.addForkResult(fork_res);
+          if (!typeUnifyTask.isUndefinedPairSetSet(fork_res)) {
+            aParDef.add(fork.getNextSetElement());
+          }
+          fork.context.logger().debug("final -1");
+          fork.closeLogFile();
+        return prevResults;
+        }
+      );
+
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return resultValues;
+      }
+    }
+
+    return resultValues;
+  }
+
+
+  @Override
+  public void applyComputedResults(
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> currentThreadResult,
+    Set<UnifyPair> compResult,
+    Set<UnifyPair> compRes
+  ) {
+    int resOfCompare = typeUnifyTask.oup.compare(compResult, compRes);
+    if (resOfCompare == 1) {
+      context.logger().debug(() -> "Geloescht result: " + result);
+      result.clear();
+      result.addAll(currentThreadResult);
+    } else if (resOfCompare == 0) {
+      result.addAll(currentThreadResult);
+    } else if (resOfCompare == -1) {
+      context.logger().debug(() -> "Geloescht currentThreadResult: " + currentThreadResult);
+      //result = result;
+    }
+  }
+
+  @Override
+  public boolean eraseInvalidSets(
+    int rekTiefe,
+    Set<Set<UnifyPair>> aParDef,
+    List<Set<UnifyPair>> nextSetAsList
+  ) {
+
+    // context.logger().info("");
+    context.logger().debug(() -> "a: " + rekTiefe + " variance: " + variance + a.toString());
+    context.logger().debug(() -> "aParDef: " + aParDef.toString());
+    aParDef.add(a);
+    Iterator<Set<UnifyPair>> aParDefIt = aParDef.iterator();
+    if (this.isOderConstraint) {
+      nextSetAsList.removeAll(nextSetasListOderConstraints);
+      context.logger().debug(() -> "Removed: " + nextSetasListOderConstraints);
+      nextSetasListOderConstraints = new ArrayList<>();
+      while (aParDefIt.hasNext()) {
+        Set<UnifyPair> a_new = aParDefIt.next();
+        List<Set<UnifyPair>> greaterSetasList = typeUnifyTask.oup.greaterThan(a_new, nextSetAsList);
+
+        //a_new muss hingefuegt werden, wenn es nicht vererbt ist, dann wird es spaeter wieder geloescht
+        if (!((Constraint<UnifyPair>) a_new).isInherited()) {
+          greaterSetasList.add(a_new);
+        }
+        List<Set<UnifyPair>> notInherited = greaterSetasList.stream()
+          .filter(x -> !((Constraint<UnifyPair>) x).isInherited())
+          .collect(Collectors.toCollection(ArrayList::new));
+        List<Set<UnifyPair>> notErased = new ArrayList<>();
+
+        //Wenn x nicht vererbt ist, beginnt beim naechstgroesseren Element die naechste Ueberladung
+        notInherited.forEach(x -> {
+          notErased.addAll(typeUnifyTask.oup.greaterEqThan(x, greaterSetasList));
+        });
+
+        //das kleineste Element ist das Element von dem a_new geerbt hat
+        //muss deshalb geloescht werden
+        Iterator<Set<UnifyPair>> notErasedIt = notErased.iterator();
+        if (notErasedIt.hasNext()) {
+          Set<UnifyPair> min = typeUnifyTask.oup.min(notErasedIt);
+          notErased.remove(min);
+          notErased.remove(((Constraint<UnifyPair>) min).getExtendConstraint());
+        }
+
+        List<Set<UnifyPair>> erased = new ArrayList<>(greaterSetasList);
+        erased.removeAll(notErased);
+        nextSetAsList.removeAll(erased);
+
+        context.logger().debug(() -> "Removed: " + erased);
+
+        context.logger().debug(() -> "Not Removed: " + nextSetAsList);
+
+      }
+    } else {
+      while (aParDefIt.hasNext()) {
+        //nextSetasListIt = nextSetasList.iterator(); Sollte eingefuegt werden PL 2020-04-28
+        Set<UnifyPair> a_new = aParDefIt.next();
+        List<Set<UnifyPair>> erased = typeUnifyTask.oup.greaterEqThan(a_new, nextSetAsList);
+
+        nextSetAsList.removeAll(erased);
+
+        context.logger().debug(() -> "Removed: " + erased);
+
+        context.logger().debug(() -> "Not Removed: " + nextSetAsList);
+      }
+    }
+
+    return false;
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/InvarianceOrConstraintCase.java

@@ -0,0 +1,132 @@
+package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
+
+import de.dhbwstuttgart.typeinference.constraints.Constraint;
+import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Tuple;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+
+public class InvarianceOrConstraintCase extends VarianceCase {
+
+  // either for invariance or for oderConstraints
+  protected final int variance = 2;
+
+  protected InvarianceOrConstraintCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    super(isOderConstraint, typeUnifyTask, context);
+  }
+
+  @Override
+  public void selectNextData(
+    TypeUnifyTask typeUnifyTask,
+    List<Set<UnifyPair>> nextSetAsList,
+    Optional<UnifyPair> optOrigPair
+
+  ) {
+    a = nextSetAsList.removeFirst();
+    //Fuer alle Elemente wird parallele Berechnung angestossen.
+    nextSetasListRest = new ArrayList<>(nextSetAsList);
+  }
+
+
+  @Override
+  public CompletableFuture<ComputationResults> computeParallel(
+    Set<Set<UnifyPair>> elems,
+    Set<UnifyPair> eq,
+    List<Set<Constraint<UnifyPair>>> oderConstraints,
+    IFiniteClosure fc,
+    int rekTiefe,
+    Set<UnifyPair> methodSignatureConstraint,
+    List<Set<UnifyPair>> nextSetAsList,
+    Set<UnifyPair> sameEqSet,
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> aParDef
+  ) {
+    context.logger().debug("var2einstieg");
+    Set<TypeUnify2Task> forks = new HashSet<>();
+    Set<UnifyPair> newEqOrig = new HashSet<>(eq);
+    Set<Set<UnifyPair>> newElemsOrig = new HashSet<>(elems);
+    List<Set<Constraint<UnifyPair>>> newOderConstraintsOrig = new ArrayList<>(oderConstraints);
+    newElemsOrig.add(a);
+
+    /* FORK ANFANG */
+    TypeUnify2Task forkOrig = new TypeUnify2Task(newElemsOrig, newEqOrig, newOderConstraintsOrig, a, fc, context, rekTiefe, new HashSet<>(methodSignatureConstraint));
+    typeUnifyTask.addChildTask(forkOrig);
+    CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply((currentThreadResult) -> {
+      forkOrig.context.logger().debug("final Orig 2");
+      forkOrig.closeLogFile();
+      return new ComputationResults(currentThreadResult);
+    });
+
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return resultValues;
+    }
+    /* FORK ENDE */
+
+    context.logger().debug(() -> "a in " + variance + " " + a);
+    context.logger().debug(() -> "nextSetasListRest: " + nextSetasListRest.toString());
+
+    //Fuer parallele Berechnung der Oder-Contraints wird methodSignature kopiert
+    //und jeweils die methodSignature von a bzw. nSaL wieder gelöscht, wenn es keine Lösung ist.
+    Set<UnifyPair> methodSignatureConstraintForParallel = new HashSet<>(methodSignatureConstraint);
+    Set<UnifyPair> nSaL = a;
+
+    while (!nextSetasListRest.isEmpty()) {
+      methodSignatureConstraintForParallel.removeAll(((Constraint<UnifyPair>) nSaL).getmethodSignatureConstraint());
+      nSaL = nextSetasListRest.removeFirst();
+      nextSetAsList.remove(nSaL); //PL einkommentiert 20-02-03
+      methodSignatureConstraintForParallel.addAll(((Constraint<UnifyPair>) nSaL).getmethodSignatureConstraint());
+      Set<UnifyPair> newEq = new HashSet<>(eq);
+      Set<Set<UnifyPair>> newElems = new HashSet<>(elems);
+      List<Set<Constraint<UnifyPair>>> newOderConstraints = new ArrayList<>(oderConstraints);
+      newElems.add(nSaL);
+      TypeUnify2Task fork = new TypeUnify2Task(newElems, newEq, newOderConstraints, nSaL, fc, context, rekTiefe, new HashSet<>(methodSignatureConstraintForParallel));
+      typeUnifyTask.addChildTask(fork);
+      CompletableFuture<Set<Set<UnifyPair>>> forkFuture = CompletableFuture.supplyAsync(fork::compute, context.executor()).thenCompose(f -> f);
+      resultValues = resultValues.thenCombine(forkFuture, (prevResults, fork_res) -> {
+        if (typeUnifyTask.isExecutionCancelled()) {
+          return prevResults;
+        }
+        prevResults.addForkResult(fork_res);
+        fork.context.logger().debug("final 2");
+        fork.closeLogFile();
+        return prevResults;
+      });
+
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return resultValues;
+      }
+    }
+
+    return resultValues;
+  }
+
+  @Override
+  public void applyComputedResults(
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> currentThreadResult,
+    Set<UnifyPair> compResult,
+    Set<UnifyPair> compRes
+  ) {
+    // Nothing
+  }
+
+  @Override
+  public boolean eraseInvalidSets(
+    int rekTiefe,
+    Set<Set<UnifyPair>> aParDef,
+    List<Set<UnifyPair>> nextSetAsList
+  ) {
+    // Nothing
+    return false;
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/UnknownVarianceCase.java

@@ -0,0 +1,110 @@
+package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
+
+import de.dhbwstuttgart.typeinference.constraints.Constraint;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.PlaceholderType;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Tuple;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.Collectors;
+
+public class UnknownVarianceCase extends VarianceCase {
+
+  protected final int variance = 0;
+
+  protected UnknownVarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    super(isOderConstraint, typeUnifyTask, context);
+  }
+
+  @Override
+  public void selectNextData(
+    TypeUnifyTask typeUnifyTask,
+    List<Set<UnifyPair>> nextSetAsList,
+    Optional<UnifyPair> optOrigPair
+
+  ) {
+    //wenn a <. theta dann ist ein maximales Element sehr wahrscheinlich
+    //wenn theta <. a dann ist ein minimales Element sehr wahrscheinlich
+    if (!this.isOderConstraint && optOrigPair != null && optOrigPair.isPresent()) {
+      if (optOrigPair.get().getBasePair().getLhsType() instanceof PlaceholderType) {
+        a = typeUnifyTask.oup.max(nextSetAsList.iterator());
+      } else {
+        a = typeUnifyTask.oup.min(nextSetAsList.iterator());
+      }
+      nextSetAsList.remove(a);
+    } else if (this.isOderConstraint) {
+      a = typeUnifyTask.oup.max(nextSetAsList.iterator());
+      nextSetAsList.remove(a);
+      nextSetasListOderConstraints.add(((Constraint<UnifyPair>) a).getExtendConstraint());
+    } else {
+      a = nextSetAsList.removeFirst();
+    }
+  }
+
+  @Override
+  public CompletableFuture<ComputationResults> computeParallel(
+    Set<Set<UnifyPair>> elems,
+    Set<UnifyPair> eq,
+    List<Set<Constraint<UnifyPair>>> oderConstraints,
+    IFiniteClosure fc,
+    int rekTiefe,
+    Set<UnifyPair> methodSignatureConstraint,
+    List<Set<UnifyPair>> nextSetAsList,
+    Set<UnifyPair> sameEqSet,
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> aParDef
+  ) {
+    elems.add(a);
+    return typeUnifyTask.unify2(elems, eq, oderConstraints, fc, context.parallel(), rekTiefe, new HashSet<>(methodSignatureConstraint))
+      .thenApply(ComputationResults::new);
+  }
+
+  @Override
+  public void applyComputedResults(
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> currentThreadResult,
+    Set<UnifyPair> compResult,
+    Set<UnifyPair> compRes
+  ) {
+    context.logger().debug("RES var=0 ADD:" + result.toString() + " " + currentThreadResult.toString());
+    result.addAll(currentThreadResult);
+  }
+
+  @Override
+  public boolean eraseInvalidSets(
+    int rekTiefe,
+    Set<Set<UnifyPair>> aParDef,
+    List<Set<UnifyPair>> nextSetAsList
+  ) {
+    if (!this.isOderConstraint) {
+      return true;
+    } else {
+      nextSetAsList.removeAll(nextSetasListOderConstraints);
+      nextSetasListOderConstraints = new ArrayList<>();
+      context.logger().debug("Removed: " + nextSetasListOderConstraints);
+      List<Set<UnifyPair>> smallerSetasList = typeUnifyTask.oup.smallerThan(a, nextSetAsList);
+      List<Set<UnifyPair>> notInherited = smallerSetasList.stream()
+        .filter(x -> !((Constraint<UnifyPair>) x).isInherited())
+        .collect(Collectors.toCollection(ArrayList::new));
+      List<Set<UnifyPair>> notErased = new ArrayList<>();
+      notInherited.forEach(x -> notErased.addAll(typeUnifyTask.oup.smallerEqThan(x, smallerSetasList)));
+      List<Set<UnifyPair>> erased = new ArrayList<>(smallerSetasList);
+      erased.removeAll(notErased);
+      nextSetAsList.removeAll(erased);
+
+      context.logger().debug("Removed: " + erased);
+
+      context.logger().debug("Not Removed: " + nextSetAsList);
+
+    }
+    return false;
+  }
+
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/VarianceCase.java

@@ -0,0 +1,132 @@
+package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
+
+import de.dhbwstuttgart.typeinference.constraints.Constraint;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
+import de.dhbwstuttgart.typeinference.unify.model.UnifyPair;
+import de.dhbwstuttgart.util.Tuple;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+
+public abstract class VarianceCase {
+
+  public static VarianceCase createFromVariance(int variance, boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    return switch (variance) {
+      case 0    -> new UnknownVarianceCase(isOderConstraint, typeUnifyTask, context);
+      case 1    -> new ContravarianceCase(isOderConstraint, typeUnifyTask, context);
+      case -1   -> new CovarianceCase(isOderConstraint, typeUnifyTask, context);
+      case 2    -> new InvarianceOrConstraintCase(isOderConstraint, typeUnifyTask, context);
+      default   -> throw new RuntimeException("Invalid variance: " + variance);
+    };
+  }
+
+  protected final boolean isOderConstraint;
+  protected final TypeUnifyTask typeUnifyTask;
+  protected final UnifyContext context;
+
+  /**
+   * Aktueller Fall
+   */
+  public Set<UnifyPair> a;
+
+  /**
+   * Liste der Faelle für die parallele Verarbeitung
+   * Enthaelt Elemente, die nicht in Relation zu aktuellem Fall in der
+   * Variablen a stehen. Diese muesse auf alle Faelle bearbeitet werden,
+   * Deshalb wird ihre Berechnung parallel angestossen.
+   */
+  public List<Set<UnifyPair>> nextSetasListRest = new ArrayList<>();
+
+  /**
+   * Liste der Faelle, bei dem Receiver jeweils "? extends" enthaelt bzw. nicht enthaelt
+   * In der Regel ist dies genau ein Element
+   * Dieses Element wird später aus nextSetasList geloescht, wenn das jeweils andere Element zum Erfolg
+   * gefuehrt hat.
+   */
+  public List<Set<UnifyPair>> nextSetasListOderConstraints = new ArrayList<>();
+
+
+  protected VarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+    this.isOderConstraint = isOderConstraint;
+    this.typeUnifyTask = typeUnifyTask;
+    this.context = context;
+  }
+
+  /**
+   *  Selects values for the next iteration in the run method:
+   *  - a : The element to ???
+   *  - nextSetAsList: The list of cases that have no relation to the selected a and will have to be worked on
+   *  - nextSetasListOderConstraints: The list of cases of which the receiver contains "? extends", typically one element
+   */
+  public abstract void selectNextData(
+    TypeUnifyTask typeUnifyTask,
+    List<Set<UnifyPair>> nextSetAsList,
+    Optional<UnifyPair> optOrigPair
+  );
+
+  /**
+   *
+   */
+  public abstract CompletableFuture<ComputationResults> computeParallel(
+    Set<Set<UnifyPair>> elems,
+    Set<UnifyPair> eq,
+    List<Set<Constraint<UnifyPair>>> oderConstraints,
+    IFiniteClosure fc,
+    int rekTiefe,
+    Set<UnifyPair> methodSignatureConstraint,
+    List<Set<UnifyPair>> nextSetAsList,
+    Set<UnifyPair> sameEqSet,
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> aParDef
+  );
+
+  /**
+   *
+   */
+  public abstract void applyComputedResults(
+    Set<Set<UnifyPair>> result,
+    Set<Set<UnifyPair>> currentThreadResult,
+    Set<UnifyPair> compResult,
+    Set<UnifyPair> compRes
+  );
+
+  /**
+   *
+   * @return If the current iteration should be broken out of
+   */
+  public abstract boolean eraseInvalidSets(
+    int rekTiefe,
+    Set<Set<UnifyPair>> aParDef,
+    List<Set<UnifyPair>> nextSetAsList
+  );
+
+  /**
+   * Wrapper class for the parallel computation results
+   */
+  public static class ComputationResults {
+    public Set<Set<UnifyPair>> mainResult;
+    public Set<Set<Set<UnifyPair>>> forkResults;
+
+    public ComputationResults() {
+      this(new HashSet<>(), new HashSet<>());
+    }
+
+    public ComputationResults(Set<Set<UnifyPair>> mainResult) {
+      this(mainResult, new HashSet<>());
+    }
+
+    public ComputationResults(Set<Set<UnifyPair>> mainResult, Set<Set<Set<UnifyPair>>> forkResults) {
+      this.mainResult = mainResult;
+      this.forkResults = forkResults;
+    }
+
+    void addForkResult(Set<Set<UnifyPair>> forkResult) {
+      forkResults.add(forkResult);
+    }
+  }
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/distributeVariance.java

@@ -12,15 +12,12 @@ import de.dhbwstuttgart.typeinference.unify.model.UnifyType;
 
 public class distributeVariance extends visitUnifyTypeVisitor<Integer> {
 	
-	public static int inverseVariance(int variance) { 
-		Integer ret = 0;
-		if (variance == 1) {
-		   ret = -1;
-		}
-		if (variance == -1) {
-			ret = 1;
-		}
-		return ret;
+	public static int inverseVariance(int variance) {
+		return switch (variance) {
+			case 1 -> -1;
+			case -1 -> 1;
+			default -> 0;
+		};
 	}
 
 
@@ -42,7 +39,7 @@ public class distributeVariance extends visitUnifyTypeVisitor<Integer> {
 		List<UnifyType> param = new ArrayList<>(funnty.getTypeParams().get().length);
 		param.addAll(Arrays.asList(funnty.getTypeParams().get()));
 		UnifyType resultType = param.remove(param.size()-1);
-		Integer htInverse = inverseVariance(ht);
+		int htInverse = inverseVariance(ht);
 		param = param.stream()
 				     .map(x -> x.accept(this, htInverse))
 				     .collect(Collectors.toCollection(ArrayList::new));

src/main/java/de/dhbwstuttgart/typeinference/unify/interfaces/IFiniteClosure.java

@@ -1,6 +1,7 @@
 package de.dhbwstuttgart.typeinference.unify.interfaces;
 
-import java.util.List;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.Optional;
 import java.util.Set;
 
@@ -18,9 +19,8 @@ import org.antlr.v4.runtime.Token;
  * 
  * @author Florian Steurer
  */
-public interface IFiniteClosure {
+public interface IFiniteClosure extends ISerializableData {
 	
-	public void setLogTrue();
 	/**
 	 * Returns all types of the finite closure that are subtypes of the argument.
 	 * @return The set of subtypes of the argument.
@@ -74,5 +74,5 @@ public interface IFiniteClosure {
 	public Set<UnifyType> getChildren(UnifyType t);
 	public Set<UnifyType> getAllTypesByName(String typeName);
 
-	public int compare(UnifyType rhsType, UnifyType rhsType2, PairOperator pairop);
+	public int compare(UnifyType rhsType, UnifyType rhsType2, PairOperator pairop, UnifyContext context);
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/ExtendsType.java

@@ -1,8 +1,9 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.Set;
 
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -11,7 +12,7 @@ import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
 /**
  * An extends wildcard type "? extends T". 
  */
-public final class ExtendsType extends WildcardType {
+public final class ExtendsType extends WildcardType implements ISerializableData  {
 	
 	public <T> UnifyType accept(UnifyTypeVisitor<T> visitor, T ht) {
 		return visitor.visit(this, ht);
@@ -23,9 +24,6 @@ public final class ExtendsType extends WildcardType {
 	 */
 	public ExtendsType(UnifyType extendedType) {
 		super("? extends " + extendedType.getName(), extendedType);
-		if (extendedType instanceof ExtendsType) {
-			System.out.print("");
-		}
 	}
 
 	/**
@@ -92,5 +90,21 @@ public final class ExtendsType extends WildcardType {
 		return "? extends " + wildcardedType;
 	}
 
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("wildcardedType", this.wildcardedType.toSerial(keyStorage));
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage).assertType(SerialMap.class);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static ExtendsType fromSerial(SerialMap data, UnifyContext context) {
+		return new ExtendsType(
+			UnifyType.fromSerial(data.getMap("wildcardedType"), context)
+		);
+	}
 	
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/FiniteClosure.java

@@ -1,16 +1,22 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import java.io.FileWriter;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.typeinference.unify.TypeUnifyTaskHelper;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
+import de.dhbwstuttgart.util.Logger;
 import java.io.IOException;
 import java.io.Writer;
-import java.lang.reflect.Modifier;
-import java.sql.Array;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Hashtable;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import java.util.function.BiFunction;
@@ -18,40 +24,28 @@ import java.util.function.BinaryOperator;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
-import com.google.common.collect.Ordering;
-
 //PL 18-02-05/18-04-05 Unifier durch Matcher ersetzt
 //muss greater noch ersetzt werden ja erledigt 18--04-05
 import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.parser.SourceLoc;
-import de.dhbwstuttgart.parser.scope.JavaClassName;
-import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
-import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
-import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
-import de.dhbwstuttgart.typeinference.unify.MartelliMontanariUnify;
 
 import de.dhbwstuttgart.typeinference.unify.Match;
 import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
-import de.dhbwstuttgart.typeinference.unify.interfaces.IUnify;
 import de.dhbwstuttgart.util.Pair;
 import org.antlr.v4.runtime.Token;
-import org.apache.commons.io.output.NullWriter;
 
 /**
  * The finite closure for the type unification
  * @author Florian Steurer
  */
-public class FiniteClosure //extends Ordering<UnifyType> //entfernt PL 2018-12-11
-implements IFiniteClosure  {
+public class FiniteClosure implements IFiniteClosure, ISerializableData {
 
 	final JavaTXCompiler compiler;
+	final PlaceholderRegistry placeholderRegistry;
+
+	Logger logger;
 
-	Writer logFile;
-	static Boolean log = false;
-	public void setLogTrue() {
-		log = true;
-	}
 	/**
 	 * A map that maps every type to the node in the inheritance graph that contains that type.
 	 */
@@ -81,9 +75,10 @@ implements IFiniteClosure  {
 	/**
 	 * Creates a new instance using the inheritance tree defined in the pairs.
 	 */
-	public FiniteClosure(Set<UnifyPair> pairs, Writer logFile, JavaTXCompiler compiler) {
+	public FiniteClosure(Set<UnifyPair> pairs, Logger logger, JavaTXCompiler compiler, PlaceholderRegistry placeholderRegistry) {
 		this.compiler = compiler;
-		this.logFile = logFile;
+		this.placeholderRegistry = placeholderRegistry;
+		this.logger = logger;
 		this.pairs = new HashSet<>(pairs);
 		inheritanceGraph = new HashMap<UnifyType, Node<UnifyType>>();
 		
@@ -132,7 +127,7 @@ implements IFiniteClosure  {
 		}
 
 		// Build the alternative representation with strings as keys
-		strInheritanceGraph = new HashMap<>();
+		strInheritanceGraph = TypeUnifyTaskHelper.getPresizedHashMap(inheritanceGraph.size());
 		for(UnifyType key : inheritanceGraph.keySet()) {
 			if(!strInheritanceGraph.containsKey(key.getName()))
 				strInheritanceGraph.put(key.getName(), new HashSet<>());
@@ -141,13 +136,13 @@ implements IFiniteClosure  {
 		}
 	}
 	
-	public FiniteClosure(Set<UnifyPair> constraints, Writer writer) {
-		this(constraints, writer, null);
+	public FiniteClosure(Set<UnifyPair> constraints, Logger logger, PlaceholderRegistry placeholderRegistry) {
+		this(constraints, logger, null, placeholderRegistry);
 	}
 
 	void testSmaller() {
 		UnifyType tq1, tq2, tq3;
-		tq1 = new ExtendsType(PlaceholderType.freshPlaceholder());
+		tq1 = new ExtendsType(PlaceholderType.freshPlaceholder(placeholderRegistry));
 		List<UnifyType> l1 = new ArrayList<>();
 		List<UnifyType> l2 = new ArrayList<>();
 		l1.add(tq1);
@@ -166,7 +161,7 @@ implements IFiniteClosure  {
 		
 		Set<UnifyType> ret;
 		if ((ret = smallerHash.get(new hashKeyType(type))) != null) {
-			//System.out.println(greaterHash);
+			//context.logger().info(greaterHash);
 			return new HashSet<>(ret);
 		}
 		
@@ -207,7 +202,7 @@ implements IFiniteClosure  {
 				result.add(new Pair<>(t, fBounded));
 			}
 			catch (StackOverflowError e) {
-				System.out.println("");
+				// context.logger().info("");
 			}
 			
 			// if C<...> <* C<...> then ... (third case in definition of <*)
@@ -244,9 +239,9 @@ implements IFiniteClosure  {
 					result.add(new Pair<>(theta1.apply(sigma), fBounded));
 			}
 		}
-		
-		HashSet<UnifyType> resut = result.stream().map(x -> x.getKey()).collect(Collectors.toCollection(HashSet::new));
-		if(resut.equals(types.stream().map(x -> x.getKey()).collect(Collectors.toCollection(HashSet::new))))
+
+		HashSet<UnifyType> resut = result.stream().map(Pair::getKey).collect(Collectors.toCollection(HashSet::new));
+		if(resut.equals(types.stream().map(Pair::getKey).collect(Collectors.toCollection(HashSet::new))))
 			return resut;
 		return computeSmaller(result);
 	}
@@ -278,9 +273,9 @@ implements IFiniteClosure  {
 	@Override
 	//Eingefuegt PL 2018-05-24 F-Bounded Problematik
 	public Set<UnifyType> greater(UnifyType type, Set<UnifyType> fBounded, SourceLoc location) {
-		Set<UnifyType> ret;
-		if ((ret = greaterHash.get(new hashKeyType(type))) != null) {
-			//System.out.println(greaterHash);
+		Set<UnifyType> ret = greaterHash.get(new hashKeyType(type));
+		if (ret != null) {
+			//context.logger().info(greaterHash);
 			return new HashSet<>(ret);
 		}
 	
@@ -330,7 +325,7 @@ implements IFiniteClosure  {
 			Set<UnifyType> fBoundedNew = new HashSet<>(fBounded);
 			fBoundedNew.add(theta1);
 			Set<UnifyType> theta2Set = candidate.getContentOfPredecessors();
-			//System.out.println("");
+			//context.logger().info("");
 			for(UnifyType theta2 : theta2Set) {
 				result.add(theta2.apply(sigma));
 				PairResultFBounded.add(new Pair<>(theta2.apply(sigma), fBoundedNew));
@@ -364,7 +359,7 @@ implements IFiniteClosure  {
 					    return ((match.match(termList).isPresent()) || x);
 					};
 					//if (parai.getName().equals("java.lang.Integer")) {
-					//	System.out.println("");
+					//	context.logger().info("");
 					//}
 					BinaryOperator<Boolean> bo = (a,b) -> (a || b);
 					if (lfBounded.stream().reduce(false,f,bo)) {
@@ -377,7 +372,7 @@ implements IFiniteClosure  {
 					}
 				}
 				permuteParams(paramCandidates).forEach(x -> result.add(t.setTypeParams(x)));
-				//System.out.println("");
+				//context.logger().info("");
 			}
 		}
 		
@@ -437,7 +432,7 @@ implements IFiniteClosure  {
 					    return ((match.match(termList).isPresent()) || x);
 					};
 					if (parai.getName().equals("java.lang.Integer")) {
-						System.out.println("");
+						context.logger().info("");
 					}
 					BinaryOperator<Boolean> bo = (a,b) -> (a || b);
 					if (fBounded.stream().reduce(false,f,bo)) continue; //F-Bounded Endlosrekursion
@@ -476,7 +471,7 @@ implements IFiniteClosure  {
 		}
 		
 		HashSet<UnifyType> resut = result.stream().map(x -> x.getKey()).collect(Collectors.toCollection(HashSet::new));
-		System.out.println(resut);
+		context.logger().info(resut);
 		if(resut.equals(types.stream().map(x -> x.getKey()).collect(Collectors.toCollection(HashSet::new))))
 			return resut;
 		return computeGreater(result);
@@ -512,35 +507,42 @@ implements IFiniteClosure  {
 	public Set<UnifyType> grArg(ReferenceType type, Set<UnifyType> fBounded) {
 		Set<UnifyType> result = new HashSet<UnifyType>();
 		result.add(type);	
-        smaller(type, fBounded).forEach(x -> result.add(new SuperType(x)));
-        greater(type,fBounded).forEach(x -> result.add(new ExtendsType(x)));
+		smaller(type, fBounded).forEach(x -> result.add(new SuperType(x)));
+		greater(type,fBounded).forEach(x -> result.add(new ExtendsType(x)));
 		return result;
 	}
 	
 	@Override
 	public Set<UnifyType> grArg(FunNType type, Set<UnifyType> fBounded) {
-		Set<UnifyType> result = new HashSet<UnifyType>();
+		Set<UnifyType> smaller = smaller(type, fBounded);
+		Set<UnifyType> greater = greater(type, fBounded);
+
+		Set<UnifyType> result = new HashSet<UnifyType>((int)((1 + smaller.size() + greater.size()) * 1.5));
 		result.add(type);	
-        smaller(type, fBounded).forEach(x -> result.add(new SuperType(x)));
-        greater(type, fBounded).forEach(x -> result.add(new ExtendsType(x)));
+		smaller.forEach(x -> result.add(new SuperType(x)));
+		greater.forEach(x -> result.add(new ExtendsType(x)));
 		return result;
 	}
 	
 	@Override
 	public Set<UnifyType> grArg(ExtendsType type, Set<UnifyType> fBounded) {
-		Set<UnifyType> result = new HashSet<UnifyType>();
-		result.add(type);
 		UnifyType t = type.getExtendedType();
-		greater(t, fBounded).forEach(x -> result.add(new ExtendsType(x)));
+		Set<UnifyType> greater = greater(t, fBounded);
+
+		Set<UnifyType> result = new HashSet<UnifyType>((int)((1 + greater.size()) * 1.5));
+		result.add(type);
+		greater.forEach(x -> result.add(new ExtendsType(x)));
 		return result;
 	}
 
 	@Override
 	public Set<UnifyType> grArg(SuperType type, Set<UnifyType> fBounded) {
-		Set<UnifyType> result = new HashSet<UnifyType>();
-		result.add(type);
 		UnifyType t = type.getSuperedType();
-		smaller(t, fBounded).forEach(x -> result.add(new SuperType(x)));
+		Set<UnifyType> smaller = smaller(t, fBounded);
+
+		Set<UnifyType> result = TypeUnifyTaskHelper.getPresizedHashSet(1 + smaller.size());
+		result.add(type);
+		smaller.forEach(x -> result.add(new SuperType(x)));
 		return result;
 	}
 	
@@ -572,29 +574,33 @@ implements IFiniteClosure  {
 	
 	@Override
 	public Set<UnifyType> smArg(ExtendsType type, Set<UnifyType> fBounded) {
-		Set<UnifyType> result = new HashSet<UnifyType>();
-		result.add(type);
 		UnifyType t = type.getExtendedType();
-		result.add(t);	
-        smaller(t, fBounded).forEach(x -> { 
-        	result.add(new ExtendsType(x));
-        	result.add(x); 
-        });
+		Set<UnifyType> smaller = smaller(t, fBounded);
+
+		Set<UnifyType> result = TypeUnifyTaskHelper.getPresizedHashSet(2 * (1 + smaller.size()));
+		result.add(type);
+		result.add(t);
+		smaller.forEach(x -> {
+			result.add(new ExtendsType(x));
+			result.add(x);
+		});
 		return result;
 	}
 	
 
 	@Override
 	public Set<UnifyType> smArg(SuperType type, Set<UnifyType> fBounded) {
-		Set<UnifyType> result = new HashSet<UnifyType>();
-		result.add(type);
 		UnifyType t = type.getSuperedType();
-		result.add(t);	
-//*** ACHTUNG das koennte FALSCH sein PL 2018-05-23 evtl. HashSet durch smArg durchschleifen	
-        greater(t, fBounded).forEach(x -> { 
-        	result.add(new SuperType(x));
-        	result.add(x); 
-        });
+		Set<UnifyType> greater = greater(t, fBounded);
+
+		Set<UnifyType> result = TypeUnifyTaskHelper.getPresizedHashSet(2 * (1 + greater.size()));
+		result.add(type);
+		result.add(t);
+		//*** ACHTUNG das koennte FALSCH sein PL 2018-05-23 evtl. HashSet durch smArg durchschleifen
+		greater.forEach(x -> {
+			result.add(new SuperType(x));
+			result.add(x);
+		});
 		return result;
 	}
 	
@@ -609,7 +615,7 @@ implements IFiniteClosure  {
 	public Set<UnifyType> getAllTypesByName(String typeName) {
 		if(!strInheritanceGraph.containsKey(typeName))
 			return new HashSet<>();
-		return strInheritanceGraph.get(typeName).stream().map(x -> x.getContent()).collect(Collectors.toCollection(HashSet::new));
+		return strInheritanceGraph.get(typeName).stream().map(Node::getContent).collect(Collectors.toCollection(HashSet::new));
 	}
 
 	@Override
@@ -698,10 +704,10 @@ implements IFiniteClosure  {
 	}
 	*/
 	
-	public int compare (UnifyType left, UnifyType right, PairOperator pairop) {
-		try {logFile.write("left: "+ left + " right: " + right + " pairop: " + pairop +"\n");} catch (IOException ie) {}
-		if (left.getName().equals("Matrix") || right.getName().equals("Matrix")) 
-			System.out.println("");
+	public int compare (UnifyType left, UnifyType right, PairOperator pairop, UnifyContext context) {
+		logger.debug(() -> "left: "+ left + " right: " + right + " pairop: " + pairop +"\n");
+		// if (left.getName().equals("Matrix") || right.getName().equals("Matrix"))
+		// 	context.logger().info("");
 		/*
 		pairop = PairOperator.SMALLERDOTWC;
 		List<UnifyType> al = new ArrayList<>();
@@ -752,19 +758,14 @@ implements IFiniteClosure  {
 			}
 		}
 		UnifyPair up = new UnifyPair(left, right, pairop);
-		TypeUnifyTask unifyTask = new TypeUnifyTask();
+		TypeUnifyTask unifyTask = new TypeUnifyTask(context);
 		HashSet<UnifyPair> hs = new HashSet<>();
 		hs.add(up);
 		Set<UnifyPair> smallerRes = unifyTask.applyTypeUnificationRules(hs, this);
 		
 		//if (left.getName().equals("Vector") || right.getName().equals("AbstractList")) 
-		{try { 
-			logFile.write("\nsmallerRes: " + smallerRes);//"smallerHash: " + greaterHash.toString());
-			logFile.flush();
-		}
-		catch (IOException e) {
-			System.err.println("no LogFile");}}
-		
+		logger.debug(() -> "\nsmallerRes: " + smallerRes);//"smallerHash: " + greaterHash.toString());
+
 		//Gleichungen der Form a <./=. Theta oder Theta <./=. a oder a <./=. b sind ok.
 		Predicate<UnifyPair> delFun = x -> !((x.getLhsType() instanceof PlaceholderType || 
 											 x.getRhsType() instanceof PlaceholderType)
@@ -772,12 +773,7 @@ implements IFiniteClosure  {
 													 ((WildcardType)x.getLhsType()).getWildcardedType().equals(x.getRhsType()))
 											 );
 		long smallerLen = smallerRes.stream().filter(delFun).count();
-		try { 
-			logFile.write("\nsmallerLen: " + smallerLen +"\n");
-			logFile.flush();
-		}
-		catch (IOException e) {
-			System.err.println("no LogFile");}
+		logger.debug(() -> "\nsmallerLen: " + smallerLen +"\n");
 		if (smallerLen == 0) return -1;
 		else {
 			up = new UnifyPair(right, left, pairop);
@@ -787,13 +783,8 @@ implements IFiniteClosure  {
 			Set<UnifyPair> greaterRes = unifyTask.applyTypeUnificationRules(hs, this);
 			
 			//if (left.getName().equals("Vector") || right.getName().equals("AbstractList")) 
-			{try { 
-				logFile.write("\ngreaterRes: " + greaterRes);//"smallerHash: " + greaterHash.toString());
-				logFile.flush();
-			}
-			catch (IOException e) {
-				System.err.println("no LogFile");}}
-			
+			logger.debug(() -> "\ngreaterRes: " + greaterRes);//"smallerHash: " + greaterHash.toString());
+
 			//Gleichungen der Form a <./=. Theta oder Theta <./=. a oder a <./=. b sind ok. 
 			long greaterLen = greaterRes.stream().filter(delFun).count();
 			if (greaterLen == 0) return 1;
@@ -803,4 +794,18 @@ implements IFiniteClosure  {
 			}
 		}	
 	}
+
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("pairs", SerialList.fromMapped(this.pairs, unifyPair -> unifyPair.toSerial(keyStorage)));
+		return serialized;
+	}
+
+	public static FiniteClosure fromSerial(SerialMap data, UnifyContext context, KeyStorage keyStorage) {
+		var pairList = data.getList("pairs").assertListOfUUIDs();
+		Set<UnifyPair> pairs = pairList.stream()
+			.map(pairData -> UnifyPair.fromSerial(pairData, context, keyStorage)).collect(Collectors.toSet());
+		return new FiniteClosure(pairs, context.logger(), context.placeholderRegistry());
+	}
+
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/FunInterfaceType.java

@@ -1,14 +1,17 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import de.dhbwstuttgart.parser.scope.JavaClassName;
-import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
 
-import java.lang.reflect.Modifier;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
-public class FunInterfaceType extends ReferenceType  {
+public class FunInterfaceType extends ReferenceType implements ISerializableData {
     final List<UnifyType> intfArgTypes;
     final UnifyType intfReturnType;
     final List<String> generics;
@@ -46,4 +49,29 @@ public class FunInterfaceType extends ReferenceType  {
 
         return args;
     }
+
+    @Override
+    public SerialMap toSerial(KeyStorage keyStorage) {
+        var serializedWrapper = super.toSerial(keyStorage);
+        SerialMap serialized = serializedWrapper.getMap("object");
+
+        serialized.put("intfArgTypes", SerialList.fromMapped(intfArgTypes, u -> u.toSerial(keyStorage)));
+        serialized.put("intfReturnType", intfReturnType.toSerial(keyStorage));
+        serialized.put("generics", SerialList.fromMapped(generics, SerialValue::new));
+
+        return serializedWrapper;
+    }
+
+    public static FunInterfaceType fromSerial(SerialMap data, UnifyContext context) {
+        var name = data.getValue("name").getOf(String.class);
+        var params = data.getList("params").assertListOfMaps().stream().map(
+          paramData -> UnifyType.fromSerial(paramData, context)).toList();
+        var intfArgTypes = data.getList("intfArgTypes").assertListOfMaps().stream().map(
+          argTypeData -> UnifyType.fromSerial(argTypeData, context)).toList();
+        var intfReturnType = UnifyType.fromSerial(data.getMap("intfReturnType"), context);
+        var generics = data.getList("generics").assertListOfValues().stream().map(
+          generic -> generic.getOf(String.class)).toList();
+
+        return new FunInterfaceType(name, new TypeParams(params), intfArgTypes, intfReturnType, generics);
+    }
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/FunNType.java

@@ -1,8 +1,13 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.HashMap;
+import java.util.List;
 import java.util.Set;
 
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -12,7 +17,7 @@ import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
  * A real function type in java.
  * @author Florian Steurer
  */
-public class FunNType extends UnifyType {
+public class FunNType extends UnifyType implements ISerializableData {
 
 	public <T> UnifyType accept(UnifyTypeVisitor<T> visitor, T ht) {
 		return visitor.visit(this, ht);
@@ -76,7 +81,7 @@ public class FunNType extends UnifyType {
 	}
 
 	@Override
-	public Boolean wrongWildcard() {
+	public boolean wrongWildcard() {
 		return (new ArrayList<UnifyType>(Arrays.asList(getTypeParams()
 				.get())).stream().filter(x -> (x instanceof WildcardType)).findFirst().isPresent());
 	}
@@ -99,5 +104,22 @@ public class FunNType extends UnifyType {
 
 		return other.getTypeParams().equals(typeParams);
 	}
-	
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("params", SerialList.fromMapped(this.typeParams.get(), param -> param.toSerial(keyStorage)));
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static FunNType fromSerial(SerialMap data, UnifyContext context) {
+		List<UnifyType> params = data.getList("params").assertListOfMaps().stream().map(
+			paramData -> UnifyType.fromSerial(paramData, context)).toList();
+		return new FunNType(new TypeParams(params));
+	}
+
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/OrderingUnifyPair.java

@@ -1,5 +1,6 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
@@ -26,9 +27,11 @@ import de.dhbwstuttgart.util.Pair;
 public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 	
 	protected IFiniteClosure fc;
-	
-	public OrderingUnifyPair(IFiniteClosure fc) {
+	protected UnifyContext context;
+
+	public OrderingUnifyPair(IFiniteClosure fc, UnifyContext context) {
 		this.fc = fc;
+		this.context = context;
 	}
 	
 	/*
@@ -39,18 +42,13 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		try {
 		//if (left.getRhsType() instanceof WildcardType || right.getRhsType() instanceof WildcardType) {//PL 2019-01-12 ausgetauscht
 		if (((PlaceholderType)left.getLhsType()).isInnerType() && ((PlaceholderType)right.getLhsType()).isInnerType()) {
-			return fc.compare(left.getRhsType(), right.getRhsType(), PairOperator.SMALLERDOTWC);
+			return fc.compare(left.getRhsType(), right.getRhsType(), PairOperator.SMALLERDOTWC, context);
 		}
 			else	 {
-				return fc.compare(left.getRhsType(), right.getRhsType(), PairOperator.SMALLERDOT);
+				return fc.compare(left.getRhsType(), right.getRhsType(), PairOperator.SMALLERDOT, context);
 		}}
 		catch (ClassCastException e) {
-			try {
-			((FiniteClosure)fc).logFile.write("ClassCastException: " + left.toString() + " " + left.getGroundBasePair() + "\n\n");
-			((FiniteClosure)fc).logFile.flush();
-			}
-			catch (IOException ie) {
-			}
+			((FiniteClosure)fc).logger.debug(() -> "ClassCastException: " + left.toString() + " " + left.getGroundBasePair() + "\n\n");
 			return -99;
 		}
 	}
@@ -58,7 +56,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 	/*
 	public int compareEq (UnifyPair left, UnifyPair right) {
 		if (left == null || right == null)
-			System.out.println("Fehler");
+			context.logger().info("Fehler");
 		if (left.getLhsType() instanceof PlaceholderType) {
 			return fc.compare(left.getRhsType(), right.getRhsType(), left.getPairOp());
 		}
@@ -79,18 +77,18 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 						&& (((ExtendsType)right).getExtendedType().getName().equals("java.util.Vector"))
 						&& (((ReferenceType)((ExtendsType)right).getExtendedType()).getTypeParams().iterator().next() instanceof ExtendsType)))
 				{
-					System.out.println("");
+					// context.logger().info("");
 				}
 				if (((right instanceof SuperType) && (((SuperType)right).getSuperedType().getName().equals("java.lang.Object")))
 		||((left instanceof SuperType) && (((SuperType)left).getSuperedType().getName().equals("java.lang.Object"))))
 {
-						System.out.println("");
+						// context.logger().info("");
 					}
 		}
 			else	 {
 				up = new UnifyPair(left, right, PairOperator.SMALLERDOT);
 		}
-		TypeUnifyTask unifyTask = new TypeUnifyTask();
+		TypeUnifyTask unifyTask = new TypeUnifyTask(context);
 		HashSet<UnifyPair> hs = new HashSet<>();
 		hs.add(up);
 		Set<UnifyPair> smallerRes = unifyTask.applyTypeUnificationRules(hs, fc);
@@ -106,11 +104,11 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 						&& (((ExtendsType)right).getExtendedType().getName().equals("java.util.Vector"))
 						&& (((ReferenceType)((ExtendsType)right).getExtendedType()).getTypeParams().iterator().next() instanceof ExtendsType)))
 				{
-					System.out.println("");
+					// context.logger().info("");
 				}
 				if (right instanceof SuperType) 
 					{
-						System.out.println("");
+						// context.logger().info("");
 					}
 			}
 				else	 {
@@ -172,85 +170,81 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		left.add(p2);
 		left.add(p4);
 		*/
-		
 
-		Set<UnifyPair> lefteq = left.stream()
-				.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> righteq = right.stream()
-				.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> leftle = left.stream()
-				.filter(x -> ((x.getLhsType() instanceof PlaceholderType || x.getRhsType() instanceof PlaceholderType) 
-						      && x.getPairOp() == PairOperator.SMALLERDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> rightle = right.stream()
-				.filter(x -> ((x.getLhsType() instanceof PlaceholderType || x.getRhsType() instanceof PlaceholderType) 
-						      && x.getPairOp() == PairOperator.SMALLERDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> leftlewc = left.stream()
-				.filter(x -> ((x.getLhsType() instanceof PlaceholderType || x.getRhsType() instanceof PlaceholderType) 
-						      && x.getPairOp() == PairOperator.SMALLERDOTWC))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> rightlewc = right.stream()
-				.filter(x -> ((x.getLhsType() instanceof PlaceholderType || x.getRhsType() instanceof PlaceholderType) 
-						      && x.getPairOp() == PairOperator.SMALLERDOTWC))
-				.collect(Collectors.toCollection(HashSet::new));
-		//System.out.println(left.toString());
+		Set<UnifyPair> lefteq = new HashSet<>();
+		Set<UnifyPair> leftle = new HashSet<>();
+		Set<UnifyPair> leftlewc = new HashSet<>();
+		Set<UnifyPair> lefteqOder = new HashSet<>();
+		Set<UnifyPair> lefteqRet = new HashSet<>();
+		Set<UnifyPair> leftleOder = new HashSet<>();
+		for (var x : left) {
+			boolean isLeftPlaceholder = x.getLhsType() instanceof PlaceholderType;
+			boolean isRightPlaceholder = x.getRhsType() instanceof PlaceholderType;
+			boolean hasPlaceholder = isLeftPlaceholder || isRightPlaceholder;
+
+			if (isLeftPlaceholder && x.getPairOp() == PairOperator.EQUALSDOT) lefteq.add(x);
+			if (hasPlaceholder && x.getPairOp() == PairOperator.SMALLERDOT) leftle.add(x);
+			if (hasPlaceholder && x.getPairOp() == PairOperator.SMALLERDOTWC) leftlewc.add(x);
+
+			UnifyPair y = x.getGroundBasePair();
+			boolean isBasePairLeftPlaceholder = y.getLhsType() instanceof PlaceholderType;
+			boolean isBasePairRightPlaceholder = y.getRhsType() instanceof PlaceholderType;
+			if (isBasePairLeftPlaceholder && !isBasePairRightPlaceholder && x.getPairOp() == PairOperator.EQUALSDOT) {
+				lefteqOder.add(x);
+			}
+			else if (isBasePairRightPlaceholder && ((PlaceholderType)y.getRhsType()).getOrCons() == (byte)-1) {
+				lefteqRet.add(x);
+			}
+			else if (x.getPairOp() == PairOperator.SMALLERDOT) {
+				leftleOder.add(x);
+			}
+		}
+
+
+		Set<UnifyPair> righteq = new HashSet<>();
+		Set<UnifyPair> rightle = new HashSet<>();
+		Set<UnifyPair> rightlewc = new HashSet<>();
+		Set<UnifyPair> righteqOder = new HashSet<>();
+		Set<UnifyPair> righteqRet = new HashSet<>();
+		Set<UnifyPair> rightleOder = new HashSet<>();
+		for (var x : right) {
+			boolean isLeftPlaceholder = x.getLhsType() instanceof PlaceholderType;
+			boolean isRightPlaceholder = x.getRhsType() instanceof PlaceholderType;
+			boolean hasPlaceholder = isLeftPlaceholder || isRightPlaceholder;
+
+			if (isLeftPlaceholder && x.getPairOp() == PairOperator.EQUALSDOT) righteq.add(x);
+			if (hasPlaceholder && x.getPairOp() == PairOperator.SMALLERDOT) 	rightle.add(x);
+			if (hasPlaceholder && x.getPairOp() == PairOperator.SMALLERDOTWC) rightlewc.add(x);
+
+			UnifyPair y = x.getGroundBasePair();
+			boolean isBasePairLeftPlaceholder = y.getLhsType() instanceof PlaceholderType;
+			boolean isBasePairRightPlaceholder = y.getRhsType() instanceof PlaceholderType;
+			if (isBasePairLeftPlaceholder && !isBasePairRightPlaceholder && x.getPairOp() == PairOperator.EQUALSDOT) {
+				righteqOder.add(x);
+			}
+			else if (isBasePairRightPlaceholder && ((PlaceholderType)y.getRhsType()).getOrCons() == (byte)-1) {
+				righteqRet.add(x);
+			}
+			else if (x.getPairOp() == PairOperator.SMALLERDOT) {
+				rightleOder.add(x);
+			}
+		}
+
+		//context.logger().info(left.toString());
 		//Fall 2
 		//if (lefteq.iterator().next().getLhsType().getName().equals("AJO")) {
 		//	System.out.print("");
 		//}
 		
 		//ODER-CONSTRAINT
-		Set<UnifyPair> leftBase = left.stream().map(x -> x.getGroundBasePair()).collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> rightBase = right.stream().map(x -> x.getGroundBasePair()).collect(Collectors.toCollection(HashSet::new));
+		// Set<UnifyPair> leftBase = left.stream().map(x -> x.getGroundBasePair()).collect(Collectors.toCollection(HashSet::new));
+		// Set<UnifyPair> rightBase = right.stream().map(x -> x.getGroundBasePair()).collect(Collectors.toCollection(HashSet::new));
 
-		Set<UnifyPair> lefteqOder = left.stream()
-				.filter(x -> { UnifyPair y = x.getGroundBasePair();
-				/*try {
-					((FiniteClosure)fc).logFile.write("leftBase: " + leftBase.toString() +"\n");
-					((FiniteClosure)fc).logFile.write("rightBase: " + rightBase.toString() +"\n\n");
-					((FiniteClosure)fc).logFile.write("left: " + left.toString() +"\n");
-					((FiniteClosure)fc).logFile.write("right: " + right.toString() +"\n\n");
-					((FiniteClosure)fc).logFile.write("y: " + y.toString() +"\n");
-					((FiniteClosure)fc).logFile.write("y.getLhsType() : " + y.getLhsType() .toString() +"\n\n");
-					((FiniteClosure)fc).logFile.write("y.getRhsType(): " + y.getRhsType().toString() +"\n");
-					((FiniteClosure)fc).logFile.write("x.getPairOp(): " + x.getPairOp().toString() +"\n\n");
-					}
-					catch (IOException ie) {
-					}	*/
-	               return (y.getLhsType() instanceof PlaceholderType && 
-	            		   !(y.getRhsType() instanceof PlaceholderType) && 
-	            		   x.getPairOp() == PairOperator.EQUALSDOT);})
-				.collect(Collectors.toCollection(HashSet::new));
 		left.removeAll(lefteqOder);
-		Set<UnifyPair> righteqOder = right.stream()
-				.filter(x -> { UnifyPair y = x.getGroundBasePair(); 
-	               return (y.getLhsType() instanceof PlaceholderType && 
-	            		   !(y.getRhsType() instanceof PlaceholderType) && 
-	            		   x.getPairOp() == PairOperator.EQUALSDOT);})
-				.collect(Collectors.toCollection(HashSet::new));
-		right.removeAll(righteqOder);
-		Set<UnifyPair> lefteqRet = left.stream()
-				.filter(x -> { UnifyPair y = x.getGroundBasePair(); 
-	               return (y.getRhsType() instanceof PlaceholderType && 
-	            		   ((PlaceholderType)y.getRhsType()).getOrCons() == (byte)-1);})
-				.collect(Collectors.toCollection(HashSet::new));
 		left.removeAll(lefteqRet);
-		Set<UnifyPair> righteqRet = right.stream()
-				.filter(x -> { UnifyPair y = x.getGroundBasePair(); 
-	               return (y.getRhsType() instanceof PlaceholderType && 
-	            		   ((PlaceholderType)y.getRhsType()).getOrCons() == (byte)-1);})
-				.collect(Collectors.toCollection(HashSet::new));
+		right.removeAll(righteqOder);
 		right.removeAll(righteqRet);
-		Set<UnifyPair> leftleOder = left.stream()
-				.filter(x -> (x.getPairOp() == PairOperator.SMALLERDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		Set<UnifyPair> rightleOder = right.stream()
-				.filter(x -> (x.getPairOp() == PairOperator.SMALLERDOT))
-				.collect(Collectors.toCollection(HashSet::new));
-		
+
 		/*
 		synchronized(this) {
 					try {
@@ -272,89 +266,73 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		*/
 		
 		
-		Integer compareEq;
+		int compareEq;
 		if (lefteqOder.size() == 1 && righteqOder.size() == 1 && lefteqRet.size() == 1 && righteqRet.size() == 1) {
 			Match m = new Match();
-			if ((compareEq = compareEq(lefteqOder.iterator().next().getGroundBasePair(), righteqOder.iterator().next().getGroundBasePair())) == -1) {
-				ArrayList<UnifyPair> matchList = 
-						rightleOder.stream().map(x -> { 
-							UnifyPair leftElem = leftleOder.stream()
+			compareEq = compareEq(lefteqOder.iterator().next().getGroundBasePair(), righteqOder.iterator().next().getGroundBasePair());
+
+			if (compareEq == -1) {
+				ArrayList<UnifyPair> matchList =
+						rightleOder.stream().map(x -> {
+								UnifyPair leftElem = leftleOder.stream()
 														     .filter(y -> y.getGroundBasePair().getLhsType().equals(x.getGroundBasePair().getLhsType()))
-														     .findAny().get(); 
-							return new UnifyPair(x.getRhsType(), leftElem.getRhsType(), PairOperator.EQUALSDOT);})
-											.collect(Collectors.toCollection(ArrayList::new));
-				if (m.match(matchList).isPresent()) {
-					//try { ((FiniteClosure)fc).logFile.write("result1: -1 \n\n"); } catch (IOException ie) {}
-					return -1;
-				}
-				else {
-					//try { ((FiniteClosure)fc).logFile.write("result1: 0 \n\n"); } catch (IOException ie) {}
-					return 0;
-				}
+														     .findAny().orElseThrow();
+								return new UnifyPair(x.getRhsType(), leftElem.getRhsType(), PairOperator.EQUALSDOT);}
+							)
+							.collect(Collectors.toCollection(ArrayList::new));
+
+				return (m.match(matchList).isPresent()) ? -1 : 0;
 			} else if (compareEq == 1) {
-				ArrayList<UnifyPair> matchList = 
-						leftleOder.stream().map(x -> { 
+				ArrayList<UnifyPair> matchList =
+						leftleOder.stream().map(x -> {
 							UnifyPair rightElem = rightleOder.stream()
-									                        .filter(y -> 
-									                        	y.getGroundBasePair().getLhsType().equals(x.getGroundBasePair().getLhsType()))
-									                        .findAny().get(); 
-														return new UnifyPair(x.getRhsType(), rightElem.getRhsType(), PairOperator.EQUALSDOT);})
-											.collect(Collectors.toCollection(ArrayList::new));
-				if (m.match(matchList).isPresent()) {
-					//try { ((FiniteClosure)fc).logFile.write("result2: 1 \n\n"); } catch (IOException ie) {}
-					return 1;
-				}
-				else {
-					//try { ((FiniteClosure)fc).logFile.write("result2: 0 \n\n"); } catch (IOException ie) {}
-					return 0;
-				}
+								.filter(y -> y.getGroundBasePair().getLhsType().equals(x.getGroundBasePair().getLhsType()))
+								.findAny().orElseThrow();
+							return new UnifyPair(x.getRhsType(), rightElem.getRhsType(), PairOperator.EQUALSDOT);}
+						)
+						.collect(Collectors.toCollection(ArrayList::new));
+				return (m.match(matchList).isPresent()) ? 1 : 0;
 			} else {
 				/*
-				synchronized(this) {
-					try {
-						((FiniteClosure)fc).logFile.write("leftBase: " + leftBase.toString() +"\n");
-						((FiniteClosure)fc).logFile.write("rightBase: " + rightBase.toString() +"\n\n");
-						((FiniteClosure)fc).logFile.write("left: " + left.toString() +"\n");
-						((FiniteClosure)fc).logFile.write("right: " + right.toString() +"\n\n");
-						((FiniteClosure)fc).logFile.write("lefteqOder: " + lefteqOder.toString() +"\n");
-						((FiniteClosure)fc).logFile.write("righteqOder: " + righteqOder.toString() +"\n\n");
-						((FiniteClosure)fc).logFile.write("lefteqRet: " + lefteqRet.toString() +"\n");
-						((FiniteClosure)fc).logFile.write("righteqRet: " + righteqRet.toString() +"\n\n");
-						((FiniteClosure)fc).logFile.write("leftleOder: " + leftleOder.toString() +"\n");
-						((FiniteClosure)fc).logFile.write("rightleOder: " + rightleOder.toString() +"\n\n");
-						((FiniteClosure)fc).logFile.write("result3: 0 \n\n");
-						((FiniteClosure)fc).logFile.flush();
-					}
-					catch (IOException ie) {
-					}
-				}
+					((FiniteClosure)fc).logFile.write("leftBase: " + leftBase.toString() +"\n");
+					((FiniteClosure)fc).logFile.write("rightBase: " + rightBase.toString() +"\n\n");
+					((FiniteClosure)fc).logFile.write("left: " + left.toString() +"\n");
+					((FiniteClosure)fc).logFile.write("right: " + right.toString() +"\n\n");
+					((FiniteClosure)fc).logFile.write("lefteqOder: " + lefteqOder.toString() +"\n");
+					((FiniteClosure)fc).logFile.write("righteqOder: " + righteqOder.toString() +"\n\n");
+					((FiniteClosure)fc).logFile.write("lefteqRet: " + lefteqRet.toString() +"\n");
+					((FiniteClosure)fc).logFile.write("righteqRet: " + righteqRet.toString() +"\n\n");
+					((FiniteClosure)fc).logFile.write("leftleOder: " + leftleOder.toString() +"\n");
+					((FiniteClosure)fc).logFile.write("rightleOder: " + rightleOder.toString() +"\n\n");
+					((FiniteClosure)fc).logFile.write("result3: 0 \n\n");
+					((FiniteClosure)fc).logFile.flush();
 				*/
 				return 0;
 			}
 		}
 		
 		
-		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof ExtendsType && leftle.size() == 1  && righteq.size() == 0 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof ExtendsType && leftle.size() == 1  && righteq.isEmpty() && rightle.size() == 1) {
 			return 1;
 		}
 		//Fall 2
-		if (lefteq.size() == 0 && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof ExtendsType && rightle.size() == 1) {
+		if (lefteq.isEmpty() && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof ExtendsType && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 3
-		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof SuperType && leftle.size() == 1  && righteq.size() == 0 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof SuperType && leftle.size() == 1  && righteq.isEmpty() && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 3
-		if (lefteq.size() == 0 && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof SuperType && rightle.size() == 1) {
+		if (lefteq.isEmpty() && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof SuperType && rightle.size() == 1) {
 			return 1;
 		}
 		//Fall 5
-		if (lefteq.size() == 1 && leftle.size() == 0 && righteq.size() == 1 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && leftle.isEmpty() && righteq.size() == 1 && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 5
-		if (lefteq.size() == 1 && leftle.size() == 1 && righteq.size() == 1 && rightle.size() == 0) {
+		if (lefteq.size() == 1 && leftle.size() == 1 && righteq.size() == 1 && rightle.isEmpty()) {
 			return 1;
 		}
 		//Fall 5
@@ -362,7 +340,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 			return 0;
 		}
 		// Nur Paare a =. Theta
-		if (leftle.size() == 0 && rightle.size() == 0 && leftlewc.size() == 0 && rightlewc.size() ==0) {
+		if (leftle.isEmpty() && rightle.isEmpty() && leftlewc.isEmpty() && rightlewc.isEmpty()) {
 			Stream<UnifyPair> lseq = lefteq.stream(); //left.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT));
 			Stream<UnifyPair> rseq = righteq.stream(); //right.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT));
 			BinaryOperator<HashMap<UnifyType,UnifyPair>> combiner = (x,y) -> { x.putAll(y); return x;};
@@ -370,13 +348,10 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 			lseq = lseq.filter(x -> !(hm.get(x.getLhsType()) == null));//NOCHMALS UEBERPRUEFEN!!!!
 			lseq = lseq.filter(x -> !x.equals(hm.get(x.getLhsType()))); //Elemente die gleich sind muessen nicht verglichen werden
 			Optional<Integer> si = lseq.map(x -> compareEq(x, hm.get(x.getLhsType()))).reduce((x,y)-> { if (x == y) return x; else return 0; } );
-			if (!si.isPresent()) return 0;
-			else return si.get();
+			return si.orElse(0);
 		}
 		//Fall 1 und 4
-		if (lefteq.size() >= 1 && righteq.size() >= 1 && (leftlewc.size() > 0 || rightlewc.size() > 0)) {
-			if (lefteq.iterator().next().getLhsType().getName().equals("D")) 
-				System.out.print("");
+		if (!lefteq.isEmpty() && !righteq.isEmpty() && (!leftlewc.isEmpty() || !rightlewc.isEmpty())) {
 			//Set<PlaceholderType> varsleft = lefteq.stream().map(x -> (PlaceholderType)x.getLhsType()).collect(Collectors.toCollection(HashSet::new));
 			//Set<PlaceholderType> varsright = righteq.stream().map(x -> (PlaceholderType)x.getLhsType()).collect(Collectors.toCollection(HashSet::new));
 			//filtern des Paares a = Theta, das durch a <. Thata' generiert wurde (nur im Fall 1 relevant)  andere Substitutioen werden rausgefiltert
@@ -397,12 +372,12 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 				//TODO: Hier wird bei Wildcards nicht das richtige compare aufgerufen PL 18-04-20
 				Pair<Integer, Set<UnifyPair>> int_Unifier = compare(lseq.getRhsType(), rseq.getRhsType());
 				Unifier uni = new Unifier();
-				int_Unifier.getValue().get().forEach(x -> uni.add((PlaceholderType) x.getLhsType(), x.getRhsType()));
-				if (!lseq.getRhsType().getName().equals(rseq.getRhsType().getName()) 
-					|| leftlewc.size() == 0 || rightlewc.size() == 0) return int_Unifier.getKey();
+				int_Unifier.getValue().orElseThrow().forEach(x -> uni.add((PlaceholderType) x.getLhsType(), x.getRhsType()));
+				if (!lseq.getRhsType().getName().equals(rseq.getRhsType().getName())
+					|| leftlewc.isEmpty() || rightlewc.isEmpty()) return int_Unifier.getKey();
 				else {
-					Set <UnifyPair> lsleuni = leftlewc.stream().map(x -> uni.apply(x)).collect(Collectors.toCollection(HashSet::new));
-					Set <UnifyPair> rsleuni = rightlewc.stream().map(x -> uni.apply(x)).collect(Collectors.toCollection(HashSet::new));
+					Set <UnifyPair> lsleuni = leftlewc.stream().map(uni::apply).collect(Collectors.toCollection(HashSet::new));
+					Set <UnifyPair> rsleuni = rightlewc.stream().map(uni::apply).collect(Collectors.toCollection(HashSet::new));
 					BinaryOperator<HashMap<UnifyType,UnifyPair>> combiner = (x,y) -> { x.putAll(y); return x;};
 				
 					HashMap<UnifyType,UnifyPair> hm;
@@ -411,19 +386,19 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 					if (leftlewc.iterator().next().getLhsType() instanceof PlaceholderType) {
 						hm = rsleuni.stream().reduce(new HashMap<UnifyType,UnifyPair>(), (x, y)-> { x.put(y.getLhsType(),y); return x; }, combiner);
 						Stream<UnifyPair> lslewcstr = lsleuni.stream().filter(x -> !(hm.get(x.getLhsType()) == null));
-						si = lslewcstr.map(x -> fc.compare(x.getRhsType(), hm.get(x.getLhsType()).getRhsType(), PairOperator.SMALLERDOTWC)).reduce((x,y)-> { if (x == y) return x; else return 0; } );
+						si = lslewcstr.map(x -> fc.compare(x.getRhsType(), hm.get(x.getLhsType()).getRhsType(), PairOperator.SMALLERDOTWC, context)).reduce((x,y)-> { if (x == y) return x; else return 0; } );
 					}
 					//4. Fall
 					else {
 						hm = rsleuni.stream().reduce(new HashMap<UnifyType,UnifyPair>(), (x, y)-> { x.put(y.getRhsType(),y); return x; }, combiner);
 						Stream<UnifyPair> lslewcstr = lsleuni.stream().filter(x -> !(hm.get(x.getRhsType()) == null));
-						si = lslewcstr.map(x -> fc.compare(x.getLhsType(), hm.get(x.getRhsType()).getLhsType(), PairOperator.SMALLERDOTWC)).reduce((x,y)-> { if (x == y) return x; else return 0; } );
+						si = lslewcstr.map(x -> fc.compare(x.getLhsType(), hm.get(x.getRhsType()).getLhsType(), PairOperator.SMALLERDOTWC, context)).reduce((x,y)-> { if (x == y) return x; else return 0; } );
 					}
-					if (!si.isPresent()) return 0;
-					else return si.get();
+					return si.orElse(0);
 				}
 			} else {
-				if (leftlewc.size() > 0) {
+				if (!leftlewc.isEmpty()) {
+					/*
 					Set<UnifyPair> subst;
 					subst = leftlewc.stream().map(x -> { 
 						if (x.getLhsType() instanceof PlaceholderType) {
@@ -432,6 +407,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 						else {
 							return new UnifyPair(x.getRhsType(), x.getLhsType(), PairOperator.EQUALSDOT);
 						}}).collect(Collectors.toCollection(HashSet::new));
+					 */
 					Unifier uni = new Unifier();
 					lseq = uni.apply(lseq);
 				}

src/main/java/de/dhbwstuttgart/typeinference/unify/model/PairOperator.java

@@ -46,4 +46,15 @@ public enum PairOperator {
 			default: return "=."; // EQUALSDOT
 		}
 	}
+
+	public static PairOperator fromString(String op) {
+		switch (op) {
+			case "<": return SMALLER;
+			case "<.": return SMALLERDOT;
+			case "<!=.": return SMALLERNEQDOT;
+			case "<.?": return SMALLERDOTWC;
+			case "=.": return EQUALSDOT;
+			default: throw new RuntimeException("Unknown PairOperator: " + op);
+		}
+	}
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/PlaceholderType.java

@@ -1,119 +1,96 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import java.io.File;
-import java.io.FileWriter;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Random;
-import java.util.Set;
-
-import de.dhbwstuttgart.typeinference.unify.distributeVariance;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.PlaceholderRegistry;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Set;
 
 /**
  * An unbounded placeholder type.
  * @author Florian Steurer
  */
 public final class PlaceholderType extends UnifyType{
-	
-	/**
-	 * Static list containing the names of all existing placeholders.
-	 * Used for generating fresh placeholders.
-	 */
-	public static final ArrayList<String> EXISTING_PLACEHOLDERS = new ArrayList<String>();
-	
-	/**
-	 * Prefix of auto-generated placeholder names.
-	 */
-	protected static String nextName = "gen_";
-	
-	/**
-	 * Random number generator used to generate fresh placeholder name.
-	 */
-	protected static Random rnd = new Random(43558747548978L);
-	
+
 	/**
 	 * True if this object was auto-generated, false if this object was user-generated.
 	 */
 	private final boolean IsGenerated;
-	
-	
+
+
 	/**
-	 * isWildcardable gibt an, ob ein Wildcardtyp dem PlaceholderType zugeordnet werden darf 
+	 * isWildcardable gibt an, ob ein Wildcardtyp dem PlaceholderType zugeordnet werden darf
 	 */
-	private boolean wildcardable = true;  
-	
+	private boolean wildcardable = true;
+
 	/**
 	 * is innerType gibt an, ob der Type des PlaceholderType innerhalb eines Typkonstruktorsverwendet wird
 	 */
-	private boolean innerType = false;  
-	
+	private boolean innerType = false;
+
 	/**
-     * variance shows the variance of the pair
-     * 1: contravariant
-     * -1 covariant
-     * 0 invariant
-     * PL 2018-03-21
-     */
-    private int variance = 0;
-    
-    /*
-     * Fuer Oder-Constraints:
-     * orCons = 1: Receiver
-     * orCons = 0: Argument oder kein Oder-Constraint 
-     * orCons = -1: RetType
-     */
-    private byte orCons = 0;
-	
+	 * variance shows the variance of the pair
+	 * 1: contravariant
+	 * -1 covariant
+	 * 0 invariant
+	 * PL 2018-03-21
+	 */
+	private int variance = 0;
+
+	/*
+	 * Fuer Oder-Constraints:
+	 * orCons = 1: Receiver
+	 * orCons = 0: Argument oder kein Oder-Constraint
+	 * orCons = -1: RetType
+	 */
+	private byte orCons = 0;
+
 	/**
 	 * Creates a new placeholder type with the specified name.
 	 */
-	public PlaceholderType(String name) {
+	public PlaceholderType(String name, PlaceholderRegistry placeholderRegistry) {
 		super(name, new TypeParams());
-		EXISTING_PLACEHOLDERS.add(name); // Add to list of existing placeholder names
+		placeholderRegistry.addPlaceholder(name); // Add to list of existing placeholder names
 		IsGenerated = false; // This type is user generated
 	}
-	
-	
-	public PlaceholderType(String name, int variance) {
+
+
+	public PlaceholderType(String name, int variance, PlaceholderRegistry placeholderRegistry) {
 		super(name, new TypeParams());
-		EXISTING_PLACEHOLDERS.add(name); // Add to list of existing placeholder names
+		placeholderRegistry.addPlaceholder(name); // Add to list of existing placeholder names
 		IsGenerated = false; // This type is user generated
 		this.variance = variance;
 	}
-	
+
 	/**
-	 * Creates a new placeholdertype 
+	 * Creates a new placeholdertype
 	 * @param isGenerated true if this placeholder is auto-generated, false if it is user-generated.
 	 */
-	protected PlaceholderType(String name, boolean isGenerated) {
+	protected PlaceholderType(String name, boolean isGenerated, PlaceholderRegistry placeholderRegistry) {
 		super(name, new TypeParams());
-		EXISTING_PLACEHOLDERS.add(name); // Add to list of existing placeholder names
+		placeholderRegistry.addPlaceholder(name); // Add to list of existing placeholder names
 		IsGenerated = isGenerated;
 	}
-	
+
 	public <T> UnifyType accept(UnifyTypeVisitor<T> visitor, T ht) {
 		return visitor.visit(this, ht);
 	}
-	
+
 	/**
-	 * Creates a fresh placeholder type with a name that does so far not exist.
+	 * Creates a fresh placeholder type with a name that does so far not exist from the chars A-Z.
 	 * A user could later instantiate a type using the same name that is equivalent to this type.
 	 * @return A fresh placeholder type.
 	 */
-	public synchronized static PlaceholderType freshPlaceholder() {
-		String name = nextName + (char) (rnd.nextInt(22) + 97); // Returns random char between 'a' and 'z'
-		// Add random chars while the name is in use.
-		while(EXISTING_PLACEHOLDERS.contains(name)) {
-			name += (char) (rnd.nextInt(22) + 97); // Returns random char between 'a' and 'z'
-		}
-		return new PlaceholderType(name, true);
+	public static PlaceholderType freshPlaceholder(PlaceholderRegistry placeholderRegistry) {
+		var name = placeholderRegistry.generateFreshPlaceholderName();
+		return new PlaceholderType(name, true, placeholderRegistry);
 	}
-	
-	
+
+
 	/**
 	 * True if this placeholder is auto-generated, false if it is user-generated.
 	 */
@@ -124,51 +101,51 @@ public final class PlaceholderType extends UnifyType{
 	public void setVariance(int v) {
 		variance = v;
 	}
-	
+
 	public int getVariance() {
 		return variance;
 	}
-	
+
 	public void reversVariance() {
 		if (variance == 1) {
 			setVariance(-1);
 		} else {
-	    if (variance == -1) {
-			setVariance(1);
-		}}
+			if (variance == -1) {
+				setVariance(1);
+			}}
 	}
-	
+
 	public void setOrCons(byte i) {
 		orCons = i;
 	}
-	
+
 	public byte getOrCons() {
 		return orCons;
 	}
-	
+
 	public Boolean isWildcardable() {
 		return wildcardable;
 	}
 	public void disableWildcardtable() {
 		wildcardable = false;
 	}
-	
+
 	public void enableWildcardtable() {
 		wildcardable = true;
 	}
-	
-	public void setWildcardtable(Boolean wildcardable) {
+
+	public void setWildcardtable(boolean wildcardable) {
 		this.wildcardable = wildcardable;
 	}
-	
-	public Boolean isInnerType() {
+
+	public boolean isInnerType() {
 		return innerType;
 	}
-	
-	public void setInnerType(Boolean innerType) {
+
+	public void setInnerType(boolean innerType) {
 		this.innerType = innerType;
 	}
-	
+
 	@Override
 	Set<UnifyType> smArg(IFiniteClosure fc, Set<UnifyType> fBounded) {
 		return fc.smArg(this, fBounded);
@@ -178,17 +155,17 @@ public final class PlaceholderType extends UnifyType{
 	Set<UnifyType> grArg(IFiniteClosure fc, Set<UnifyType> fBounded) {
 		return fc.grArg(this, fBounded);
 	}
-	
+
 	@Override
 	public UnifyType setTypeParams(TypeParams newTp) {
 		return this; // Placeholders never have params.
 	}
-	
+
 	@Override
 	public int hashCode() {
 		return typeName.hashCode();
 	}
-	
+
 	@Override
 	UnifyType apply(Unifier unif) {
 		if(unif.hasSubstitute(this)) {
@@ -200,15 +177,15 @@ public final class PlaceholderType extends UnifyType{
 		}
 		return this;
 	}
-	
+
 	@Override
 	public boolean equals(Object obj) {
 		if(!(obj instanceof PlaceholderType))
 			return false;
-		
+
 		return ((PlaceholderType) obj).getName().equals(typeName);
 	}
-	
+
 
 	@Override
 	public Collection<PlaceholderType> getInvolvedPlaceholderTypes() {
@@ -216,4 +193,39 @@ public final class PlaceholderType extends UnifyType{
 		ret.add(this);
 		return ret;
 	}
+
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("name", this.typeName);
+		// Placeholders never make use of the typeParams
+		serialized.put("isGenerated", IsGenerated);
+		serialized.put("wildcardable", wildcardable);
+		serialized.put("isInnerType", innerType);
+		serialized.put("variance", variance);
+		serialized.put("orCons", orCons);
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static PlaceholderType fromSerial(SerialMap data, UnifyContext context) {
+		var name 				= data.getValue("name").getOf(String.class);
+		var isGenerated = data.getValue("isGenerated").getOf(Boolean.class);
+		var wildcardable = data.getValue("wildcardable").getOf(Boolean.class);
+		var isInnerType = data.getValue("isInnerType").getOf(Boolean.class);
+		var variance 		= data.getValue("variance").getOf(Integer.class);
+		var orCons 			= data.getValue("orCons").getOf(Number.class).byteValue();
+
+		var placeholderType = new PlaceholderType(name, isGenerated, context.placeholderRegistry());
+		placeholderType.setWildcardtable(wildcardable);
+		placeholderType.setInnerType(isInnerType);
+		placeholderType.setVariance(variance);
+		placeholderType.setOrCons(orCons);
+
+		return placeholderType;
+	}
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/ReferenceType.java

@@ -1,6 +1,10 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import java.util.HashMap;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.Set;
 
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -11,45 +15,51 @@ import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
  * @author Florian Steurer
  *
  */
-public class ReferenceType extends UnifyType {
-	
+public class ReferenceType extends UnifyType implements ISerializableData {
+
 	/**
 	 * The buffered hashCode
 	 */
 	private final int hashCode;
-	
+
 	/**
 	 * gibt an, ob der ReferenceType eine generische Typvariable ist
 	 */
 	private final boolean genericTypeVar;
-	
+
 
 	public <T> UnifyType accept(UnifyTypeVisitor<T> visitor, T ht) {
 		return visitor.visit(this, ht);
 	}
-	
-	public ReferenceType(String name, Boolean genericTypeVar) {
+
+	public ReferenceType(String name, boolean genericTypeVar) {
 		super(name, new TypeParams());
 		hashCode = 31 + 17 * typeName.hashCode() + 17 * typeParams.hashCode();
 		this.genericTypeVar = genericTypeVar;
 	}
-	
+
 	public ReferenceType(String name, UnifyType... params) {
 		super(name, new TypeParams(params));
 		hashCode = 31 + 17 * typeName.hashCode() + 17 * typeParams.hashCode();
 		genericTypeVar = false;
 	}
-	
+
 	public ReferenceType(String name, TypeParams params) {
 		super(name, params);
 		hashCode = 31 + 17 * typeName.hashCode() + 17 * typeParams.hashCode();
 		genericTypeVar = false;
 	}
 
-	public boolean isGenTypeVar () { 
+	private ReferenceType(String name, TypeParams params, boolean genericTypeVar) {
+		super(name, params);
+		hashCode = 31 + 17 * typeName.hashCode() + 17 * typeParams.hashCode();
+		this.genericTypeVar = genericTypeVar;
+	}
+
+	public boolean isGenTypeVar() {
 		return genericTypeVar;
 	}
-	
+
 	@Override
 	Set<UnifyType> smArg(IFiniteClosure fc, Set<UnifyType> fBounded) {
 		return fc.smArg(this, fBounded);
@@ -63,38 +73,59 @@ public class ReferenceType extends UnifyType {
 	@Override
 	UnifyType apply(Unifier unif) {
 		TypeParams newParams = typeParams.apply(unif);
-		
-		if(newParams.hashCode() == typeParams.hashCode() && newParams.equals(typeParams))
+
+		if (newParams.hashCode() == typeParams.hashCode() && newParams.equals(typeParams))
 			return this;
-		
+
 		return new ReferenceType(typeName, newParams);
 	}
-	
+
 	@Override
 	public UnifyType setTypeParams(TypeParams newTp) {
-		if(newTp.hashCode() == typeParams.hashCode() && newTp.equals(typeParams))
+		if (newTp.hashCode() == typeParams.hashCode() && newTp.equals(typeParams))
 			return this; // reduced the amount of objects created
 		return new ReferenceType(typeName, newTp);
 	}
-	
+
 	@Override
 	public int hashCode() {
 		return hashCode;
 	}
-	
+
 	@Override
 	public boolean equals(Object obj) {
-		if(!(obj instanceof ReferenceType))
+		if (!(obj instanceof ReferenceType))
 			return false;
-		
-		if(obj.hashCode() != this.hashCode())
+
+		if (obj.hashCode() != this.hashCode())
 			return false;
-		
+
 		ReferenceType other = (ReferenceType) obj;
-		
-		if(!other.getName().equals(typeName))
+
+		if (!other.getName().equals(typeName))
 			return false;
 
 		return other.getTypeParams().equals(typeParams);
 	}
-}
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("name", this.typeName);
+		serialized.put("params", SerialList.fromMapped(this.typeParams.get(), param -> param.toSerial(keyStorage)));
+		serialized.put("isGenericTypeVar", this.genericTypeVar);
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static ReferenceType fromSerial(SerialMap data, UnifyContext context) {
+		var name = data.getValue("name").getOf(String.class);
+		var params = data.getList("params").assertListOfMaps().stream().map(
+			paramData -> UnifyType.fromSerial(paramData, context)).toList();
+		var isGenericTypeVar = data.getValue("isGenericTypeVar").getOf(Boolean.class);
+		return new ReferenceType(name, new TypeParams(params), isGenericTypeVar);
+	}
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/model/SuperType.java

@@ -1,6 +1,9 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import java.util.HashMap;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.Set;
 
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -85,4 +88,26 @@ public final class SuperType extends WildcardType {
 		SuperType other = (SuperType) obj;
 		return other.getSuperedType().equals(wildcardedType);
 	}
+
+	@Override
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		serialized.put("wildcardedType", this.wildcardedType.toSerial(keyStorage));
+		serialized.put("params", SerialList.fromMapped(this.typeParams.get(), param -> param.toSerial(keyStorage)));
+
+		// create the wrapper and put this as the object
+		var serializedWrapper = super.toSerial(keyStorage);
+		serializedWrapper.put("object", serialized);
+		return serializedWrapper;
+	}
+
+	public static SuperType fromSerial(SerialMap data, UnifyContext context) {
+		var params = data.getList("params").assertListOfMaps().stream().map(
+			paramData -> UnifyType.fromSerial(paramData, context)).toList();
+		var superType = new SuperType(
+			UnifyType.fromSerial(data.getMap("wildcardedType"), context)
+		);
+		superType.setTypeParams(new TypeParams(params));
+		return superType;
+	}
 }

src/main/java/de/dhbwstuttgart/typeinference/unify/model/TypeParams.java

@@ -174,9 +174,9 @@ public final class TypeParams implements Iterable<UnifyType>{
 	
 	@Override
 	public String toString() {
-		String res = "";
+		StringBuilder res = new StringBuilder();
 		for(UnifyType t : typeParams)
-			res += t + ",";
+			res.append(t).append(",");
 		return "<" + res.substring(0, res.length()-1) + ">";
 	}
 

src/main/java/de/dhbwstuttgart/typeinference/unify/model/Unifier.java

@@ -50,8 +50,7 @@ public class Unifier implements Function<UnifyType, UnifyType>, Iterable<Entry<P
 		Unifier tempU = new Unifier(source, target);
 		// Every new substitution must be applied to previously added substitutions
 		// otherwise the unifier needs to be applied multiple times to unify two terms
-		for(PlaceholderType pt : substitutions.keySet())
-			substitutions.put(pt, substitutions.get(pt).apply(tempU));
+		substitutions.replaceAll((pt, ut) -> ut.apply(tempU));
 		substitutions.put(source, target);
 	}
 
@@ -93,8 +92,7 @@ public class Unifier implements Function<UnifyType, UnifyType>, Iterable<Entry<P
 		//	}
 		//}
 		if (!(p.getLhsType().equals(newLhs)) || !(p.getRhsType().equals(newRhs))) {//Die Anwendung von this hat was veraendert PL 2018-04-01
-			Set<UnifyPair> suniUnifyPair = new HashSet<>();
-			suniUnifyPair.addAll(thisAsPair.getAllSubstitutions());
+      Set<UnifyPair> suniUnifyPair = new HashSet<>(thisAsPair.getAllSubstitutions());
 			suniUnifyPair.add(thisAsPair);
 			if (p.getLhsType() instanceof PlaceholderType //&& newLhs instanceof PlaceholderType entfernt PL 2018-04-13
 					&& p.getPairOp() == PairOperator.EQUALSDOT) {
@@ -172,13 +170,13 @@ public class Unifier implements Function<UnifyType, UnifyType>, Iterable<Entry<P
 
 	@Override
 	public String toString() {
-		String result = "{ ";
+		StringBuilder result = new StringBuilder("{ ");
 		for(Entry<PlaceholderType, UnifyType> entry : substitutions.entrySet())
-			result += "(" + entry.getKey() + " -> " + entry.getValue() + "), ";
+			result.append("(").append(entry.getKey()).append(" -> ").append(entry.getValue()).append("), ");
 		if(!substitutions.isEmpty())
-			result = result.substring(0, result.length()-2);
-		result += " }";
-		return result;
+			result = new StringBuilder(result.substring(0, result.length() - 2));
+		result.append(" }");
+		return result.toString();
 	}
 
 	@Override

src/main/java/de/dhbwstuttgart/typeinference/unify/model/UnifyPair.java

@@ -1,23 +1,26 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
-import com.google.common.collect.ObjectArrays;
 import de.dhbwstuttgart.parser.SourceLoc;
-import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
-import org.antlr.v4.runtime.Token;
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialList;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialUUID;
+import de.dhbwstuttgart.typeinference.constraints.IConstraintElement;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Optional;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 
 /**
  * A pair which contains two types and an operator, e.q. (Integer <. a).
  * @author Florian Steurer
  */
-public class UnifyPair {
+public class UnifyPair implements IConstraintElement, ISerializableData {
 
 	private SourceLoc location;
 
@@ -151,8 +154,7 @@ public class UnifyPair {
 	}
 	
 	public Set<UnifyPair> getAllSubstitutions () {
-		Set<UnifyPair> ret = new HashSet<>();
-		ret.addAll(new ArrayList<>(getSubstitution()));
+    Set<UnifyPair> ret = new HashSet<>(new ArrayList<>(getSubstitution()));
 		if (basePair != null) {
 			ret.addAll(new ArrayList<>(basePair.getAllSubstitutions()));
 		}
@@ -199,7 +201,7 @@ public class UnifyPair {
 			
 	}
 	
-	public Boolean wrongWildcard() {
+	public boolean wrongWildcard() {
 		return lhs.wrongWildcard() || rhs.wrongWildcard();
 	}
 	
@@ -243,16 +245,16 @@ public class UnifyPair {
 	public String toString() {
 		String ret = "";
 		if (lhs instanceof PlaceholderType) {
-			ret = new Integer(((PlaceholderType)lhs).getVariance()).toString() + " "
+			ret = Integer.valueOf(((PlaceholderType)lhs).getVariance()).toString() + " "
 					+ "WC: " + ((PlaceholderType)lhs).isWildcardable()
 					+ ", IT: " + ((PlaceholderType)lhs).isInnerType();
 		}
 		if (rhs instanceof PlaceholderType) {
-			ret = ret + ", " + new Integer(((PlaceholderType)rhs).getVariance()).toString() + " " 
+			ret = ret + ", " + Integer.valueOf(((PlaceholderType)rhs).getVariance()).toString() + " "
 					+ "WC: " + ((PlaceholderType)rhs).isWildcardable()
 					+ ", IT: " + ((PlaceholderType)rhs).isInnerType();
 		}
-		var res =  "(" + lhs + " " + pairOp + " " + rhs + ", " + ret + ")"; //+ ", [" + getfBounded().toString()+ "])";
+		var res =  "(UP: " + lhs + " " + pairOp + " " + rhs + ", " + ret + ")"; //+ ", [" + getfBounded().toString()+ "])";
 		var location = this.getLocation();
 		if (location != null) {
 			res += "@" + location.line() + " in " + location.file();
@@ -269,6 +271,58 @@ public class UnifyPair {
 		return ret;
 	}
 	*/
+	private String serialUUID = null;
+
+	public SerialUUID toSerial(KeyStorage keyStorage) {
+		final String uuid = serialUUID == null ? keyStorage.getIdentifier() : serialUUID;
+		if (serialUUID == null) serialUUID = uuid;
+
+		if (!keyStorage.isAlreadySerialized(uuid)) {
+			SerialMap serialized = new SerialMap();
+			keyStorage.putSerialized(uuid, serialized);
+			serialized.put("lhs", this.lhs.toSerial(keyStorage));
+			serialized.put("rhs", this.rhs.toSerial(keyStorage));
+			serialized.put("op", this.pairOp.toString());
+			serialized.put("basePair", this.basePair == null ? null : this.basePair.toSerial(keyStorage));
+			serialized.put("location", this.location == null ? null : this.location.toSerial(keyStorage));
+			serialized.put("substitution", SerialList.fromMapped(this.substitution, unifyPair -> unifyPair.toSerial(keyStorage)));
+			serialized.put("fBounded", SerialList.fromMapped(this.fBounded, fbounded -> fbounded.toSerial(keyStorage)));
+		}
+		return new SerialUUID(uuid);
+	}
+
+	public static UnifyPair fromSerial(SerialUUID serialUUID, UnifyContext context, KeyStorage keyStorage) {
+		String uuid = serialUUID.uuid;
+		if (!keyStorage.isAlreadyUnserialized(uuid)) {
+			SerialMap data = keyStorage.getSerialized(uuid);
+			SerialMap lhsData = data.getMap("lhs");
+			SerialMap rhsData = data.getMap("rhs");
+			String opData = data.getValue("op").getOf(String.class);
+
+			UnifyPair pair = new UnifyPair(
+				UnifyType.fromSerial(lhsData, context),
+				UnifyType.fromSerial(rhsData, context),
+				PairOperator.fromString(opData)
+			);
+			// put the object into the storage before unserializing basePair recursively
+			keyStorage.putUnserialized(uuid, pair);
+
+			SerialList<SerialUUID> substitutionData = data.getList("substitution").assertListOfUUIDs();
+			SerialList<SerialMap> fBoundedData = data.getList("fBounded").assertListOfMaps();
+			SerialUUID basePairData = data.getUUIDOrNull("basePair");
+			SerialMap locationData = data.getMapOrNull("location");
+
+			pair.substitution = substitutionData.stream().map(substData -> UnifyPair.fromSerial(substData, context, keyStorage)).collect(Collectors.toSet());
+			pair.fBounded = fBoundedData.stream().map(fBoundData -> UnifyType.fromSerial(fBoundData, context)).collect(Collectors.toSet());
+			if (basePairData != null) {
+				pair.basePair = UnifyPair.fromSerial(basePairData, context, keyStorage);
+			}
+			if (locationData != null) {
+				pair.location = SourceLoc.fromSerial(locationData);
+			}
+		}
+		return keyStorage.getUnserialized(uuid, UnifyPair.class);
+	}
 }
 
 

src/main/java/de/dhbwstuttgart/typeinference/unify/model/UnifyType.java

@@ -1,12 +1,14 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
+import de.dhbwstuttgart.server.packet.dataContainers.KeyStorage;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialMap;
+import de.dhbwstuttgart.server.packet.dataContainers.serialized.SerialValue;
+import de.dhbwstuttgart.typeinference.unify.UnifyContext;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
 import java.util.Set;
 
-import de.dhbwstuttgart.syntaxtree.StatementVisitor;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
 
@@ -14,7 +16,7 @@ import de.dhbwstuttgart.typeinference.unify.interfaces.UnifyTypeVisitor;
  * Represents a java type.
  * @author Florian Steurer
  */
-public abstract class UnifyType {
+public abstract class UnifyType implements ISerializableData {
 	
 	/**
 	 * The name of the type e.q. "Integer", "? extends Integer" or "List" for (List<T>)
@@ -29,7 +31,7 @@ public abstract class UnifyType {
 	/**
 	 * Creates a new instance
 	 * @param name Name of the type (e.q. List for List<T>, Integer or ? extends Integer)
-	 * @param typeParams Parameters of the type (e.q. <T> for List<T>)
+	 * @param p Parameters of the type (e.q. <T> for List<T>)
 	 */
 	protected UnifyType(String name, TypeParams p) {
 		typeName = name;
@@ -87,23 +89,21 @@ public abstract class UnifyType {
 	
 	@Override
 	public String toString() {
-		String params = "";
+		StringBuilder params = new StringBuilder();
 		if(typeParams.size() != 0) {
 			for(UnifyType param : typeParams)
-				params += param.toString() + ",";
-			params = "<" + params.substring(0, params.length()-1) + ">";
+				params.append(param.toString()).append(",");
+			params = new StringBuilder("<" + params.substring(0, params.length() - 1) + ">");
 		}
 		
 		return typeName + params;
 	}
 
 	public Collection<PlaceholderType> getInvolvedPlaceholderTypes() {
-		ArrayList<PlaceholderType> ret = new ArrayList<>();
-		ret.addAll(typeParams.getInvolvedPlaceholderTypes());
-		return ret;
+    return new ArrayList<>(typeParams.getInvolvedPlaceholderTypes());
 	}
 	
-	public Boolean wrongWildcard() {//default
+	public boolean wrongWildcard() {//default
 		return false;
 	}
 
@@ -114,7 +114,40 @@ public abstract class UnifyType {
 
 	@Override
 	public boolean equals(Object obj) {
-		if(obj == null)return false;
+		if(obj == null) return false;
 		return this.toString().equals(obj.toString());
 	}
-}
+
+	public SerialMap toSerial(KeyStorage keyStorage) {
+		SerialMap serialized = new SerialMap();
+		String type = switch (this) {
+			case FunInterfaceType _ -> "funi";
+			case ReferenceType _ -> "ref";
+      case ExtendsType _ -> "ext";
+      case SuperType _ -> "sup";
+      case FunNType _ -> "funn";
+      case PlaceholderType _ -> "tph";
+      default -> throw new RuntimeException("No type defined for UnifyType of class " + this.getClass().getName());
+    };
+
+    serialized.put("type", type);
+		// we only insert null for the object and expect the child classes to call this and override the value with themselves
+		serialized.put("object", SerialValue.NULL);
+		return serialized;
+	}
+
+	public static UnifyType fromSerial(SerialMap data, UnifyContext context) {
+		var type = data.getValue("type").getOf(String.class);
+		var object = data.getMap("object");
+
+		return switch (type) {
+			case "funi" -> FunInterfaceType.fromSerial(object, context);
+			case "ref" -> ReferenceType.fromSerial(object, context);
+			case "ext" -> ExtendsType.fromSerial(object, context);
+			case "sup" -> SuperType.fromSerial(object, context);
+			case "funn" -> FunNType.fromSerial(object, context);
+			case "tph" -> PlaceholderType.fromSerial(object, context);
+			default -> throw new RuntimeException("Could not unserialize class of unhandled type " + type);
+		};
+	}
+}

src/main/java/de/dhbwstuttgart/typeinference/unify/model/WildcardType.java

@@ -1,5 +1,6 @@
 package de.dhbwstuttgart.typeinference.unify.model;
 
+import de.dhbwstuttgart.server.packet.dataContainers.ISerializableData;
 import java.util.ArrayList;
 import java.util.Collection;
 
@@ -7,7 +8,7 @@ import java.util.Collection;
  * A wildcard type that is either a ExtendsType or a SuperType.
  * @author Florian Steurer
  */
-public abstract class WildcardType extends UnifyType {
+public abstract class WildcardType extends UnifyType implements ISerializableData {
 	
 	/**
 	 * The wildcarded type, e.q. Integer for ? extends Integer. Never a wildcard type itself.
@@ -41,7 +42,7 @@ public abstract class WildcardType extends UnifyType {
 	}
 	
 	@Override
-	public Boolean wrongWildcard () {//This is an error
+	public boolean wrongWildcard () {//This is an error
 		return (wildcardedType instanceof WildcardType);
 	}
 	
@@ -65,8 +66,7 @@ public abstract class WildcardType extends UnifyType {
 
 	@Override
 	public Collection<PlaceholderType> getInvolvedPlaceholderTypes() {
-		ArrayList<PlaceholderType> ret = new ArrayList<>();
-		ret.addAll(wildcardedType.getInvolvedPlaceholderTypes());
+    ArrayList<PlaceholderType> ret = new ArrayList<>(wildcardedType.getInvolvedPlaceholderTypes());
 		return ret;
 	}
 }

src/main/java/de/dhbwstuttgart/util/Logger.java

@@ -0,0 +1,322 @@
+package de.dhbwstuttgart.util;
+
+import com.diogonunes.jcolor.Attribute;
+import de.dhbwstuttgart.core.ConsoleInterface;
+import de.dhbwstuttgart.server.SocketServer;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.Writer;
+import java.nio.file.Path;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.function.Supplier;
+import java.util.stream.Collectors;
+
+import static com.diogonunes.jcolor.Ansi.colorize;
+
+public class Logger {
+
+  public static final Logger NULL_LOGGER = new NullLogger();
+  private static final DateTimeFormatter timeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
+
+  protected final Writer writer;
+  protected final String prefix;
+
+  public Logger() {
+    this(null, "");
+  }
+
+  public Logger(String prefix) {
+    this(null, prefix);
+  }
+
+  public Logger(Writer writer, String prefix) {
+    this.prefix = (Objects.equals(prefix, "")) ? "" : "["+prefix+"] ";
+    this.writer = writer;
+  }
+
+  /**
+   * Create a new logger object from the path provided
+   *
+   * @param filePath  The path to the output file. Recommended file extension ".log"
+   * @return          The Logger object for this output file
+   */
+  public static Logger forFile(String filePath, String prefix) {
+    File file = Path.of(filePath).toFile();
+    try {
+      Writer fileWriter = new FileWriter(file);
+      return new Logger(fileWriter, prefix);
+    }
+    catch (IOException exception) {
+      throw new RuntimeException("Failed to created Logger for file " + filePath, exception);
+    }
+  }
+
+  /**
+   * Create a new logger object that inherits the writer of the given logger object
+   *
+   * @param logger    The old logger object that will provide the writer
+   * @return          The new prefix for the new logger object
+   */
+  public static Logger inherit(Logger logger, String newPrefix) {
+    return new Logger(logger.writer, newPrefix);
+  }
+
+  /**
+   * Tint the prefix in the color of the logLevel
+   * @param logLevel  The logLevel to set the tint to
+   * @return          The tinted string (using ANSI sequences)
+   */
+  protected String getPrefix(LogLevel logLevel) {
+    String fullPrefix = prefix + "[" + logLevel + "] ";
+    return switch (logLevel) {
+      case DEBUG    -> colorize(fullPrefix, Attribute.BRIGHT_MAGENTA_TEXT());
+      case INFO     -> colorize(fullPrefix, Attribute.BLUE_TEXT());
+      case WARNING  -> colorize(fullPrefix, Attribute.YELLOW_TEXT());
+      case ERROR    -> colorize(fullPrefix, Attribute.RED_TEXT());
+      case SUCCESS  -> colorize(fullPrefix, Attribute.GREEN_TEXT());
+    };
+  }
+
+  /**
+   * Print text to the output or error stream, depending on the logLevel
+   * @param s         The string to print
+   * @param logLevel  If logLevel == error, then print to stderr or print to stdout otherwise
+   */
+  protected void print(String s, LogLevel logLevel) {
+    String coloredPrefix = this.getPrefix(logLevel);
+
+    // if we are running the server, prepend the timestamp
+    if(SocketServer.isServerRunning()) {
+      String timestamp = LocalDateTime.now().format(timeFormatter);
+      coloredPrefix = "[" + timestamp + "] " + coloredPrefix;
+    }
+
+    // output to the correct output-stream
+    if (logLevel.getValue() == LogLevel.ERROR.getValue()) {
+      System.out.println(coloredPrefix + s);
+    }
+    else {
+      System.err.println(coloredPrefix + s);
+    }
+  }
+
+  public boolean isLogLevelActive(LogLevel logLevel) {
+    return logLevel.isHigherOrEqualTo(ConsoleInterface.logLevel);
+  }
+
+  /**
+   * Write text to the attached writer if there is any
+   * @param s   The string to print
+   */
+  protected void write(String s) {
+    if (writer != null && ConsoleInterface.writeLogFiles) {
+      // writing to file should only be done when necessary
+      synchronized (writer) {
+        try {
+          writer.write(s);
+        }
+        catch (IOException exception) {
+          throw new RuntimeException("Failed writing to file", exception);
+        }
+      }
+    }
+  }
+
+  /**
+   * Base method for logging a string value. Should mostly be used by the Logger internal functions that
+   * abstract the logLevel away from the parameters
+   *
+   * @hidden Only relevant for the Logger and very special cases with dynamic logLevel
+   * @param s         The text to log
+   * @param logLevel  The logLevel on which the text should be logged
+   */
+  public void log(String s, LogLevel logLevel) {
+    if (isLogLevelActive(logLevel)) {
+      this.print(s, logLevel);
+      this.write(s);
+    }
+  }
+  public void log(Supplier<String> supp, LogLevel logLevel) {
+    if (isLogLevelActive(logLevel)) {
+      this.log(supp.get(), logLevel);
+    }
+  }
+  public void log(Object obj, LogLevel logLevel) {
+    if (isLogLevelActive(logLevel)) {
+      this.log(obj.toString(), logLevel);
+    }
+  }
+
+
+  /**
+   * Output a debug message
+   * @param s The string to log
+   */
+  public void debug(String s) {
+    this.log(s, LogLevel.DEBUG);
+  }
+  public void debug(Object o) {
+    this.log(o, LogLevel.DEBUG);
+  }
+  public void debug(Supplier<String> supp) {
+    this.log(supp, LogLevel.DEBUG);
+  }
+
+  /**
+   * Output an info message
+   * @param s The string to log
+   */
+  public void info(String s) {
+    this.log(s, LogLevel.INFO);
+  }
+  public void info(Object o) {
+    this.log(o, LogLevel.INFO);
+  }
+  public void info(Supplier<String> supp) {
+    this.log(supp, LogLevel.INFO);
+  }
+
+  /**
+   * Output a warning message
+   * @param s The string to log
+   */
+  public void warn(String s) {
+    this.log(s, LogLevel.WARNING);
+  }
+  public void warn(Object o) {
+    this.log(o, LogLevel.WARNING);
+  }
+  public void warn(Supplier<String> supp) {
+    this.log(supp, LogLevel.WARNING);
+  }
+
+  /**
+   * Output an error message
+   * @param s The string to log
+   */
+  public void error(String s) {
+    this.log(s, LogLevel.ERROR);
+  }
+  public void error(Object o) {
+    this.log(o, LogLevel.ERROR);
+  }
+  public void error(Supplier<String> supp) {
+    this.log(supp, LogLevel.ERROR);
+  }
+
+
+  /**
+   * Output a success message
+   * @param s The string to log
+   */
+  public void success(String s) {
+    this.log(s, LogLevel.SUCCESS);
+  }
+  public void success(Object o) {
+    this.log(o, LogLevel.SUCCESS);
+  }
+  public void success(Supplier<String> supp) {
+    this.log(supp, LogLevel.SUCCESS);
+  }
+
+  /**
+   * Special logging function that prints a throwable object and all of its recursive causes (including stacktrace)
+   * as an error
+   *
+   * @param throwable The Throwable object to output
+   */
+  public void exception(Throwable throwable) {
+    // Format the exception output
+    String s = "Exception: " + throwable.getMessage() + "\n" +
+      Arrays.stream(throwable.getStackTrace()).map(stackTraceElement ->
+        " | " + stackTraceElement.toString()
+      ).collect(Collectors.joining("\n"));
+
+    // if there is a cause printed afterward, announce it with the print of the exception
+    if (throwable.getCause() != null) {
+      s += "\n\nCaused by: ";
+    }
+
+    // print the exception
+    this.error(s);
+
+    // print the cause recursively
+    if (throwable.getCause() != null) {
+      this.exception(throwable.getCause());
+    }
+  }
+
+  public void close() {
+    if (this.writer != null) {
+      try {
+        this.writer.close();
+      }
+      catch (IOException exception) {
+        throw new RuntimeException("Failed to close a loggers writer. Was it maybe already closed? ", exception);
+      }
+    }
+  }
+
+
+  /**
+   * An enum representing the different log levels as integers:
+   * <ul>
+   *  <li>DEBUG: highly specific output only for debugging</li>
+   *  <li>INFO: informational output about the current state of the program</li>
+   *  <li>WARNING: warnings about potential issues or an unexpected state</li>
+   *  <li>ERROR: invalid states, errors and exceptions</li>
+   *  <li>SUCCESS: successfully executed key steps of the program</li>
+   * </ul>
+   */
+  public enum LogLevel {
+    /** Highly specific output only for debugging */
+    DEBUG(0),
+    /** Informational output about the current state of the program */
+    INFO(1),
+    /** Warnings about potential issues or an unexpected state **/
+    WARNING(2),
+    /** Invalid states, errors and exceptions */
+    ERROR(3),
+    /** Successfully executed key steps of the program */
+    SUCCESS(4);
+
+    private final int value;
+    LogLevel(final int newValue) {
+      value = newValue;
+    }
+
+    public boolean isHigherOrEqualTo(LogLevel other) {
+      return this.value >= other.value;
+    }
+
+    public int getValue() {
+      return value;
+    }
+
+    public static LogLevel fromValue(int value) {
+      return switch (value) {
+        case 0 -> LogLevel.DEBUG;
+        case 1 -> LogLevel.INFO;
+        case 2 -> LogLevel.WARNING;
+        case 3 -> LogLevel.ERROR;
+        case 4 -> LogLevel.SUCCESS;
+        default -> throw new RuntimeException("Invalid log level value: " + value);
+      };
+    }
+  }
+
+
+  /**
+   * A special case of logger that will never output anything
+   */
+  private static class NullLogger extends Logger {
+    @Override
+    public void log(String s, LogLevel logLevel) {
+      // Do nothing. Yay
+    }
+  }
+}

src/main/java/de/dhbwstuttgart/util/Pair.java

@@ -3,37 +3,26 @@ package de.dhbwstuttgart.util;
 import java.util.Objects;
 import java.util.Optional;
 
-public class Pair<T, T1> {
-    private final T key;
-    private final T1 value;
+public class Pair<T, T1> extends Tuple<T, T1> {
 
-    public Pair(T a, T1 b) {
-        this.value = b;
-        this.key = a;
-    }
+  public Pair(T a, T1 b) {
+    super(a, b);
+  }
 
-    public Optional<T1> getValue() {
-        return Optional.of(value);
-    }
+  public Optional<T1> getValue() {
+    return Optional.of(second);
+  }
 
-    public T getKey() {
-        return key;
-    }
-    
-    public String toString() {
-    	return "(" + key.toString() + "," + value.toString() + ")\n";
-    }
+  public T getKey() {
+    return first;
+  }
 
-    @Override
-    public boolean equals(Object o) {
-        if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
-        Pair<?, ?> pair = (Pair<?, ?>) o;
-        return Objects.equals(key, pair.key) && Objects.equals(value, pair.value);
-    }
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    Pair<?, ?> pair = (Pair<?, ?>) o;
+    return Objects.equals(first, pair.first) && Objects.equals(second, pair.second);
+  }
 
-    @Override
-    public int hashCode() {
-        return Objects.hash(key, value);
-    }
 }

src/main/java/de/dhbwstuttgart/util/Tuple.java

@@ -0,0 +1,38 @@
+package de.dhbwstuttgart.util;
+
+import java.util.Objects;
+
+public class Tuple<T1, T2> {
+    protected final T1 first;
+    protected final T2 second;
+
+    public Tuple(T1 a, T2 b) {
+        this.second = b;
+        this.first = a;
+    }
+
+    public T1 getFirst() {
+        return first;
+    }
+
+    public T2 getSecond() {
+        return second;
+    }
+
+    public String toString() {
+    	return "(" + first.toString() + "," + second.toString() + ")\n";
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Tuple<?, ?> pair = (Tuple<?, ?>) o;
+        return Objects.equals(first, pair.first) && Objects.equals(second, pair.second);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(first, second);
+    }
+}

src/test/java/TestTypeDeployment.java

@@ -18,7 +18,7 @@ public class TestTypeDeployment {
     public void testTypeDeployment() throws Exception {
         var path = Path.of(System.getProperty("user.dir"), "/resources/bytecode/javFiles/Cycle.jav");
         var file = path.toFile();
-        var compiler = new JavaTXCompiler(file, false);
+        var compiler = new JavaTXCompiler(file);
         var parsedSource = compiler.sourceFiles.get(file);
         var tiResults = compiler.typeInference(file);
         Set<TypeInsert> tips = new HashSet<>();