feat: update parallelization for 0variance

independentTest.sh

@@ -9,7 +9,8 @@ mkdir $TDIR
 
 cd $TDIR
 git clone $REPO .
-git checkout feat/unify-server-0variance
+git checkout feat/unify-server
+# git checkout 93e1a8787cd94c73f4538f6a348f58613893a584
 # git checkout dad468368b86bdd5a3d3b2754b17617cee0a9107 # 1:55
 # git checkout a0c11b60e8c9d7addcbe0d3a09c9ce2924e9d5c0 # 2:25
 # git checkout 4cddf73e6d6c9116d3e1705c4b27a8e7f18d80c3 # 2:27
@@ -19,14 +20,14 @@ git checkout feat/unify-server-0variance
 # git checkout 1391206dfe59263cdb22f93371cfd1dd5465d97f # 1:29
 
 date "+%Y.%m.%d %H:%M:%S"
-
-mkdir testOut
-
-#mvn clean compile -DskipTests package
-#time java -jar target/JavaTXcompiler-0.1-jar-with-dependencies.jar resources/bytecode/javFiles/Merge.jav -vv -d testOut;
+# 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 test
+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... "

pom.xml

@@ -49,6 +49,11 @@ http://maven.apache.org/maven-v4_0_0.xsd">
 			<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>

resources/LaufzeitTests/DeeplyNested.jav

@@ -0,0 +1,51 @@
+class C1 {
+    C1 self() {
+        return this;
+    }
+}
+
+class C2 {
+    C2 self() {
+        return this;
+    }
+}
+
+class Example {
+    untypedMethod(var) {
+        return var.self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self()
+                  .self().self().self().self();
+    }
+}

resources/LaufzeitTests/GridSearch.jav

@@ -0,0 +1,43 @@
+import java.lang.Integer;
+import java.lang.Boolean;
+import java.util.Queue;
+import java.util.Vector;
+import java.util.List;
+import java.util.ArrayDeque;
+
+class Pos {
+    public Integer x;
+    public Integer y;
+    public Pos(Integer x, Integer y) {
+        this.x = x;
+        this.y = y;
+    }
+}
+
+class GridSearch {
+
+    Pos search(Vector<Vector<Boolean>> grid) {
+        var w = grid.size();
+        var h = grid.getFirst().size();
+
+        // keep a queue on which cells to check
+        var cellQueue = new ArrayDeque<Pos>();
+        cellQueue.add(new Pos(0,0));
+
+        while (!cellQueue.isEmpty()) {
+            var pos = cellQueue.poll();
+            // if the target was found: return the position
+            var value = grid.get(pos.x).get(pos.y);
+            if (value) {
+                return pos;
+            }
+
+            // keep searching on neighboring tiles
+            if (pos.x < w-1)    cellQueue.add(new Pos(pos.x + 1, pos.y));
+            if (pos.y < h-1)    cellQueue.add(new Pos(pos.x, pos.y + 1));
+        }
+
+        return (Pos)null;
+    }
+
+}

resources/LaufzeitTests/Mask.jav

@@ -0,0 +1,42 @@
+import java.util.List;
+import java.util.AbstractList;
+import java.util.Vector;
+import java.lang.Integer;
+
+class Pixel {
+    public color;
+}
+
+class Mask {
+
+    mask;
+
+    Mask(mask) {
+        this.mask = mask;
+    }
+
+    apply(pixels) {
+        var w = mask.size();
+        var h = mask.get(0).size();
+        var imgW = pixels.size();
+        var imgH = pixels.get(0).size();
+
+        for (var x = 0; x < imgW - w; x++) {
+            for (var y = 0; y < imgH - h; y++) {
+
+                var total = 0;
+                for (var xd = 0; xd < w; xd++) {
+                    for (var yd = 0; yd < h; yd++) {
+                        var p = pixels.get(x + xd).get(y + yd);
+                        var m = mask.get(xd).get(yd);
+                        total = total + (p.color * m);
+                    }
+                }
+
+                pixels.get(x).get(y).color = total;
+            }
+        }
+
+        return pixels;
+    }
+}

resources/LaufzeitTests/PascalsTriangle.jav

@@ -0,0 +1,39 @@
+import java.lang.Integer;
+import java.lang.Boolean;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+public class PascalsTriangle {
+
+    create(n) {
+        var rows = new ArrayList<ArrayList<Integer>>();
+        var evens = new ArrayList<ArrayList<Boolean>>();
+
+        if (n <= 0) return rows;
+        // first row
+        rows.add(new ArrayList<Integer>(1));
+        evens.add(new ArrayList<Boolean>(false));
+
+        for (int y = 1; y < n; y++) {
+            var row = new ArrayList<Integer>();
+            var evensRow = new ArrayList<Boolean>();
+            row.add(1);
+            evensRow.add(false);
+
+            for (int x = 1; x < y-1; x++) {
+                int tl = rows.getLast().get(x-1);
+                int tr = rows.getLast().get(x);
+                row.add(tl + tr);
+                evensRow.add(((tl + tr) % 2) == 1);
+            }
+
+            row.add(1);
+            rows.add(row);
+            evensRow.add(false);
+            evens.add(evensRow);
+        }
+
+        return rows;
+    }
+
+}

resources/bytecode/javFiles/Merge2.jav

@@ -0,0 +1,17 @@
+import java.util.List;
+import java.lang.Integer;
+//import java.util.Collection;
+
+public class Merge2  {
+
+	public merge(a, b) {
+     	a.addAll(b);
+		return a;
+	}
+
+  	public sort(in){
+    	var firstHalf = in.subList(1,2);
+    	return merge(sort(firstHalf), sort(in));
+    }
+    
+}

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

@@ -1,5 +1,6 @@
 package de.dhbwstuttgart.core;
 
+import de.dhbwstuttgart.server.SocketClient;
 import de.dhbwstuttgart.util.Logger;
 import java.io.File;
 import java.io.IOException;
@@ -7,8 +8,12 @@ import java.util.*;
 
 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<>();
@@ -16,7 +21,6 @@ public class ConsoleInterface {
     String outputPath = null;
     Iterator<String> it = Arrays.asList(args).iterator();
     Optional<Integer> serverPort = Optional.empty();
-    Optional<String> unifyServer = Optional.empty();
 
     if (args.length == 0) {
       System.out.println("No input files given. Get help with --help");
@@ -45,7 +49,7 @@ public class ConsoleInterface {
       } else if (arg.equals("--server-mode")) {
         serverPort = Optional.of(Integer.parseInt(it.next()));
       } else if (arg.equals("--unify-server")) {
-        unifyServer = Optional.of(it.next());
+        unifyServerUrl = Optional.of(it.next());
       } else if (arg.equals("--write-logs")) {
         ConsoleInterface.writeLogFiles = true;
       } else if (arg.startsWith("-v")) {
@@ -61,15 +65,15 @@ public class ConsoleInterface {
     }
 
     if (serverPort.isPresent()) {
-      if (unifyServer.isPresent()) throw new RuntimeException("Cannot use unifyServer when in server mode!");
-
+      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, unifyServer);
+      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

@@ -13,6 +13,10 @@ 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;
@@ -20,6 +24,7 @@ import de.dhbwstuttgart.syntaxtree.ParameterList;
 import de.dhbwstuttgart.syntaxtree.SourceFile;
 import de.dhbwstuttgart.syntaxtree.GenericDeclarationList;
 import de.dhbwstuttgart.syntaxtree.factory.ASTFactory;
+import de.dhbwstuttgart.syntaxtree.factory.NameGenerator;
 import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
 import de.dhbwstuttgart.syntaxtree.type.ExtendsWildcardType;
 import de.dhbwstuttgart.syntaxtree.type.GenericRefType;
@@ -81,29 +86,24 @@ public class JavaTXCompiler {
 	public final List<File> classPath;
 	private final File outputPath;
 
-	private final Optional<String> unifyServer;
-
 	public DirectoryClassLoader getClassLoader() {
 		return classLoader;
 	}
 
 	public JavaTXCompiler(File sourceFile) throws IOException, ClassNotFoundException {
-		this(Arrays.asList(sourceFile), List.of(), new File("."), Optional.empty());
+		this(Collections.singletonList(sourceFile), List.of(), new File("."));
 	}
 
 	public JavaTXCompiler(List<File> sourceFiles) throws IOException, ClassNotFoundException {
-		this(sourceFiles, List.of(), new File("."), Optional.empty());
+		this(sourceFiles, List.of(), new File("."));
 	}
 
 	public JavaTXCompiler(List<File> sources, List<File> contextPath, File outputPath) throws IOException, ClassNotFoundException {
-		this(sources, contextPath, outputPath, Optional.empty());
-	}
-
-	public JavaTXCompiler(List<File> sources, List<File> contextPath, File outputPath, Optional<String> unifyServer) throws IOException, ClassNotFoundException {
 		// ensure new default placeholder registry for tests
 		defaultClientPlaceholderRegistry = new PlaceholderRegistry();
+		NameGenerator.reset();
+		ASTToTargetAST.OBJECT = ASTFactory.createObjectType();
 
-		this.unifyServer = unifyServer;
 		var path = new ArrayList<>(contextPath);
 		if (contextPath.isEmpty()) {
 			// When no contextPaths are given, the working directory is the sources root
@@ -425,11 +425,14 @@ public class JavaTXCompiler {
 		 * Set<Set<UnifyPair>> ret = new HashSet<>(); for (Constraint<UnifyPair> y : x) { ret.add(new HashSet<>(y)); } return ret; }).collect(Collectors.toCollection(ArrayList::new))
 		 */;
 
-		if (unifyServer.isPresent()) {
+		if (ConsoleInterface.unifyServerUrl.isPresent()) {
 			UnifyResultModel urm = new UnifyResultModel(cons, finiteClosure);
 			UnifyContext context = new UnifyContext(logger, true, urm, usedTasks, placeholderRegistry);
-			SocketClient socketClient = new SocketClient(unifyServer.get());
-			return socketClient.execute(finiteClosure, cons, unifyCons, context);
+			SocketFuture<UnifyResultPacket> future = SocketClient.execute(
+				UnifyRequestPacket.create(finiteClosure, cons, unifyCons, context.placeholderRegistry())
+			);
+			SocketClient.execute(SetAutoclosePacket.create());
+			return future.get().getResultSet(context);
 		}
 		else if (resultmodel) {
 			/* UnifyResultModel Anfang */
@@ -669,7 +672,7 @@ public class JavaTXCompiler {
 			output = new FileOutputStream(outputFile);
 			output.write(bytecode);
 			output.close();
-			defaultLogger.info(name + ".class file generated");
+			defaultLogger.success(name + ".class file generated");
 		}
 	}
 

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

@@ -10,10 +10,10 @@ public class JavaTXServer {
 
   public JavaTXServer(int port) {
     this.socketServer = new SocketServer(port);
-    isRunning = true;
   }
 
   public void listen() {
+    isRunning = true;
     socketServer.start();
   }
 

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

@@ -1,6 +1,8 @@
 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;
@@ -14,8 +16,10 @@ 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;
@@ -31,43 +35,31 @@ public class SocketClient extends WebSocketClient {
 
   public static Logger logger = new Logger("SocketClient");
 
-  // use a latch to wait until the connection is closed by the remote host
-  private final CountDownLatch closeLatch = new CountDownLatch(1);
-  // temporarily: The received unify result
-  // TODO: replace with uuid and future system, such that responses can be mapped by a uuid to fulfill a Future
-  private UnifyResultPacket unifyResultPacket;
+  /**
+   * The singleton object
+   */
+  private static SocketClient socketClient = null;
 
-  public SocketClient(String url) {
+  /**
+   * 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
+      //SocketServer.perMessageDeflateDraft, // enable compression
       Map.of( // headers
         "packetProtocolVersion", SocketServer.packetProtocolVersion
       )
     );
-    // make sure, the url is in a valid format
+
+    // 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>");
     }
-  }
-
-  public SocketClient(String host, int port, boolean secure) {
-    this(String.format("%s://%s:%d/", secure ? "wss" : "ws", host, port));
-  }
-
-  /**
-   * The main method for connecting, requesting and waiting for the server to unify.
-   * This is synchronized to prevent multiple webSockets connections at the moment, but it is not called from any
-   * thread except the main thread right now and is not necessary at all, probably. Maybe remove it later
-   */
-  synchronized public List<ResultSet> execute(
-    FiniteClosure finiteClosure,
-    ConstraintSet<Pair> constraintSet,
-    ConstraintSet<UnifyPair> unifyConstraintSet,
-    UnifyContext context
-  ) throws JsonProcessingException {
 
     try {
       // wait for the connection to be set up
@@ -76,60 +68,108 @@ public class SocketClient extends WebSocketClient {
       if (this.getReadyState() != ReadyState.OPEN) {
         throw new RuntimeException("WebSocket Client could not connect to remote host at " + this.uri);
       }
-
-      // send the unify task request
-      UnifyRequestPacket packet = new UnifyRequestPacket(finiteClosure, constraintSet, unifyConstraintSet, context.placeholderRegistry());
-      String json = PacketContainer.serialize(packet);
-      this.send(json);
-
-      // block the thread, until the connection is closed by the remote host (usually after sending the results)
-      this.waitUntilClosed();
-      // wait for the connection to fully close
-      this.closeBlocking();
     } catch (InterruptedException exception) {
-      System.err.println("Server connection interrupted: " + exception);
-      this.notifyAll();
-      throw new RuntimeException("Aborted server connection", 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);
     }
 
-    // detect error cases, in which no error was thrown, but also no result was sent back from the server
-    if (this.unifyResultPacket == null) {
-      throw new RuntimeException("Did not receive server response but closed connection already");
-    }
+    return future;
+  }
 
-    return unifyResultPacket.getResultSet(context);
+  /**
+   * 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) {
-
-      try {
-        serverToClientPacket.onHandle(this.getConnection(), this);
-      } catch (Exception exception) {
-        this.closeLatch.countDown();
-        this.close();
-        throw exception;
-      }
-
+    if (!(packet instanceof IServerToClientPacket serverToClientPacket)) {
+      System.err.println("Received package of invalid type + " + packet.getClass().getName());
+      this.close();
       return;
     }
 
-    System.err.println("Received package of invalid type + " + packet.getClass().getName());
-    this.close();
+    serverToClientPacket.onHandle(this.getConnection(), this);
   }
 
-  public void setUnifyResultSets(UnifyResultPacket unifyResultPacket) {
-    this.unifyResultPacket = unifyResultPacket;
+  /**
+   * 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.info("Connected to server with status " + handshakedata.getHttpStatus());
+    logger.success("Connected to server with status " + handshakedata.getHttpStatus());
   }
 
   @Override
@@ -147,16 +187,16 @@ public class SocketClient extends WebSocketClient {
         (reason.isEmpty() ? "" : "and reason " + reason + " ") +
         "(closed by remote: " + remote + ")"
     );
-    this.closeLatch.countDown();
+
+    if (!this.responseFutures.isEmpty()) {
+      throw new RuntimeException("Server closed before all required tasks were answered");
+    }
   }
 
   @Override
   public void onError(Exception e) {
-    logger.error("Error: " + e.getMessage());
-    e.printStackTrace();
+    logger.exception(e);
+    throw new RuntimeException(e);
   }
 
-  public void waitUntilClosed() throws InterruptedException {
-    closeLatch.await();
-  }
 }

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

@@ -1,7 +1,6 @@
 package de.dhbwstuttgart.server;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
-import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.server.packet.ErrorPacket;
 import de.dhbwstuttgart.server.packet.IClientToServerPacket;
 import de.dhbwstuttgart.server.packet.IPacket;
@@ -10,11 +9,13 @@ import de.dhbwstuttgart.server.packet.PacketContainer;
 import de.dhbwstuttgart.util.Logger;
 import java.net.InetSocketAddress;
 import java.util.Collections;
-import java.util.Objects;
 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;
@@ -22,67 +23,83 @@ 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.DefaultWebSocketServerFactory;
 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 server version and client version do not match.
+   * This will prevent errors when the server version and client version do not match.
    */
   public static final String packetProtocolVersion = "1";
 
-  /**
-   * Draft object for enabling the perMessageDeflate extension for more packet compression
-   */
-  public static final Draft perMessageDeflateDraft = new Draft_6455(new PerMessageDeflateExtension());
+  // 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), Collections.singletonList(perMessageDeflateDraft));
+    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)) {
-      try {
-        ErrorPacket errorPacket = ErrorPacket.create(
-          "Mismatch in packet protocol version! Client (you): " + ppv + " and Server (me): " + packetProtocolVersion,
-          true
-        );
-        webSocket.send(PacketContainer.serialize(errorPacket));
-      }
-      catch (JsonProcessingException exception) {
-        System.err.println("Failed to serialize json: " + exception);
-      }
+      this.sendError(webSocket,
+        "Mismatch in packet protocol version! Client (you): \"" + ppv + "\" and Server (me): \"" + packetProtocolVersion + "\"",
+        true
+      );
       webSocket.close(1);
       return;
     }
 
-
-    SocketData socketData = new SocketData(UUID.randomUUID().toString());
-    webSocket.setAttachment(socketData);
+    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
-      try (ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor()) {
-        Runnable task = () -> {
-          if (webSocket.<SocketData>getAttachment().unhandledTasks.get() == 0 || !webSocket.isOpen()) {
+      final int secondsUntilTimeout = 10;
+      timeoutExecutor.schedule(() -> {
+          if (webSocket.<SocketData>getAttachment().totalTasks.get() > 0 || !webSocket.isOpen()) {
             return;
           }
-          sendMessage(webSocket, "No task received after 10 seconds. Closing connection...");
+          sendMessage(webSocket, "No task received after " + secondsUntilTimeout + " seconds. Closing connection...");
           webSocket.close();
-        };
-        executor.schedule(task, 10, TimeUnit.SECONDS);
-        executor.shutdown();
-      }
+        },
+        secondsUntilTimeout,
+        TimeUnit.SECONDS
+      );
 
       // and finally, when your program wants to exit
     } catch (Exception e) {
@@ -112,20 +129,22 @@ public class SocketServer extends WebSocketServer {
       this.onPacketReceived(webSocket, reconstructedPacket);
     } catch (JsonProcessingException e) {
       logger.exception(e);
-      this.log("Error on processing incoming package: " + e.getMessage(), webSocket);
+      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);
-    log(e.getMessage(), webSocket);
-    webSocket.close();
   }
 
   @Override
   public void onStart() {
-    logger.info("Websocket server started on port " + this.getPort());
+    logger.success("Websocket server started on port " + this.getPort());
   }
 
   /**
@@ -133,8 +152,7 @@ public class SocketServer extends WebSocketServer {
    */
   public void sendMessage(WebSocket webSocket, String text) {
     try {
-      MessagePacket message = new MessagePacket();
-      message.message = text;
+      MessagePacket message = MessagePacket.create(text);
       webSocket.send(PacketContainer.serialize(message));
     } catch (Exception e) {
       System.err.println("Failed to send message: " + text);
@@ -145,33 +163,31 @@ public class SocketServer extends WebSocketServer {
   /**
    * A shorthand method for sending error messages to the client
    */
-  public void sendError(WebSocket webSocket, String text) {
+  public void sendError(WebSocket webSocket, String text, boolean isFatal) {
     try {
-      ErrorPacket error = new ErrorPacket();
-      error.error = text;
+      ErrorPacket error = ErrorPacket.create(text, isFatal);
       webSocket.send(PacketContainer.serialize(error));
     } catch (Exception e) {
       logger.exception(e);
-      log("Failed to send error: " + text, webSocket);
+      log(webSocket, "Failed to send error: " + text);
     }
   }
 
   /**
-   *  The server-side implementation on how to handle certain packets when received
+   * 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 amount of tasks per connection
-    final int maxTasks = 100;
-    if (socketData.totalTasks.get() >= maxTasks) {
-      sendError(webSocket, "Exceeded the maximum amount of " + maxTasks + " tasks per session");
+    // 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)) {
+    // 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;
     }
@@ -180,22 +196,24 @@ public class SocketServer extends WebSocketServer {
     socketData.unhandledTasks.incrementAndGet();
     socketData.totalTasks.incrementAndGet();
 
-    // add the packet to the queue, so it can be started by the worker
+    // add the packet to the queue so it can be started by the worker
     CompletableFuture.runAsync(() -> {
       clientToServerPacket.onHandle(webSocket, this);
-
-      // if the websocket has 0 unhandled Tasks, close the connection
       int remainingUnhandledTasks = socketData.unhandledTasks.decrementAndGet();
-      if (remainingUnhandledTasks <= 0) {
-        sendMessage(webSocket, "All requested tasks finished! Closing connection...");
-        webSocket.close();
+
+      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(String msg, WebSocket webSocket) {
-    SocketData socketData = webSocket == null ? new SocketData("???") : webSocket.getAttachment();
-    logger.info("["+socketData.id+"] " + msg);
+  public void log(WebSocket webSocket, String msg) {
+    String socketId = (webSocket == null) ? "???" : webSocket.<SocketData>getAttachment().id;
+    logger.info("[" + socketId + "] " + msg);
   }
 
   /**
@@ -207,9 +225,11 @@ public class SocketServer extends WebSocketServer {
     public final String id;
     public final AtomicInteger unhandledTasks = new AtomicInteger(0);
     public final AtomicInteger totalTasks = new AtomicInteger(0);
+    public boolean closeIfNoTasksLeft = false;
 
-    public SocketData(String id) {
-      this.id = id;
+    public SocketData(WebSocket webSocket) {
+      this.id = UUID.randomUUID().toString();
+      webSocket.setAttachment(this);
     }
   }
 }

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

@@ -2,6 +2,7 @@ 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;
@@ -10,7 +11,7 @@ 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, IServerToClientPacket {
+public class DebugPacket implements IClientToServerPacket.Void, IServerToClientPacket {
 
   public SerialUUID a1;
   public SerialUUID a2;
@@ -22,9 +23,13 @@ public class DebugPacket implements IClientToServerPacket, IServerToClientPacket
   public SerialValue<?> d2;
 
   @JsonIgnore
-  public void onHandle(WebSocket webSocket, SocketClient socketServer) {}
+  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

@@ -2,16 +2,17 @@ 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 IClientToServerPacket, IServerToClientPacket {
+public class ErrorPacket implements IServerToClientPacket {
 
   /**
-   * The error endpoint for messages from the server, that should be logged out outputted
+   * 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;
@@ -27,15 +28,9 @@ public class ErrorPacket implements IClientToServerPacket, IServerToClientPacket
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketClient socketClient) {
-    SocketClient.logger.error("SocketError: " + this.error);
+    SocketClient.logger.exception(new RuntimeException(this.error));
     if (this.isFatal) {
-      throw new RuntimeException("Received fatal error from server: " + this.error);
+      socketClient.close(1, "Received fatal error from server");
     }
   }
-
-  @JsonIgnore
-  public void onHandle(WebSocket webSocket, SocketServer socketServer) {
-    socketServer.log("SocketError: " + this.error, webSocket);
-  }
-
 }

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

@@ -1,12 +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;
 
-public interface IClientToServerPacket extends IPacket {
+/**
+ * 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/InvalidPacket.java

@@ -2,13 +2,14 @@ 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
+ * A fallback packet that is generated if the received JSON could not be mapped to an existing package
  */
-public class InvalidPacket implements IClientToServerPacket, IServerToClientPacket {
+public class InvalidPacket implements IClientToServerPacket.Void, IServerToClientPacket {
 
   /**
    * If available, the error that caused this package to appear
@@ -18,12 +19,17 @@ public class InvalidPacket implements IClientToServerPacket, IServerToClientPack
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketClient socketClient) {
-    System.err.println("[socket] " + "InvalidPacket: " + this.error);
+    SocketClient.logger.error("InvalidPacket: " + this.error);
   }
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketServer socketServer) {
-    socketServer.log("InvalidPacket: " + this.error, webSocket);
+    socketServer.log(webSocket, "InvalidPacket: " + this.error);
+  }
+
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
   }
 
 }

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

@@ -2,16 +2,17 @@ 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, IServerToClientPacket {
+public class MessagePacket implements IClientToServerPacket.Void, IServerToClientPacket {
 
   /**
-   * The informational message from the server, that should be logged out outputted
+   * The informational message from the server that should be logged out outputted
    */
   public String message;
 
@@ -29,7 +30,11 @@ public class MessagePacket implements IClientToServerPacket, IServerToClientPack
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketServer socketServer) {
-    socketServer.log(this.message, webSocket);
+    socketServer.log(webSocket, this.message);
   }
 
+  @JsonIgnore
+  public SocketFuture<IServerToClientPacket> getFuture() {
+    return SocketFuture.completedFuture();
+  }
 }

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

@@ -25,13 +25,14 @@ public class PacketContainer {
   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
+   * @return The JSON representation of the packet
    */
   public static String serialize(IPacket packet) throws JsonProcessingException {
     objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
@@ -47,7 +48,11 @@ public class PacketContainer {
       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);
   }
@@ -76,6 +81,8 @@ public class PacketContainer {
         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");

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

@@ -1,6 +1,9 @@
 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;
@@ -20,18 +23,16 @@ 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.io.FileWriter;
-import java.io.IOException;
-import java.io.Writer;
 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 {
+public class UnifyRequestPacket implements IClientToServerPacket<UnifyResultPacket> {
 
   public SerialMap finiteClosure;
   public SerialMap constraintSet;
@@ -39,30 +40,33 @@ public class UnifyRequestPacket implements IClientToServerPacket {
   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 UnifyRequestPacket() {}
-
-  public UnifyRequestPacket(
+  public static UnifyRequestPacket create(
     FiniteClosure finiteClosure,
     ConstraintSet<Pair> constraintSet,
     ConstraintSet<UnifyPair> unifyConstraintSet,
     PlaceholderRegistry placeholderRegistry
   ) {
-    // store contraint and finite closure
-    this.finiteClosure = finiteClosure.toSerial(keyStorage);
-    this.constraintSet = constraintSet.toSerial(keyStorage);
-    this.unifyConstraintSet = unifyConstraintSet.toSerial(keyStorage);
+    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(keyStorage);
-    this.placeholders = serialRegistry.getValue("ph");
-    this.factoryplaceholders = serialRegistry.getList("factoryPh").assertListOfMaps();
+    var serialRegistry = placeholderRegistry.toSerial(packet.keyStorage);
+    packet.placeholders = serialRegistry.getValue("ph");
+    packet.factoryplaceholders = serialRegistry.getList("factoryPh").assertListOfMaps();
     // store referenced objects separately
-    this.serialKeyStorage = keyStorage.toSerial(keyStorage);
+    packet.serialKeyStorage = packet.keyStorage.toSerial(packet.keyStorage);
+    packet.logLevel = ConsoleInterface.logLevel.getValue();
+    return packet;
   }
 
 
@@ -95,15 +99,22 @@ public class UnifyRequestPacket implements IClientToServerPacket {
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketServer socketServer) {
     socketServer.sendMessage(webSocket, "You requested a unify! Please wait until I calculated everything...");
-    SocketServer.logger.info("Client " + webSocket.<SocketServer.SocketData>getAttachment().id + " requested a unification. Starting now...");
+    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);
 
-      var unifyContext = new UnifyContext(Logger.NULL_LOGGER, true,
-        new UnifyResultModel(new ConstraintSet<>(), new FiniteClosure(new HashSet<>(), Logger.NULL_LOGGER, placeholderRegistry)),
+      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
       );
 
@@ -130,17 +141,24 @@ public class UnifyRequestPacket implements IClientToServerPacket {
 
       var resultSets = resultListener.getResults();
 
-      SocketServer.logger.info("Finished unification for client " + webSocket.<SocketServer.SocketData>getAttachment().id);
+      socketServer.log(webSocket, "Finished unification");
       socketServer.sendMessage(webSocket, "Unification finished. Found " + resultSets.size() + " result sets");
 
       if (webSocket.isOpen()) {
-        UnifyResultPacket resultPacket = UnifyResultPacket.create(resultSets);
+        UnifyResultPacket resultPacket = UnifyResultPacket.create(resultSets, futureId);
         webSocket.send(PacketContainer.serialize(resultPacket));
       }
     } catch (Exception e) {
       SocketServer.logger.exception(e);
-      socketServer.log(e.getMessage(), webSocket);
+      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

@@ -18,12 +18,14 @@ public class UnifyResultPacket implements IServerToClientPacket {
 
   public SerialList<ISerialNode> results;
   public SerialMap keyStorage;
+  public String futureId;
 
-  public static UnifyResultPacket create(List<ResultSet> resultSets) {
+  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;
   }
 
@@ -35,8 +37,8 @@ public class UnifyResultPacket implements IServerToClientPacket {
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketClient socketClient) {
-    SocketClient.logger.info("[socket] Received unify result");
-    socketClient.setUnifyResultSets(this);
+    SocketClient.logger.info("Received unify result");
+    socketClient.completeResponseFuture(futureId, this);
   }
 
 

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

@@ -1,6 +1,5 @@
 package de.dhbwstuttgart.target.generate;
 
-import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.exceptions.DebugException;
 import de.dhbwstuttgart.exceptions.NotImplementedException;
 import de.dhbwstuttgart.parser.SyntaxTreeGenerator.AssignToLocal;
@@ -16,6 +15,7 @@ import de.dhbwstuttgart.target.tree.type.*;
 
 import java.lang.reflect.Modifier;
 import java.util.*;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
@@ -219,6 +219,22 @@ public class StatementToTargetExpression implements ASTVisitor {
         if (methodCall.receiver instanceof ExpressionReceiver expressionReceiver && expressionReceiver.expr instanceof This) {
             if (receiverClass == null) throw new DebugException("Class " + receiverName + " does not exist!");
             var thisMethod = converter.findMethod(receiverClass, methodCall.name, signature);
+            if (thisMethod.isEmpty()) {
+                Target.logger.error("Expected: " + receiverClass.getClassName() + "." + methodCall.name + "(" +
+                  signature.stream().map(TargetType::toSignature).collect(Collectors.joining())+ ")" );
+
+                AtomicBoolean hasM = new AtomicBoolean(false);
+                receiverClass.getMethods().forEach(m -> {
+                    if (Objects.equals(m.getName(), methodCall.name)) {
+                        hasM.set(true);
+                        Target.logger.error("But only has: " + m.name + "(" +
+                          m.getParameterList().getFormalparalist().stream().map(t -> t.getType().toString()).collect(Collectors.joining())+ ")" );
+                    }
+                });
+                if (!hasM.get())
+                    Target.logger.error("But does not contain method at all");
+            }
+
             ClassOrInterface finalReceiverClass = receiverClass;
             foundMethod = thisMethod.orElseGet(() -> findMethod(finalReceiverClass.getSuperClass().getName(), methodCall.name, signature).orElseThrow());
         } else if (!isFunNType) {

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

@@ -37,6 +37,10 @@ public class Constraint<A extends IConstraintElement> extends HashSet<A> impleme
     super();
   }
 
+  public Constraint(int initialCapacity) {
+    super(initialCapacity);
+  }
+
   public Constraint(boolean isInherited, boolean isImplemented) {
     this.isInherited = isInherited;
     this.isImplemented = isImplemented;
@@ -77,6 +81,14 @@ public class Constraint<A extends IConstraintElement> extends HashSet<A> impleme
     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

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

@@ -5,6 +5,7 @@ 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;
@@ -29,7 +30,7 @@ public class ResultSet implements ISerializableData {
 
   public ResultSet(Set<ResultPair> set) {
     this.results = set;
-    this.genIns = new HashSet<>();
+    this.genIns = TypeUnifyTaskHelper.getPresizedHashSet(results.size());
     results.forEach(x -> {
       if (x instanceof PairTPHsmallerTPH) {
         this.genIns.add(x);

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)));

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

@@ -2,6 +2,7 @@
 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;
 
@@ -117,17 +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);
     }
@@ -142,7 +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);
@@ -190,7 +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);
@@ -200,7 +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);
@@ -213,7 +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);
@@ -283,8 +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())));
@@ -292,7 +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())));
@@ -300,7 +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())));
@@ -308,7 +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())));
@@ -316,7 +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())));
@@ -324,7 +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())));
@@ -339,7 +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())));
@@ -347,7 +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);
@@ -733,7 +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;
     }
 
@@ -746,8 +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();
@@ -883,13 +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);
+                  }
                 }
             });
 
@@ -905,7 +908,7 @@ 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;
 

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

@@ -1,6 +1,7 @@
 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;
@@ -8,7 +9,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
  * An intermediate class for the recursive steps of the TypeUnifyTask:
- * This allows to cancel parts of the recursion tree, instead of only  the whole execution as before. But in
+ * 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>
@@ -16,20 +17,19 @@ import java.util.concurrent.atomic.AtomicBoolean;
 public abstract class CancellableTask<T> extends RecursiveTask<T> {
 
   private final AtomicBoolean executionCancelled = new AtomicBoolean(false);
-  private final List<CancellableTask<?>> childTasks = new ArrayList<>();
+  private final List<CancellableTask<?>> childTasks = new LinkedList<>();
   private CancellableTask<?> parentTask = null;
 
   /**
-   * Set the execution for this task and all its (recursive) children to be cancelled
+   * Set the execution for this task and all its (recursive) children to be canceled
    */
   protected void cancelExecution() {
-    // is this branch already cancelled? Then do nothing
-    if (this.executionCancelled.get()) return;
-    executionCancelled.set(true);
+    // is this branch already canceled? Then do nothing
+    if (this.executionCancelled.getAndSet(true)) return;
     this.cancelChildExecution();
   }
 
-  public void cancelChildExecution() {
+  private void cancelChildExecution() {
     synchronized (this.childTasks) {
       for (var childTask : childTasks) {
         // no need to cancel a branch that is already finished
@@ -40,6 +40,24 @@ public abstract class CancellableTask<T> extends RecursiveTask<T> {
     }
   }
 
+  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();
@@ -48,6 +66,12 @@ public abstract class CancellableTask<T> extends RecursiveTask<T> {
     }
   }
 
+  public void cancelYoungerSiblingTasks() {
+    if (this.parentTask != null) {
+      this.parentTask.cancelChildExecutionAfter(this);
+    }
+  }
+
   public Boolean isExecutionCancelled() {
     return executionCancelled.get();
   }
@@ -55,6 +79,9 @@ public abstract class CancellableTask<T> extends RecursiveTask<T> {
   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) {

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/RuleSet.java

@@ -6,6 +6,7 @@ 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;
@@ -648,15 +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))
@@ -668,12 +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;
@@ -691,19 +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

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

@@ -45,7 +45,7 @@ public class TypeUnify2Task extends TypeUnifyTask {
                */
     //writeLog("xxx");
     //noOfThread--;
-    if (this.myIsCancelled()) {
+    if (this.isExecutionCancelled()) {
       return CompletableFuture.completedFuture(new HashSet<>());
     } else {
       return res;

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

@@ -3,6 +3,7 @@ package de.dhbwstuttgart.typeinference.unify;
 
 import de.dhbwstuttgart.exceptions.TypeinferenceException;
 import de.dhbwstuttgart.parser.NullToken;
+import de.dhbwstuttgart.server.ServerTaskLogger;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
 import de.dhbwstuttgart.typeinference.unify.cartesianproduct.VarianceCase;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
@@ -26,11 +27,7 @@ import de.dhbwstuttgart.typeinference.unify.model.WildcardType;
 import de.dhbwstuttgart.util.Logger;
 import de.dhbwstuttgart.util.Pair;
 import de.dhbwstuttgart.util.Tuple;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.io.OutputStreamWriter;
 import java.io.Serial;
-import java.io.Writer;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -49,7 +46,6 @@ import java.util.concurrent.RecursiveTask;
 import java.util.function.BiFunction;
 import java.util.function.BinaryOperator;
 import java.util.stream.Collectors;
-import org.apache.commons.io.output.NullOutputStream;
 
 
 /**
@@ -117,8 +113,6 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
   public static int noShortendElements;
   public static int noou = 0;
 
-  boolean myIsCanceled = false;
-
   public TypeUnifyTask(UnifyContext context) {
     this.context = context.newWithLogger(Logger.NULL_LOGGER);
     rules = new RuleSet(context.placeholderRegistry());
@@ -155,7 +149,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     this.fc = fc;
     this.oup = new OrderingUnifyPair(fc, context);
 
-    this.context = context.newWithLogger(
+    this.context = (context.logger() instanceof ServerTaskLogger) ? context : context.newWithLogger(
       Logger.forFile(
         System.getProperty("user.dir") + "/logFiles/" + "Thread",
         "Unify"
@@ -213,13 +207,6 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 		}		
 }
 */
-  void myCancel(boolean b) {
-    myIsCanceled = true;
-  }
-
-  public boolean myIsCancelled() {
-    return myIsCanceled;
-  }
 
   public CompletableFuture<Set<Set<UnifyPair>>> compute() {
     if (one) {
@@ -249,7 +236,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         throw new TypeinferenceException("Unresolved constraints: " + res, new NullToken()); //return new HashSet<>();
       }
 
-      if (this.myIsCancelled()) {
+      if (this.isExecutionCancelled()) {
         return new HashSet<>();
       }
 
@@ -286,7 +273,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     //.collect(Collectors.toCollection(HashSet::new)));
 
-    if (this.myIsCancelled()) {
+    if (this.isExecutionCancelled()) {
       return CompletableFuture.completedFuture(new HashSet<>());
     }
 
@@ -315,14 +302,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     /*
      * Occurs-Check durchfuehren
      */
-    Set<UnifyPair> ocurrPairs = eq.stream().filter(x -> {
-        UnifyType lhs, rhs;
-        return (lhs = x.getLhsType()) instanceof PlaceholderType
-          && !((rhs = x.getRhsType()) instanceof PlaceholderType)
-          && rhs.getTypeParams().occurs((PlaceholderType) lhs);
-      })
-      .peek(UnifyPair::setUndefinedPair)
-      .collect(Collectors.toCollection(HashSet::new));
+    Set<UnifyPair> ocurrPairs = TypeUnifyTaskHelper.occursCheck(eq);
 
     Set<UnifyPair> finalOcurrPairs = ocurrPairs;
     context.logger().debug(() -> "ocurrPairs: " + finalOcurrPairs);
@@ -346,14 +326,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       /* In commit dfd91b5f8b7fca1cb5f302eec4b0ba3330271c9b eingefuegt ANFANG */
       Set<UnifyPair> occurcheck = new HashSet<>(eq0);
       occurcheck.removeAll(eq0Prime);
-      ocurrPairs = occurcheck.stream().filter(x -> {
-          UnifyType lhs, rhs;
-          return (lhs = x.getLhsType()) instanceof PlaceholderType
-            && !((rhs = x.getRhsType()) instanceof PlaceholderType)
-            && rhs.getTypeParams().occurs((PlaceholderType) lhs);
-        })
-        .peek(UnifyPair::setUndefinedPair)
-        .collect(Collectors.toCollection(HashSet::new));
+      ocurrPairs = TypeUnifyTaskHelper.occursCheck(occurcheck);
       Set<UnifyPair> finalOcurrPairs1 = ocurrPairs;
       context.logger().debug(() -> "ocurrPairs: " + finalOcurrPairs1);
       if (!ocurrPairs.isEmpty()) {
@@ -490,7 +463,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     //		.collect(Collectors.toCollection(HashSet::new));
     //Muss auskommentiert werden, wenn computeCartesianRecursive ENDE
 
-    if (this.myIsCancelled()) {
+    if (this.isExecutionCancelled()) {
       return CompletableFuture.completedFuture(new HashSet<>());
     }
 
@@ -767,7 +740,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     // Ergebnisvariable für die parallele Verabeitung: Tupel aus
     // - forkOrig result : currentThreadResult (frueher "res")
     // - fork results : forkResults (frueher "add_res")
-    CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> parallelResultDataFuture;
+    CompletableFuture<VarianceCase.ComputationResults> parallelResultDataFuture;
+
 
     if (parallel) {
       parallelResultDataFuture = varianceCase.computeParallel(
@@ -778,13 +752,16 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       // same as variance = 0
       elems.add(varianceCase.a); //PL 2019-01-16 muss das wirklich hin steht schon in Zeile 859 ja braucht man siehe Zeile 859
       parallelResultDataFuture =  this.unify2(elems, eq, oderConstraints, fc, false, rekTiefe, new HashSet<>(methodSignatureConstraint))
-        .thenApply(currentThreadResult -> new Tuple<>(currentThreadResult, new HashSet<>()));
+        .thenApply(VarianceCase.ComputationResults::new);
     }
 
+    if (this.isExecutionCancelled()) {
+      return CompletableFuture.completedFuture(new HashSet<>());
+    }
 
     return parallelResultDataFuture.thenCompose(parallelResultData -> {
-      Set<Set<UnifyPair>> currentThreadResult = parallelResultData.getFirst();
-      Set<Set<Set<UnifyPair>>> forkResults = parallelResultData.getSecond();
+      Set<Set<UnifyPair>> currentThreadResult = parallelResultData.mainResult;
+      Set<Set<Set<UnifyPair>>> forkResults = parallelResultData.forkResults;
 
       Set<Set<UnifyPair>> result = prevResult;
       List<Set<UnifyPair>> nextSetAsList = prevNextSetAsList;
@@ -848,17 +825,6 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
       if (parallel) {
         for (Set<Set<UnifyPair>> par_res : forkResults) {
-
-          if (variance == 0) {
-            if (!result.isEmpty() && !isUndefinedPairSetSet(currentThreadResult)) {
-              return CompletableFuture.completedFuture(result);
-            }
-            else {
-              result.addAll(par_res);
-              continue;
-            }
-          }
-
           if (!isUndefinedPairSetSet(par_res) && isUndefinedPairSetSet(result)) {
             //wenn korrektes Ergebnis gefunden alle Fehlerfaelle loeschen
             result = par_res;
@@ -892,7 +858,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         // Iterator<Set<UnifyPair>> nextSetasListIt = new ArrayList<>(nextSetAsList).iterator();
         boolean shouldBreak = varianceCase.eraseInvalidSets(rekTiefe, aParDef, nextSetAsList);
         if (shouldBreak) {
-          //this.cancelChildExecution();
+          // this.cancelYoungerSiblingTasks();
           return CompletableFuture.completedFuture(result);
         }
 
@@ -1745,8 +1711,9 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         aa.putAll(b);
         return aa;
       };
-      HashMap<PlaceholderType, PlaceholderType> hm = x.getInvolvedPlaceholderTypes().stream()
-        .reduce(new HashMap<PlaceholderType, PlaceholderType>(),
+      var involvedPlaceholderTypes = x.getInvolvedPlaceholderTypes();
+      HashMap<PlaceholderType, PlaceholderType> hm = involvedPlaceholderTypes.stream()
+        .reduce(TypeUnifyTaskHelper.getPresizedHashMap(involvedPlaceholderTypes.size()),
           (aa, b) -> {
             aa.put(b, PlaceholderType.freshPlaceholder(context.placeholderRegistry()));
             return aa;

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

@@ -5,6 +5,7 @@ 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;
@@ -185,4 +186,36 @@ public class TypeUnifyTaskHelper {
       .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/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

@@ -1,6 +1,5 @@
 package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
 
-import de.dhbwstuttgart.exceptions.UnifyCancelException;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
 import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
 import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
@@ -17,11 +16,11 @@ import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.stream.Collectors;
 
-public class Variance1Case extends VarianceCase {
+public class ContravarianceCase extends VarianceCase {
 
   protected final int variance = 1;
 
-  protected Variance1Case(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+  protected ContravarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
     super(isOderConstraint, typeUnifyTask, context);
   }
 
@@ -37,7 +36,7 @@ public class Variance1Case extends VarianceCase {
     if (this.isOderConstraint) {
       nextSetasListOderConstraints.add(((Constraint<UnifyPair>) a).getExtendConstraint());
     }
-    context.logger().debug("nextSetasListOderConstraints 1: " + nextSetasListOderConstraints);
+    context.logger().debug(() -> "nextSetasListOderConstraints 1: " + nextSetasListOderConstraints);
 
     //Alle maximale Elemente in nextSetasListRest bestimmen
     //nur für diese wird parallele Berechnung angestossen.
@@ -49,7 +48,7 @@ public class Variance1Case extends VarianceCase {
 
 
   @Override
-  public CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> computeParallel(
+  public CompletableFuture<ComputationResults> computeParallel(
     Set<Set<UnifyPair>> elems,
     Set<UnifyPair> eq,
     List<Set<Constraint<UnifyPair>>> oderConstraints,
@@ -61,10 +60,6 @@ public class Variance1Case extends VarianceCase {
     Set<Set<UnifyPair>> result,
     Set<Set<UnifyPair>> aParDef
   ) {
-    CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> resultValues = CompletableFuture.completedFuture(new Tuple<>(
-      new HashSet<>(), new HashSet<>()
-    ));
-
     Set<UnifyPair> newEqOrig = new HashSet<>(eq);
     Set<Set<UnifyPair>> newElemsOrig = new HashSet<>(elems);
     List<Set<Constraint<UnifyPair>>> newOderConstraintsOrig = new ArrayList<>(oderConstraints);
@@ -75,16 +70,16 @@ public class Variance1Case extends VarianceCase {
     typeUnifyTask.addChildTask(forkOrig);
     // schedule compute() on another thread
     CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
-    resultValues = resultValues.thenCombine(forkOrigFuture,
-      (prevResults, currentThreadResult) -> {
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply(
+      (currentThreadResult) -> {
         forkOrig.context.logger().debug("final Orig 1");
         forkOrig.closeLogFile();
-        return new Tuple<>(currentThreadResult, prevResults.getSecond());
+        return new ComputationResults(currentThreadResult);
       });
 
     //forks.add(forkOrig);
-    if (typeUnifyTask.myIsCancelled()) {
-      throw new UnifyCancelException();
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return CompletableFuture.completedFuture(new ComputationResults());
     }
     /* FORK ENDE */
 
@@ -114,12 +109,12 @@ public class Variance1Case extends VarianceCase {
       CompletableFuture<Set<Set<UnifyPair>>> forkFuture = CompletableFuture.supplyAsync(fork::compute, context.executor()).thenCompose(f -> f);
       resultValues = resultValues.thenCombine(forkFuture,
         (prevResults, fork_res) -> {
-          if (typeUnifyTask.myIsCancelled()) {
-            throw new UnifyCancelException();
+          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.getSecond().add(fork_res);
+          prevResults.addForkResult(fork_res);
           if (!typeUnifyTask.isUndefinedPairSetSet(fork_res)) {
             aParDef.add(fork.getNextSetElement());
           }
@@ -129,8 +124,8 @@ public class Variance1Case extends VarianceCase {
         }
       );
 
-      if (typeUnifyTask.myIsCancelled()) {
-        throw new UnifyCancelException();
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return CompletableFuture.completedFuture(new ComputationResults());
       }
     }
 

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

@@ -1,6 +1,5 @@
 package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
 
-import de.dhbwstuttgart.exceptions.UnifyCancelException;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
 import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
 import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
@@ -17,11 +16,11 @@ import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.stream.Collectors;
 
-public class VarianceM1Case extends VarianceCase {
+public class CovarianceCase extends VarianceCase {
 
   protected final int variance = -1;
 
-  protected VarianceM1Case(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+  protected CovarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
     super(isOderConstraint, typeUnifyTask, context);
   }
 
@@ -49,7 +48,7 @@ public class VarianceM1Case extends VarianceCase {
 
 
   @Override
-  public CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> computeParallel(
+  public CompletableFuture<ComputationResults> computeParallel(
     Set<Set<UnifyPair>> elems,
     Set<UnifyPair> eq,
     List<Set<Constraint<UnifyPair>>> oderConstraints,
@@ -61,10 +60,6 @@ public class VarianceM1Case extends VarianceCase {
     Set<Set<UnifyPair>> result,
     Set<Set<UnifyPair>> aParDef
   ) {
-    CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> resultValues = CompletableFuture.completedFuture(new Tuple<>(
-      new HashSet<>(), new HashSet<>()
-    ));
-
     Set<UnifyPair> newEqOrig = new HashSet<>(eq);
     Set<Set<UnifyPair>> newElemsOrig = new HashSet<>(elems);
     List<Set<Constraint<UnifyPair>>> newOderConstraintsOrig = new ArrayList<>(oderConstraints);
@@ -75,16 +70,16 @@ public class VarianceM1Case extends VarianceCase {
     typeUnifyTask.addChildTask(forkOrig);
     // schedule compute() on another thread
     CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
-    resultValues = resultValues.thenCombine(forkOrigFuture,
-      (prevResults, currentThreadResult) -> {
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply(
+      (currentThreadResult) -> {
         forkOrig.context.logger().debug("final Orig -1");
         forkOrig.closeLogFile();
-        return new Tuple<>(currentThreadResult, prevResults.getSecond());
+        return new ComputationResults(currentThreadResult);
       });
 
     //forks.add(forkOrig);
-    if (typeUnifyTask.myIsCancelled()) {
-      throw new UnifyCancelException();
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return resultValues;
     }
     /* FORK ENDE */
 
@@ -115,12 +110,12 @@ public class VarianceM1Case extends VarianceCase {
       CompletableFuture<Set<Set<UnifyPair>>> forkFuture = CompletableFuture.supplyAsync(fork::compute, context.executor()).thenCompose(f -> f);
       resultValues = resultValues.thenCombine(forkFuture,
         (prevResults, fork_res) -> {
-          if (typeUnifyTask.myIsCancelled()) {
-            throw new UnifyCancelException();
+          if (typeUnifyTask.isExecutionCancelled()) {
+            return prevResults;
           }
           context.logger().debug(() -> "fork_res: " + fork_res.toString());
           context.logger().debug(() -> Boolean.valueOf((typeUnifyTask.isUndefinedPairSetSet(fork_res))).toString());
-          prevResults.getSecond().add(fork_res);
+          prevResults.addForkResult(fork_res);
           if (!typeUnifyTask.isUndefinedPairSetSet(fork_res)) {
             aParDef.add(fork.getNextSetElement());
           }
@@ -130,8 +125,8 @@ public class VarianceM1Case extends VarianceCase {
         }
       );
 
-      if (typeUnifyTask.myIsCancelled()) {
-        throw new UnifyCancelException();
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return resultValues;
       }
     }
 

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

@@ -1,6 +1,5 @@
 package de.dhbwstuttgart.typeinference.unify.cartesianproduct;
 
-import de.dhbwstuttgart.exceptions.UnifyCancelException;
 import de.dhbwstuttgart.typeinference.constraints.Constraint;
 import de.dhbwstuttgart.typeinference.unify.TypeUnify2Task;
 import de.dhbwstuttgart.typeinference.unify.TypeUnifyTask;
@@ -15,11 +14,12 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 
-public class Variance2Case extends VarianceCase {
+public class InvarianceOrConstraintCase extends VarianceCase {
 
+  // either for invariance or for oderConstraints
   protected final int variance = 2;
 
-  protected Variance2Case(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+  protected InvarianceOrConstraintCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
     super(isOderConstraint, typeUnifyTask, context);
   }
 
@@ -37,7 +37,7 @@ public class Variance2Case extends VarianceCase {
 
 
   @Override
-  public CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> computeParallel(
+  public CompletableFuture<ComputationResults> computeParallel(
     Set<Set<UnifyPair>> elems,
     Set<UnifyPair> eq,
     List<Set<Constraint<UnifyPair>>> oderConstraints,
@@ -49,8 +49,6 @@ public class Variance2Case extends VarianceCase {
     Set<Set<UnifyPair>> result,
     Set<Set<UnifyPair>> aParDef
   ) {
-    CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> resultValuesFuture;
-
     context.logger().debug("var2einstieg");
     Set<TypeUnify2Task> forks = new HashSet<>();
     Set<UnifyPair> newEqOrig = new HashSet<>(eq);
@@ -62,13 +60,14 @@ public class Variance2Case extends VarianceCase {
     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);
-    resultValuesFuture = forkOrigFuture.thenApply((currentThreadResult) -> {
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply((currentThreadResult) -> {
       forkOrig.context.logger().debug("final Orig 2");
       forkOrig.closeLogFile();
-      return new Tuple<>(currentThreadResult, new HashSet<>());
+      return new ComputationResults(currentThreadResult);
     });
-    if (typeUnifyTask.myIsCancelled()) {
-      throw new UnifyCancelException();
+
+    if (typeUnifyTask.isExecutionCancelled()) {
+      return resultValues;
     }
     /* FORK ENDE */
 
@@ -92,26 +91,22 @@ public class Variance2Case extends VarianceCase {
       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);
-      resultValuesFuture = resultValuesFuture.thenCombine(forkFuture, (resultValues, fork_res) -> {
-        if (typeUnifyTask.myIsCancelled()) {
-          throw new UnifyCancelException();
+      resultValues = resultValues.thenCombine(forkFuture, (prevResults, fork_res) -> {
+        if (typeUnifyTask.isExecutionCancelled()) {
+          return prevResults;
         }
-        resultValues.getSecond().add(fork_res);
+        prevResults.addForkResult(fork_res);
         fork.context.logger().debug("final 2");
         fork.closeLogFile();
-        return resultValues;
+        return prevResults;
       });
 
-      if (typeUnifyTask.myIsCancelled()) {
-        throw new UnifyCancelException();
+      if (typeUnifyTask.isExecutionCancelled()) {
+        return resultValues;
       }
     }
 
-    if (typeUnifyTask.myIsCancelled()) {
-      throw new UnifyCancelException();
-    }
-
-    return resultValuesFuture;
+    return resultValues;
   }
 
   @Override

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

@@ -11,19 +11,20 @@ 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.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
-public class Variance0Case extends VarianceCase {
+public class UnknownVarianceCase extends VarianceCase {
 
   protected final int variance = 0;
 
-  protected Variance0Case(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
+  protected final AtomicBoolean shouldBreak = new AtomicBoolean(false);
+
+  protected UnknownVarianceCase(boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
     super(isOderConstraint, typeUnifyTask, context);
   }
 
@@ -51,7 +52,6 @@ public class Variance0Case extends VarianceCase {
       a = nextSetAsList.removeFirst();
     }
 
-
     Set<UnifyPair> finalA = a;
     if (!this.isOderConstraint && optOrigPair != null && optOrigPair.isPresent()) {
       if (optOrigPair.get().getBasePair().getLhsType() instanceof PlaceholderType) {
@@ -63,20 +63,20 @@ public class Variance0Case extends VarianceCase {
           nextSetAsList.stream().filter(a_next -> typeUnifyTask.oup.compare(finalA, a_next) != -1).toList()
         );
       }
-      nextSetAsList.remove(a);
     } else if (this.isOderConstraint) {
       nextSetasListRest = typeUnifyTask.oup.maxElements(
         nextSetAsList.stream().filter(a_next -> typeUnifyTask.oup.compare(finalA, a_next) != 1).toList()
       );
     } else {
-      for (int i = 0; i < Math.min(nextSetAsList.size(), 5); i++) {
-        nextSetasListRest.add(nextSetAsList.removeFirst());
-      }
+      nextSetasListRest = (nextSetAsList.size() > 5) ? nextSetAsList.subList(0, 5) : nextSetAsList;
     }
+
+    nextSetAsList.removeAll(nextSetasListRest);
+    // */
   }
 
   @Override
-  public CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> computeParallel(
+  public CompletableFuture<ComputationResults> computeParallel(
     Set<Set<UnifyPair>> elems,
     Set<UnifyPair> eq,
     List<Set<Constraint<UnifyPair>>> oderConstraints,
@@ -88,82 +88,98 @@ public class Variance0Case extends VarianceCase {
     Set<Set<UnifyPair>> result,
     Set<Set<UnifyPair>> aParDef
   ) {
-    CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> resultValues = CompletableFuture.completedFuture(new Tuple<>(
-      new HashSet<>(), 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));
+    Set<UnifyPair> newMethodSignatureConstraintOrig = new HashSet<>(methodSignatureConstraint);
+    if (isOderConstraint) {
+      methodSignatureConstraint.addAll(((Constraint<UnifyPair>) a).getmethodSignatureConstraint());
+    }
+    TypeUnify2Task forkOrig = new TypeUnify2Task(newElemsOrig, newEqOrig, newOderConstraintsOrig, a, fc, context, rekTiefe, newMethodSignatureConstraintOrig);
     typeUnifyTask.addChildTask(forkOrig);
-    // schedule compute() on another thread
     CompletableFuture<Set<Set<UnifyPair>>> forkOrigFuture = CompletableFuture.supplyAsync(forkOrig::compute, context.executor()).thenCompose(f -> f);
-    resultValues = resultValues.thenCombine(forkOrigFuture,
-      (prevResults, currentThreadResult) -> {
+    CompletableFuture<ComputationResults> resultValues = forkOrigFuture.thenApply(
+      (currentThreadResult) -> {
         forkOrig.context.logger().debug("final Orig 0");
         forkOrig.closeLogFile();
-        return new Tuple<>(currentThreadResult, prevResults.getSecond());
+        return new ComputationResults(currentThreadResult);
       });
 
-    //forks.add(forkOrig);
-    if (typeUnifyTask.myIsCancelled()) {
-      throw new UnifyCancelException();
-    }
-    /* FORK ENDE */
-
-    context.logger().debug("a in " + variance + " " + a);
-    context.logger().debug("nextSetasListRest: " + nextSetasListRest.toString());
-
+    int i = 0;
+    Set<Set<UnifyPair>>[] additionalResults = new HashSet[nextSetasListRest.size()];
+    Constraint<UnifyPair>[] extendConstraints = new Constraint[nextSetasListRest.size()];
     while (!nextSetasListRest.isEmpty()) {
-      Set<UnifyPair> nSaL = nextSetasListRest.removeFirst();
-      nextSetAsList.remove(nSaL);
-      context.logger().debug("0 RM" + nSaL.toString());
+      final int finalI = i++;
 
-      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 {
+      Set<UnifyPair> nSaL = nextSetasListRest.removeFirst();
+      context.logger().debug(() -> "0 RM" + nSaL.toString());
+
+      if (this.isOderConstraint) {
         Constraint<UnifyPair> extendConstraint = ((Constraint<UnifyPair>) nSaL).getExtendConstraint();
-        nextSetasListOderConstraints.add(extendConstraint);
+        extendConstraints[finalI] = extendConstraint;
       }
+      else if (!sameEqSet.isEmpty() && !typeUnifyTask.checkNoContradiction(nSaL, sameEqSet, result)) {
+        TypeUnifyTask.noShortendElements++;
+        continue;
+      }
+
       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));
+      Set<UnifyPair> newMethodSignatureConstraint = new HashSet<>(methodSignatureConstraint);
+      if (isOderConstraint) {
+        methodSignatureConstraint.addAll(((Constraint<UnifyPair>) nSaL).getmethodSignatureConstraint());
+      }
+
+      TypeUnify2Task fork = new TypeUnify2Task(newElems, newEq, newOderConstraints, nSaL, fc, context, rekTiefe, newMethodSignatureConstraint);
       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.myIsCancelled()) {
-            throw new UnifyCancelException();
-          }
-          context.logger().debug("fork_res: " + fork_res.toString());
-          context.logger().debug(Boolean.valueOf((typeUnifyTask.isUndefinedPairSetSet(fork_res))).toString());
-          prevResults.getSecond().add(fork_res);
-          if (!typeUnifyTask.isUndefinedPairSetSet(fork_res)) {
-            aParDef.add(fork.getNextSetElement());
-          }
-          fork.context.logger().debug("final 0");
-          fork.closeLogFile();
-          return prevResults;
-        }
-      );
-
-      if (typeUnifyTask.myIsCancelled()) {
-        throw new UnifyCancelException();
-      }
+      resultValues = resultValues.thenCombine(forkFuture, (compResult, forkResult) -> {
+        additionalResults[finalI] = forkResult;
+        context.logger().error("finalI: " + finalI);
+        return compResult;
+      });
     }
 
-    return resultValues;
+
+    int finalI1 = i;
+    return resultValues.thenCompose(compResult -> {
+      var oldResult = compResult.mainResult;
+
+      for (int e = 0; e < finalI1; e++) {
+        Set<Set<UnifyPair>> currentResult = additionalResults[e];
+
+        boolean oldResultInvalid = typeUnifyTask.isUndefinedPairSetSet(oldResult);
+        boolean currentResultInvalid = typeUnifyTask.isUndefinedPairSetSet(currentResult);
+
+        if (!oldResult.isEmpty() && !oldResultInvalid) {
+          boolean shouldBreak = this.eraseInvalidSets(rekTiefe, new HashSet<>(), nextSetAsList);
+          if (shouldBreak) {
+            return CompletableFuture.completedFuture(compResult);
+          }
+        }
+
+        if (this.isOderConstraint) {
+          nextSetasListOderConstraints.add(extendConstraints[e]);
+        }
+
+        if (!currentResultInvalid && oldResultInvalid) {
+          //wenn korrektes Ergebnis gefunden alle Fehlerfaelle loeschen
+          oldResult = currentResult;
+        } else if (oldResultInvalid == currentResultInvalid || oldResult.isEmpty()) {
+          //alle Fehlerfaelle und alle korrekten Ergebnis jeweils adden
+          Set<Set<UnifyPair>> finalOldResult = oldResult;
+          context.logger().debug(() -> "RES var1 ADD:" + finalOldResult.toString() + " " + currentResult.toString());
+          oldResult.addAll(currentResult);
+        }
+      }
+
+      compResult.mainResult = oldResult;
+      return CompletableFuture.completedFuture(compResult);
+    });
   }
 
   @Override
@@ -186,7 +202,6 @@ public class Variance0Case extends VarianceCase {
     if (!this.isOderConstraint) {
       return true;
     } else {
-
       nextSetAsList.removeAll(nextSetasListOderConstraints);
       nextSetasListOderConstraints = new ArrayList<>();
       context.logger().debug("Removed: " + nextSetasListOderConstraints);
@@ -194,19 +209,16 @@ public class Variance0Case extends VarianceCase {
       List<Set<UnifyPair>> notInherited = smallerSetasList.stream()
         .filter(x -> !((Constraint<UnifyPair>) x).isInherited())
         .collect(Collectors.toCollection(ArrayList::new));
-      final List<Set<UnifyPair>> notErased = new ArrayList<>();
+      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);
 
       for (Set<UnifyPair> aPar : aParDef) {
-
-        nextSetAsList.removeAll(nextSetasListOderConstraints);
-        nextSetasListOderConstraints = new ArrayList<>();
-        context.logger().debug("Removed: " + nextSetasListOderConstraints);
         smallerSetasList.clear();
         smallerSetasList.addAll(typeUnifyTask.oup.smallerThan(aPar, nextSetAsList));
         notInherited = smallerSetasList.stream()

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

@@ -5,9 +5,9 @@ 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.Logger;
 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;
@@ -17,11 +17,11 @@ public abstract class VarianceCase {
 
   public static VarianceCase createFromVariance(int variance, boolean isOderConstraint, TypeUnifyTask typeUnifyTask, UnifyContext context) {
     return switch (variance) {
-      case 0 -> new Variance0Case(isOderConstraint, typeUnifyTask, context);
-      case 1 -> new Variance1Case(isOderConstraint, typeUnifyTask, context);
-      case -1 -> new VarianceM1Case(isOderConstraint, typeUnifyTask, context);
-      case 2 -> new Variance2Case(isOderConstraint, typeUnifyTask, context);
-      default -> throw new RuntimeException("Invalid variance: " + 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);
     };
   }
 
@@ -72,7 +72,7 @@ public abstract class VarianceCase {
   /**
    *
    */
-  public abstract CompletableFuture<Tuple<Set<Set<UnifyPair>>, Set<Set<Set<UnifyPair>>>>> computeParallel(
+  public abstract CompletableFuture<ComputationResults> computeParallel(
     Set<Set<UnifyPair>> elems,
     Set<UnifyPair> eq,
     List<Set<Constraint<UnifyPair>>> oderConstraints,
@@ -104,4 +104,29 @@ public abstract class VarianceCase {
     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/model/FiniteClosure.java

@@ -5,6 +5,7 @@ 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;
@@ -126,7 +127,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 		}
 
 		// 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<>());
@@ -238,9 +239,9 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 					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);
 	}
@@ -272,8 +273,8 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 	@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) {
+		Set<UnifyType> ret = greaterHash.get(new hashKeyType(type));
+		if (ret != null) {
 			//context.logger().info(greaterHash);
 			return new HashSet<>(ret);
 		}
@@ -506,35 +507,42 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 	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;
 	}
 	
@@ -566,29 +574,33 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 	
 	@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;
 	}
 	
@@ -603,7 +615,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 	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

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

@@ -170,30 +170,66 @@ 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));
+		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")) {
@@ -201,54 +237,14 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		//}
 		
 		//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 {
@@ -273,59 +269,43 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		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;
 			}
@@ -392,12 +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()) 
+				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;
@@ -418,6 +398,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 				}
 			} else {
 				if (!leftlewc.isEmpty()) {
+					/*
 					Set<UnifyPair> subst;
 					subst = leftlewc.stream().map(x -> { 
 						if (x.getLhsType() instanceof PlaceholderType) {
@@ -426,6 +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/util/Logger.java

@@ -2,11 +2,14 @@ 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;
@@ -16,11 +19,12 @@ 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 static Logger NULL_LOGGER = new NullLogger();
-
   public Logger() {
     this(null, "");
   }
@@ -54,7 +58,7 @@ public class Logger {
   /**
    * 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
+   * @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) {
@@ -69,10 +73,11 @@ public class Logger {
   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 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());
     };
   }
 
@@ -83,7 +88,15 @@ public class Logger {
    */
   protected void print(String s, LogLevel logLevel) {
     String coloredPrefix = this.getPrefix(logLevel);
-    if (logLevel.value > LogLevel.WARNING.value) {
+
+    // 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 {
@@ -92,11 +105,11 @@ public class Logger {
   }
 
   public boolean isLogLevelActive(LogLevel logLevel) {
-    return logLevel.value >= ConsoleInterface.logLevel.value;
+    return logLevel.isHigherOrEqualTo(ConsoleInterface.logLevel);
   }
 
   /**
-   * Write text to the attached writer, if there is any
+   * Write text to the attached writer if there is any
    * @param s   The string to print
    */
   protected void write(String s) {
@@ -113,6 +126,20 @@ public class Logger {
     }
   }
 
+  public String findLogCaller() {
+    StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
+    final String thisFileName = stackTrace[0].getFileName();
+    int i = 0;
+    StackTraceElement currentElement = stackTrace[i];
+    while (++i < stackTrace.length) {
+      currentElement = stackTrace[i];
+      if (!Objects.equals(thisFileName, currentElement.getFileName())) {
+        break;
+      }
+    }
+    return ".(" + currentElement.getFileName() + ":" + currentElement.getLineNumber() + ")";
+  }
+
   /**
    * Base method for logging a string value. Should mostly be used by the Logger internal functions that
    * abstract the logLevel away from the parameters
@@ -123,6 +150,8 @@ public class Logger {
    */
   public void log(String s, LogLevel logLevel) {
     if (isLogLevelActive(logLevel)) {
+      // prepend the call to the logger instance
+      // s = findLogCaller() + "\n" + s;
       this.print(s, logLevel);
       this.write(s);
     }
@@ -140,7 +169,7 @@ public class Logger {
 
 
   /**
-   * Replaces the old FileWriter.write() call
+   * Output a debug message
    * @param s The string to log
    */
   public void debug(String s) {
@@ -154,7 +183,7 @@ public class Logger {
   }
 
   /**
-   * Replaces the old System.out.println() call
+   * Output an info message
    * @param s The string to log
    */
   public void info(String s) {
@@ -195,6 +224,21 @@ public class Logger {
     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
@@ -208,7 +252,7 @@ public class Logger {
         " | " + stackTraceElement.toString()
       ).collect(Collectors.joining("\n"));
 
-    // if there will be a cause printed afterward, announce it with the print of the exception
+    // if there is a cause printed afterward, announce it with the print of the exception
     if (throwable.getCause() != null) {
       s += "\n\nCaused by: ";
     }
@@ -235,22 +279,50 @@ public class Logger {
 
 
   /**
-   * An enum representing the different log levels as integers
+   * 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 {
-    // all the output
+    /** Highly specific output only for debugging */
     DEBUG(0),
-    // a lot of info about the process
+    /** Informational output about the current state of the program */
     INFO(1),
-    // warnings and up
+    /** Warnings about potential issues or an unexpected state **/
     WARNING(2),
-    // only errors and exceptions
-    ERROR(3);
+    /** 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);
+      };
+    }
   }
 
 
@@ -260,7 +332,7 @@ public class Logger {
   private static class NullLogger extends Logger {
     @Override
     public void log(String s, LogLevel logLevel) {
-      // do nothing. Yay
+      // Do nothing. Yay
     }
   }
 }

src/test/java/server/ServerTest.java

@@ -1,9 +1,12 @@
 package server;
 
+import de.dhbwstuttgart.core.ConsoleInterface;
 import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.core.JavaTXServer;
 import de.dhbwstuttgart.environment.CompilationEnvironment;
 import de.dhbwstuttgart.server.SocketClient;
+import de.dhbwstuttgart.server.packet.SetAutoclosePacket;
+import de.dhbwstuttgart.server.packet.UnifyRequestPacket;
 import de.dhbwstuttgart.syntaxtree.ClassOrInterface;
 import de.dhbwstuttgart.syntaxtree.factory.ASTFactory;
 import de.dhbwstuttgart.syntaxtree.factory.UnifyTypeFactory;
@@ -27,6 +30,7 @@ import java.io.Writer;
 import java.nio.file.Path;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
@@ -39,6 +43,10 @@ import static org.junit.Assert.*;
 @Ignore("Server tests create huge overhead, so they are ignored until required")
 public class ServerTest {
 
+  public ServerTest() {
+    ConsoleInterface.unifyServerUrl = Optional.of("ws://localhost:5000");
+  }
+
   @Test
   public void checkServer_Scalar() throws IOException, ClassNotFoundException {
     compareLocalAndServerResult("Scalar.jav");
@@ -52,11 +60,11 @@ public class ServerTest {
   protected void compareLocalAndServerResult(final String filename) throws IOException, ClassNotFoundException {
     File file = Path.of(TestCodegen.path.toString(), filename).toFile();
 
-    // get information from compiler
+    // get information from the compiler
     JavaTXCompiler compiler = new JavaTXCompiler(List.of(file));
 
     // NOW: simulate the call to method typeInference. Once via server and once locally
-    // if everything works, they should neither interfere with each other, nor differ in their result
+    // if everything works, they should neither interfere with each other nor differ in their result
 
     // get the values from the compiler
     PlaceholderRegistry placeholderRegistry = JavaTXCompiler.defaultClientPlaceholderRegistry; //new PlaceholderRegistry();
@@ -86,8 +94,10 @@ public class ServerTest {
     PlaceholderRegistry prCopy = JavaTXCompiler.defaultClientPlaceholderRegistry.deepClone();
     UnifyResultModel urm = new UnifyResultModel(cons, finiteClosure);
     UnifyContext context = new UnifyContext(Logger.NULL_LOGGER, true, urm, usedTasks, prCopy);
-    SocketClient socketClient = new SocketClient("ws://localhost:5000");
-    List<ResultSet> serverResult = socketClient.execute(finiteClosure, cons, unifyCons, context);
+    SocketClient.execute(SetAutoclosePacket.create());
+    List<ResultSet> serverResult = SocketClient.executeAndGet(
+      UnifyRequestPacket.create(finiteClosure, cons, unifyCons, context.placeholderRegistry())
+    ).getResultSet(context);
 
     // close the server
     server.forceStop();

testOut/test.java

@@ -0,0 +1,22 @@
+import java.util.Vector;
+import java.util.List;
+
+class Main {
+
+  public static void main(String[] args) {
+
+
+    var grid = new Vector<Vector<Boolean>>(List.of(
+      new Vector<Boolean>(List.of(false, false, false)),
+      new Vector<Boolean>(List.of(false, false, false)),
+      new Vector<Boolean>(List.of(false, true, false))
+    ));
+
+    BFS img = new BFS();
+    Pos pos = img.search(grid);
+
+    System.out.println("Found at: x=" + pos.x + " | y=" + pos.y);
+  }
+
+
+}