Merge branch 'feat/unify-server' into feat/unify-server-0variance

independentTest.sh

@@ -9,7 +9,7 @@ mkdir $TDIR
 
 cd $TDIR
 git clone $REPO .
-git checkout feat/unify-server
+git checkout feat/unify-server-0variance
 # git checkout dad468368b86bdd5a3d3b2754b17617cee0a9107 # 1:55
 # git checkout a0c11b60e8c9d7addcbe0d3a09c9ce2924e9d5c0 # 2:25
 # git checkout 4cddf73e6d6c9116d3e1705c4b27a8e7f18d80c3 # 2:27
@@ -20,11 +20,10 @@ git checkout feat/unify-server
 
 date "+%Y.%m.%d %H:%M:%S"
 
-# mvn clean compile -DskipTests package
+mkdir testOut
-## prefix each stderr line with " | "
+
-# exec 2> >(trap "" INT TERM; sed 's/^/ | /' >&2)
+#mvn clean compile -DskipTests package
-# echo -e "\nMatrix test:\n |"
+#time java -jar target/JavaTXcompiler-0.1-jar-with-dependencies.jar resources/bytecode/javFiles/Merge.jav -vv -d testOut;
-# time java -jar target/JavaTXcompiler-0.1-jar-with-dependencies.jar resources/bytecode/javFiles/Matrix.jav >/dev/null;
 
 
 mvn clean compile test

pom.xml

@@ -49,11 +49,6 @@ 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>
@@ -158,4 +153,4 @@ http://maven.apache.org/maven-v4_0_0.xsd">
 			<url>file:///${project.basedir}/maven-repository/</url>
 		</repository>
 	</distributionManagement>
-</project>
+</project>

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

@@ -14,7 +14,6 @@ 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.CountDownLatch;
@@ -39,9 +38,13 @@ public class SocketClient extends WebSocketClient {
   private UnifyResultPacket unifyResultPacket;
 
   public SocketClient(String url) {
-    super(URI.create(url), Map.of(
+    super(
-      "packetProtocolVersion", SocketServer.packetProtocolVersion
+      URI.create(url), // target url
-    ));
+      SocketServer.perMessageDeflateDraft, // enable compression
+      Map.of( // headers
+        "packetProtocolVersion", SocketServer.packetProtocolVersion
+      )
+    );
     // make sure, the url is in a valid format
     final String regex = "^wss?://(\\w+(\\.\\w+)?)*:(\\d+)$";
     final Matcher matcher = Pattern.compile(regex).matcher(url);
@@ -51,7 +54,7 @@ public class SocketClient extends WebSocketClient {
   }
 
   public SocketClient(String host, int port, boolean secure) {
-    super(URI.create(String.format("%s://%s:%d/", secure ? "wss" : "ws", host, port)));
+    this(String.format("%s://%s:%d/", secure ? "wss" : "ws", host, port));
   }
 
   /**
@@ -87,8 +90,7 @@ public class SocketClient extends WebSocketClient {
       System.err.println("Server connection interrupted: " + exception);
       this.notifyAll();
       throw new RuntimeException("Aborted server connection", exception);
-    }
+    } catch (Exception exception) {
-    catch (Exception exception) {
       throw new RuntimeException("Exception occurred in server connection: ", exception);
     }
 
@@ -101,15 +103,14 @@ public class SocketClient extends WebSocketClient {
   }
 
   /**
-   *  Specific client-side implementations to handle incoming packets
+   * 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) {
-      catch (Exception exception) {
         this.closeLatch.countDown();
         this.close();
         throw exception;

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

@@ -9,6 +9,7 @@ import de.dhbwstuttgart.server.packet.MessagePacket;
 import de.dhbwstuttgart.server.packet.PacketContainer;
 import de.dhbwstuttgart.util.Logger;
 import java.net.InetSocketAddress;
+import java.util.Collections;
 import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
@@ -17,7 +18,11 @@ import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.java_websocket.WebSocket;
+import org.java_websocket.drafts.Draft;
+import org.java_websocket.drafts.Draft_6455;
+import org.java_websocket.extensions.permessage_deflate.PerMessageDeflateExtension;
 import org.java_websocket.handshake.ClientHandshake;
+import org.java_websocket.server.DefaultWebSocketServerFactory;
 import org.java_websocket.server.WebSocketServer;
 
 public class SocketServer extends WebSocketServer {
@@ -30,8 +35,14 @@ public class SocketServer extends WebSocketServer {
    */
   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());
+
   public SocketServer(int port) {
-    super(new InetSocketAddress(port));
+    super(new InetSocketAddress(port), Collections.singletonList(perMessageDeflateDraft));
+    this.setConnectionLostTimeout(30);
   }
 
   @Override
@@ -201,5 +212,4 @@ public class SocketServer extends WebSocketServer {
       this.id = id;
     }
   }
-
 }

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

@@ -27,7 +27,7 @@ public class ErrorPacket implements IClientToServerPacket, IServerToClientPacket
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketClient socketClient) {
-    System.err.println("[socket] " + "ErrorPacket: " + this.error);
+    SocketClient.logger.error("SocketError: " + this.error);
     if (this.isFatal) {
       throw new RuntimeException("Received fatal error from server: " + this.error);
     }
@@ -35,7 +35,7 @@ public class ErrorPacket implements IClientToServerPacket, IServerToClientPacket
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketServer socketServer) {
-    socketServer.log("ErrorPacket: " + this.error, webSocket);
+    socketServer.log("SocketError: " + this.error, webSocket);
   }
 
 }

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

@@ -24,8 +24,7 @@ public class MessagePacket implements IClientToServerPacket, IServerToClientPack
 
   @JsonIgnore
   public void onHandle(WebSocket webSocket, SocketClient socketClient) {
-    System.err.println("[socket] " + this.message);
+    SocketClient.logger.info("SocketMessage: " + this.message);
-
   }
 
   @JsonIgnore

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

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

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

@@ -22,8 +22,8 @@ import javax.annotation.Nullable;
 
 public class Constraint<A extends IConstraintElement> extends HashSet<A> implements ISerializableData {
   private static final long serialVersionUID = 1L;
-  private Boolean isInherited = false;//wird beides nur für die Method-Constraints benoetigt
+  private boolean isInherited = false;//wird beides nur für die Method-Constraints benoetigt
-  private Boolean isImplemented = false;
+  private boolean isImplemented = false;
 
   /*
    * wird verwendet um bei der Codegenerierung die richtige Methoden - Signatur
@@ -37,27 +37,27 @@ public class Constraint<A extends IConstraintElement> extends HashSet<A> impleme
     super();
   }
 
-  public Constraint(Boolean isInherited, Boolean isImplemented) {
+  public Constraint(boolean isInherited, boolean isImplemented) {
     this.isInherited = isInherited;
     this.isImplemented = isImplemented;
   }
 
-  public Constraint(Boolean isInherited, Boolean isImplemented, Constraint<A> extendConstraint, Set<A> methodSignatureConstraint) {
+  public Constraint(boolean isInherited, boolean isImplemented, Constraint<A> extendConstraint, Set<A> methodSignatureConstraint) {
     this.isInherited = isInherited;
     this.isImplemented = isImplemented;
     this.extendConstraint = extendConstraint;
     this.methodSignatureConstraint = methodSignatureConstraint;
   }
 
-  public void setIsInherited(Boolean isInherited) {
+  public void setIsInherited(boolean isInherited) {
     this.isInherited = isInherited;
   }
 
-  public Boolean isInherited() {
+  public boolean isInherited() {
     return isInherited;
   }
 
-  public Boolean isImplemented() {
+  public boolean isImplemented() {
     return isImplemented;
   }
 

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

@@ -21,7 +21,7 @@ public class Pair implements Serializable, IConstraintElement, ISerializableData
   private SourceLoc location;
 
   private PairOperator eOperator = PairOperator.SMALLER;
-  private Boolean noUnification = false;
+  private boolean noUnification = false;
 
 
   private Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2) {
@@ -43,7 +43,7 @@ public class Pair implements Serializable, IConstraintElement, ISerializableData
     this.location = location;
   }
 
-  public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp, Boolean noUnification) {
+  public Pair(RefTypeOrTPHOrWildcardOrGeneric TA1, RefTypeOrTPHOrWildcardOrGeneric TA2, PairOperator eOp, boolean noUnification) {
     // Konstruktor
     this(TA1, TA2);
     this.eOperator = eOp;
@@ -161,7 +161,7 @@ public class Pair implements Serializable, IConstraintElement, ISerializableData
     String op = data.getValue("op").getOf(String.class);
     SerialMap ta1 = data.getMap("ta1");
     SerialMap ta2 = data.getMap("ta2");
-    Boolean noUnification = data.getValue("noUnification").getOf(Integer.class) == 1;
+    boolean noUnification = data.getValue("noUnification").getOf(Integer.class) == 1;
     SerialMap location = data.getMapOrNull("location");
 
     var pair = new Pair(

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

@@ -858,8 +858,8 @@ public class RuleSet implements IRuleSet{
         								   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 								     } );
 
-		logger.debug("FUNgreater: " + pair);
+		logger.debug(() -> "FUNgreater: " + pair);
-		logger.debug("FUNred: " + result);
+		logger.debug(() -> "FUNred: " + result);
 
 
 		return Optional.of(result);
@@ -927,8 +927,8 @@ public class RuleSet implements IRuleSet{
 
 		Set<UnifyPair> result = new HashSet<UnifyPair>();
 		
-		Integer variance = ((PlaceholderType)rhsType).getVariance();
+		int variance = ((PlaceholderType)rhsType).getVariance();
-		Integer inversVariance = distributeVariance.inverseVariance(variance);
+		int inversVariance = distributeVariance.inverseVariance(variance);
 		
 		UnifyType[] freshPlaceholders = new UnifyType[funNLhsType.getTypeParams().size()];
 		for(int i = 0; i < freshPlaceholders.length-1; i++) {
@@ -946,13 +946,13 @@ public class RuleSet implements IRuleSet{
 		result.add(new UnifyPair(rhsType, funNLhsType.setTypeParams(new TypeParams(freshPlaceholders)), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		
 		result.stream().forEach(x -> { UnifyType l = x.getLhsType();
-									   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); } 
+									   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); }
 									   UnifyType r = x.getRhsType();
 									   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 									 } );
 
-		logger.debug("FUNgreater: " + pair);
+		logger.debug(() -> "FUNgreater: " + pair);
-		logger.debug("FUNgreater: " + result);
+		logger.debug(() -> "FUNgreater: " + result);
 
 		return Optional.of(result);
 	}
@@ -972,8 +972,8 @@ public class RuleSet implements IRuleSet{
 
 		Set<UnifyPair> result = new HashSet<UnifyPair>();
 		
-		Integer variance = ((PlaceholderType)lhsType).getVariance();
+		int variance = ((PlaceholderType)lhsType).getVariance();
-		Integer inversVariance = distributeVariance.inverseVariance(variance);
+		int inversVariance = distributeVariance.inverseVariance(variance);
 		
 		UnifyType[] freshPlaceholders = new UnifyType[funNRhsType.getTypeParams().size()];
 		for(int i = 0; i < freshPlaceholders.length-1; i++) {
@@ -992,14 +992,14 @@ public class RuleSet implements IRuleSet{
 		result.add(new UnifyPair(lhsType, funNRhsType.setTypeParams(new TypeParams(freshPlaceholders)), PairOperator.EQUALSDOT, pair.getSubstitution(), pair.getBasePair()));
 		
 		result.stream().forEach(x -> { UnifyType l = x.getLhsType();
-		   							   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); } 
+		   							   if (l instanceof PlaceholderType) { ((PlaceholderType)l).disableWildcardtable(); }
 		   							   UnifyType r = x.getRhsType();
 		   							   if (r instanceof PlaceholderType) { ((PlaceholderType)r).disableWildcardtable(); }
 									 } );
 
 
-		logger.debug("FUNgreater: " + pair);
+		logger.debug(() -> "FUNgreater: " + pair);
-		logger.debug("FUNsmaller: " + result);
+		logger.debug(() -> "FUNsmaller: " + result);
 
 		return Optional.of(result);
 	}

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

@@ -106,18 +106,18 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
   int rekTiefeField;
 
-  Integer nOfUnify = 0;
+  int nOfUnify = 0;
 
-  Integer noUndefPair = 0;
+  int noUndefPair = 0;
 
-  Integer noAllErasedElements = 0;
+  int noAllErasedElements = 0;
 
   // some statistics for local output (they will not make sense when executed on the server)
   public static int noBacktracking;
   public static int noShortendElements;
   public static int noou = 0;
 
-  Boolean myIsCanceled = false;
+  boolean myIsCanceled = false;
 
   public TypeUnifyTask(UnifyContext context) {
     this.context = context.newWithLogger(Logger.NULL_LOGGER);
@@ -213,7 +213,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 		}		
 }
 */
-  void myCancel(Boolean b) {
+  void myCancel(boolean b) {
     myIsCanceled = true;
   }
 
@@ -292,8 +292,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     rekTiefe++;
     nOfUnify++;
-    context.logger().debug(nOfUnify.toString() + " Unifikation: " + eq.toString());
+    context.logger().debug(() -> nOfUnify + " Unifikation: " + eq.toString());
-    context.logger().debug(nOfUnify.toString() + " Oderconstraints: " + oderConstraints.toString());
+    context.logger().debug(() -> nOfUnify + " Oderconstraints: " + oderConstraints.toString());
 
     /*
      * Variancen auf alle Gleichungen vererben
@@ -323,7 +323,9 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       })
       .peek(UnifyPair::setUndefinedPair)
       .collect(Collectors.toCollection(HashSet::new));
-    context.logger().debug("ocurrPairs: " + ocurrPairs);
+
+    Set<UnifyPair> finalOcurrPairs = ocurrPairs;
+    context.logger().debug(() -> "ocurrPairs: " + finalOcurrPairs);
     if (!ocurrPairs.isEmpty()) {
       Set<Set<UnifyPair>> ret = new HashSet<>();
       ret.add(ocurrPairs);
@@ -352,7 +354,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         })
         .peek(UnifyPair::setUndefinedPair)
         .collect(Collectors.toCollection(HashSet::new));
-      context.logger().debug("ocurrPairs: " + ocurrPairs);
+      Set<UnifyPair> finalOcurrPairs1 = ocurrPairs;
+      context.logger().debug(() -> "ocurrPairs: " + finalOcurrPairs1);
       if (!ocurrPairs.isEmpty()) {
         Set<Set<UnifyPair>> ret = new HashSet<>();
         ret.add(ocurrPairs);
@@ -364,8 +367,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     eq0.forEach(UnifyPair::disableCondWildcards);
 
-    context.logger().debug(nOfUnify.toString() + " Unifikation nach applyTypeUnificationRules: " + eq.toString());
+    context.logger().debug(() ->nOfUnify + " Unifikation nach applyTypeUnificationRules: " + eq.toString());
-    context.logger().debug(nOfUnify.toString() + " Oderconstraints nach applyTypeUnificationRules: " + oderConstraints.toString());
+    context.logger().debug(() -> nOfUnify + " Oderconstraints nach applyTypeUnificationRules: " + oderConstraints.toString());
 
     /*
      * Step 2 and 3: Create a subset eq1s of pairs where both sides are TPH and eq2s of the other pairs
@@ -417,21 +420,21 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     //nicht ausgewertet Faculty Beispiel im 1. Schritt
     //PL 2017-10-03 geloest, muesste noch mit FCs mit kleineren
     //Typen getestet werden.
-    context.logger().debug(nOfUnify.toString() + " Oderconstraints2: " + oderConstraintsOutput.toString());
+    context.logger().debug(() -> nOfUnify + " Oderconstraints2: " + oderConstraintsOutput.toString());
     if (printtag) context.logger().info("secondLevelSets:" + secondLevelSets);
     // If pairs occured that did not match one of the cartesian product cases,
     // those pairs are contradictory and the unification is impossible.
     if (!undefinedPairs.isEmpty()) {
       noUndefPair++;
       for (UnifyPair up : undefinedPairs) {
-        context.logger().debug(noUndefPair.toString() + " UndefinedPairs; " + up);
+        context.logger().debug(() -> noUndefPair + " UndefinedPairs; " + up);
-        context.logger().debug("BasePair; " + up.getBasePair());
+        context.logger().debug(() -> "BasePair; " + up.getBasePair());
       }
       Set<Set<UnifyPair>> error = new HashSet<>();
       undefinedPairs = undefinedPairs.stream().peek(UnifyPair::setUndefinedPair)
         .collect(Collectors.toCollection(HashSet::new));
       error.add(undefinedPairs);
-      undefinedPairs.forEach(x -> context.logger().debug("AllSubst: " + x.getAllSubstitutions().toString()));
+      undefinedPairs.forEach(x -> context.logger().debug(() -> "AllSubst: " + x.getAllSubstitutions().toString()));
       return CompletableFuture.completedFuture(error);
     }
 
@@ -506,14 +509,14 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
      * Step 5: Substitution
      */
     //writeLog("vor Subst: " + eqPrime);
-    context.logger().debug("vor Subst: " + oderConstraints);
+    context.logger().debug(() -> "vor Subst: " + oderConstraints);
     String ocString = oderConstraints.toString();
     List<Set<Constraint<UnifyPair>>> newOderConstraints = new ArrayList<>(oderConstraints);
     Optional<Set<UnifyPair>> eqPrimePrime = rules.subst(eqPrime, newOderConstraints);
     Set<Set<UnifyPair>> unifyres1 = null;
     Set<Set<UnifyPair>> unifyres2 = null;
     if (!ocString.equals(newOderConstraints.toString()))
-      context.logger().debug("nach Subst: " + newOderConstraints);
+      context.logger().debug(() -> "nach Subst: " + newOderConstraints);
 
 
     {// sequentiell (Step 6b is included)
@@ -536,7 +539,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
           return eqPrimePrimeSet;
         });
         if (finalresult && isSolvedForm(eqPrime)) {
-          context.logger().debug("eqPrime:" + eqPrime.toString() + "\n");
+          context.logger().debug(() -> "eqPrime:" + eqPrime.toString() + "\n");
 
           /* methodconstraintsets werden zum Ergebnis hinzugefuegt
            * Anfang
@@ -592,7 +595,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     return eqPrimePrimeSetFuture.thenApply(eqPrimePrimeSet -> {
       eqPrimePrimeSet = eqPrimePrimeSet.stream().filter(x -> isSolvedForm(x) || this.isUndefinedPairSet(x)).collect(Collectors.toCollection(HashSet::new));
       if (!eqPrimePrimeSet.isEmpty() && !isUndefinedPairSetSet(eqPrimePrimeSet)) {
-        context.logger().debug("Result1 " + eqPrimePrimeSet);
+        Set<Set<UnifyPair>> finalEqPrimePrimeSet = eqPrimePrimeSet;
+        context.logger().debug(() -> "Result1 " + finalEqPrimePrimeSet);
       }
       return eqPrimePrimeSet;
     });
@@ -680,14 +684,16 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
      */
     Set<UnifyPair> sameEqSet = new HashSet<>();
     //optOrigPair enthaelt ggf. das Paar a = ty \in  nextSet
-    Optional<UnifyPair> optOrigPair = Optional.empty();
+    Optional<UnifyPair> optOrigPair;
     if (!oderConstraint) {
       optOrigPair = TypeUnifyTaskHelper.findEqualityConstrainedUnifyPair(nextSetElement);
-      context.logger().debug("optOrigPair: " + optOrigPair);
+      context.logger().debug(() -> "optOrigPair: " + optOrigPair);
 
       if (optOrigPair.isPresent()) {
         sameEqSet = TypeUnifyTaskHelper.findConstraintsWithSameTVAssociation(optOrigPair.get(), singleElementSets);
       }
+    } else {
+      optOrigPair = Optional.empty();
     }
 
 
@@ -697,7 +703,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     return resultFuture.thenApply(result -> {
       //2020-02-02: if (variance ==2) Hier Aufruf von filterOverriding einfuegen
-      context.logger().debug("Return computeCR: " + result.toString());
+      context.logger().debug(() ->"Return computeCR: " + result.toString());
       return result;
     });
   }
@@ -724,14 +730,14 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     VarianceCase varianceCase = VarianceCase.createFromVariance(variance, oderConstraint, this, context);
 
-    context.logger().debug("nextSet: " + nextSet.toString());
+    context.logger().debug(() -> "nextSet: " + nextSet.toString());
-    context.logger().debug("nextSetasList: " + prevNextSetAsList.toString());
+    context.logger().debug(() -> "nextSetasList: " + prevNextSetAsList.toString());
 
     varianceCase.selectNextData(this, prevNextSetAsList, optOrigPair);
 
     if (oderConstraint) {//Methodconstraints werden abgespeichert für die Bytecodegenerierung von Methodenaufrufen
       methodSignatureConstraint.addAll(((Constraint<UnifyPair>) varianceCase.a).getmethodSignatureConstraint());
-      context.logger().debug("ERSTELLUNG methodSignatureConstraint: " + methodSignatureConstraint);
+      context.logger().debug(() -> "ERSTELLUNG methodSignatureConstraint: " + methodSignatureConstraint);
       //context.logger().info("ERSTELLUNG methodSignatureConstraint: " +noOfThread+" "+methodSignatureConstraint);
       //context.logger().info("a: " +a);
       //context.logger().info("eq: " +eq);
@@ -740,7 +746,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
     i++;
     Set<Set<UnifyPair>> elems = new HashSet<>(singleElementSets);
-    context.logger().debug("a1: " + rekTiefe + "  " + "variance:  " + variance + " " + varianceCase.a.toString() + "\n");
+    context.logger().debug(() -> "a1: " + rekTiefe + "  " + "variance:  " + variance + " " + varianceCase.a.toString() + "\n");
 
     Set<Set<UnifyPair>> aParDef = new HashSet<>();
 
@@ -814,7 +820,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
             //context.logger().info(a_last);
 
             try {//PL eingefuegt 2019-03-06 da bei map mmer wieder Nullpointer kamen
-              a_last.forEach(x -> context.logger().debug("a_last_elem:" + x + " basepair: " + x.getBasePair()));//PL 2019-05-13 ins try hinzugefuegt Nullpointer-Exception ist in der Zeile aufgetaucht.
+              a_last.forEach(x -> context.logger().debug(() -> "a_last_elem:" + x + " basepair: " + x.getBasePair()));//PL 2019-05-13 ins try hinzugefuegt Nullpointer-Exception ist in der Zeile aufgetaucht.
               List<PlaceholderType> varsLast_a = TypeUnifyTaskHelper.extractMatchingPlaceholderTypes(a_last);
               //[(java.util.Vector<java.lang.Integer> <. gen_aq, , 1), (CEK =. ? extends gen_aq, 1)] KANN VORKOMMEN
               //erstes Element genügt, da vars immer auf die gleichen Elemente zugeordnet werden muessen
@@ -823,11 +829,12 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
               varianceCase.applyComputedResults(result, currentThreadResult, compResult, compRes);
             } catch (NullPointerException e) {
-              context.logger().debug("NullPointerException: " + a_last.toString());
+              context.logger().debug(() -> "NullPointerException: " + a_last.toString());
             }
           } else {
             //alle Fehlerfaelle und alle korrekten Ergebnis jeweils adden
-            context.logger().debug("RES Fst: result: " + result.toString() + " currentThreadResult: " + currentThreadResult.toString());
+            Set<Set<UnifyPair>> finalResult = result;
+            context.logger().debug(() -> "RES Fst: result: " + finalResult.toString() + " currentThreadResult: " + currentThreadResult.toString());
             result.addAll(currentThreadResult);
           }
         }
@@ -841,9 +848,15 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
 
       if (parallel) {
         for (Set<Set<UnifyPair>> par_res : forkResults) {
-          if (variance == 0 && (!result.isEmpty() && (!isUndefinedPairSetSet(currentThreadResult)))) {
+
-            this.cancelChildExecution();
+          if (variance == 0) {
-            return CompletableFuture.completedFuture(result);
+            if (!result.isEmpty() && !isUndefinedPairSetSet(currentThreadResult)) {
+              return CompletableFuture.completedFuture(result);
+            }
+            else {
+              result.addAll(par_res);
+              continue;
+            }
           }
 
           if (!isUndefinedPairSetSet(par_res) && isUndefinedPairSetSet(result)) {
@@ -857,7 +870,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
               || (!isUndefinedPairSetSet(par_res) && !isUndefinedPairSetSet(result))
               || result.isEmpty()) {
               //alle Fehlerfaelle und alle korrekten Ergebnis jeweils adden
-              context.logger().debug("RES var1 ADD:" + result.toString() + " " + par_res.toString());
+              Set<Set<UnifyPair>> finalResult1 = result;
+              context.logger().debug(() ->"RES var1 ADD:" + finalResult1.toString() + " " + par_res.toString());
               result.addAll(par_res);
             }
           }
@@ -882,12 +896,11 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
           return CompletableFuture.completedFuture(result);
         }
 
-        context.logger().debug("a: " + rekTiefe + " variance: " + variance + varianceCase.a.toString());
+        context.logger().debug(() -> "a: " + rekTiefe + " variance: " + variance + varianceCase.a.toString());
       }
       /* auskommentiert um alle Max und min Betrachtung auszuschalten ENDE */
 
       if (isUndefinedPairSetSet(currentThreadResult) && aParDef.isEmpty()) {
-        int nofstred = 0;
         Set<UnifyPair> abhSubst = TypeUnifyTaskHelper.collectFromThreadResult(currentThreadResult, UnifyPair::getAllSubstitutions);
         abhSubst.addAll(
           TypeUnifyTaskHelper.collectFromThreadResult(currentThreadResult, UnifyPair::getThisAndAllBases)
@@ -919,7 +932,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         if (currentThreadResult.size() > 1) {
           // context.logger().info();
         }
-        context.logger().debug("nextSetasList vor filter-Aufruf: " + nextSetAsList);
+        List<Set<UnifyPair>> finalNextSetAsList = nextSetAsList;
+        context.logger().debug(() -> "nextSetasList vor filter-Aufruf: " + finalNextSetAsList);
         if (!oderConstraint) {//PL 2023-02-08 eingefuegt: Bei oderconstraints sind Subststitutionen nicht als Substitutionen in idesem Sinne zu sehen
           nextSetAsList = nextSetAsList.stream().filter(x -> {
               //Boolean ret = false;
@@ -930,23 +944,28 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
             })//.filter(y -> couldBecorrect(reducedUndefResSubstGroundedBasePair, y)) //fuer testzwecke auskommentiert um nofstred zu bestimmen PL 2018-10-10
             .collect(Collectors.toCollection(ArrayList::new));
         }
-        context.logger().debug("nextSetasList nach filter-Aufruf: " + nextSetAsList);
+
-        nofstred = nextSetAsList.size();
+        if (context.logger().isLogLevelActive(Logger.LogLevel.DEBUG)) {
-        //NOCH NICHT korrekt PL 2018-10-12
+          List<Set<UnifyPair>> finalNextSetAsList1 = nextSetAsList;
-        //nextSetasList = nextSetasList.stream().filter(y -> couldBecorrect(reducedUndefResSubstGroundedBasePair, y))
+          context.logger().debug(() -> "nextSetasList nach filter-Aufruf: " + finalNextSetAsList1);
-        //			.collect(Collectors.toCollection(ArrayList::new));
+          int nofstred = nextSetAsList.size();
-        context.logger().debug("currentThreadResult (undef): " + currentThreadResult.toString());
+          //NOCH NICHT korrekt PL 2018-10-12
-        context.logger().debug("abhSubst: " + abhSubst.toString());
+          //nextSetasList = nextSetasList.stream().filter(y -> couldBecorrect(reducedUndefResSubstGroundedBasePair, y))
-        context.logger().debug("a2: " + rekTiefe + " " + varianceCase.a.toString());
+          //			.collect(Collectors.toCollection(ArrayList::new));
-        context.logger().debug("Durchschnitt: " + durchschnitt.toString());
+          context.logger().debug("currentThreadResult (undef): " + currentThreadResult.toString());
-        context.logger().debug("nextSet: " + nextSet.toString());
+          context.logger().debug("abhSubst: " + abhSubst.toString());
-        context.logger().debug("nextSetasList: " + nextSetAsList.toString());
+          context.logger().debug("a2: " + rekTiefe + " " + varianceCase.a.toString());
-        context.logger().debug("Number first erased Elements (undef): " + (len - nofstred));
+          context.logger().debug("Durchschnitt: " + durchschnitt.toString());
-        context.logger().debug("Number second erased Elements (undef): " + (nofstred - nextSetAsList.size()));
+          context.logger().debug("nextSet: " + nextSet.toString());
-        context.logger().debug("Number erased Elements (undef): " + (len - nextSetAsList.size()));
+          context.logger().debug("nextSetasList: " + nextSetAsList.toString());
-        noAllErasedElements += (len - nextSetAsList.size());
+          context.logger().debug("Number first erased Elements (undef): " + (len - nofstred));
-        context.logger().debug("Number of all erased Elements (undef): " + noAllErasedElements.toString());
+          context.logger().debug("Number second erased Elements (undef): " + (nofstred - nextSetAsList.size()));
-        context.logger().debug("Number of Backtracking: " + noBacktracking++);
+          context.logger().debug("Number erased Elements (undef): " + (len - nextSetAsList.size()));
+          noAllErasedElements += (len - nextSetAsList.size());
+          context.logger().debug("Number of all erased Elements (undef): " + noAllErasedElements);
+          context.logger().debug("Number of Backtracking: " + noBacktracking++);
+        }
+
         // context.logger().info("");
       }
       //if (nextSetasList.size() == 0 && isUndefinedPairSetSet(result) && nextSet.size() > 1) {
@@ -956,7 +975,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       //	result.removeIf(y -> isUndefinedPairSet(y));
       //}
       //else result.stream().filter(y -> !isUndefinedPairSet(y));
-      context.logger().debug("currentThreadResult: " + currentThreadResult.toString());
+      context.logger().debug(() -> "currentThreadResult: " + currentThreadResult.toString());
 
       return this.innerCartesianLoop(variance, rekTiefe, oderConstraint, parallel, result, varianceCase.a, nextSet,
         nextSetAsList, optOrigPair, methodSignatureConstraint, singleElementSets, sameEqSet, oderConstraints);
@@ -973,7 +992,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
    *                  the error constraints. Error constraints are added
    * @result contradiction of (a = ty) in sameEqSet
    */
-  public Boolean checkNoContradiction(Set<UnifyPair> a, Set<UnifyPair> sameEqSet, Set<Set<UnifyPair>> result) {
+  public boolean checkNoContradiction(Set<UnifyPair> a, Set<UnifyPair> sameEqSet, Set<Set<UnifyPair>> result) {
 
     //optAPair enthaelt ggf. das Paar a = ty' \in a
     //unterscheidet sich von optOrigPair, da dort a = ty
@@ -993,7 +1012,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       UnifyPair aPair = optAPair.get();
       //writeLog("optOrigPair: " + optOrigPair + " " + "aPair: " + aPair+ " " + "aPair.basePair(): " + aPair.getBasePair());
 
-      context.logger().debug("checkA: " + aPair + "sameEqSet: " + sameEqSet);
+      context.logger().debug(() ->"checkA: " + aPair + "sameEqSet: " + sameEqSet);
       for (UnifyPair sameEq : sameEqSet) {
         if (sameEq.getLhsType() instanceof PlaceholderType) {
           Set<UnifyPair> localEq = new HashSet<>();
@@ -1014,7 +1033,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
             if (result.isEmpty() || isUndefinedPairSetSet(result)) {
               result.addAll(localRes);
             }
-            context.logger().debug("FALSE: " + aPair + "sameEqSet: " + sameEqSet);
+            context.logger().debug(() ->"FALSE: " + aPair + "sameEqSet: " + sameEqSet);
             return false;
           }
         } else {
@@ -1036,12 +1055,12 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
             if (result.isEmpty() || isUndefinedPairSetSet(result)) {
               result.addAll(localRes);
             }
-            context.logger().debug("FALSE: " + aPair + "sameEqSet: " + sameEqSet);
+            context.logger().debug(() ->"FALSE: " + aPair + "sameEqSet: " + sameEqSet);
             return false;
           }
         }
       }
-      context.logger().debug("TRUE: " + aPair + "sameEqSet: " + sameEqSet);
+      context.logger().debug(() ->"TRUE: " + aPair + "sameEqSet: " + sameEqSet);
       return true;
     }
     return true;
@@ -1127,7 +1146,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
             // Through application of the rules, every pair should have one of the above forms.
             // Pairs that do not have one of the aboves form are contradictory.
             else {
-              context.logger().debug("Second erase:" + checkPair);
+              context.logger().debug(() ->"Second erase:" + checkPair);
               return false;
             }
             //*/
@@ -1326,7 +1345,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
    * (as in case 1 where sigma is added to the innermost set).
    */
   protected Set<Set<Set<? extends Set<UnifyPair>>>> calculatePairSets(Set<UnifyPair> eq2s, List<Set<Constraint<UnifyPair>>> oderConstraintsInput, IFiniteClosure fc, Set<UnifyPair> undefined, List<Set<Constraint<UnifyPair>>> oderConstraintsOutput) {
-    context.logger().debug("eq2s: " + eq2s.toString());
+    context.logger().debug(() ->"eq2s: " + eq2s.toString());
     oderConstraintsOutput.addAll(oderConstraintsInput);
     List<Set<Set<? extends Set<UnifyPair>>>> result = new ArrayList<>(9);
 
@@ -1413,10 +1432,12 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       }
     }
 
-    context.logger().debug("eq2s: " + eq2s);
+    if (context.logger().isLogLevelActive(Logger.LogLevel.DEBUG)) {
-    context.logger().debug("eq2sAsListFst: " + eq2sAsListFst);
+      context.logger().debug("eq2s: " + eq2s);
-    context.logger().debug("eq2sAsListSnd: " + eq2sAsListSnd);
+      context.logger().debug("eq2sAsListFst: " + eq2sAsListFst);
-    context.logger().debug("eq2sAsListBack: " + eq2sAsListBack);
+      context.logger().debug("eq2sAsListSnd: " + eq2sAsListSnd);
+      context.logger().debug("eq2sAsListBack: " + eq2sAsListBack);
+    }
 
     eq2sAsList.addAll(eq2sAsListFst);
     eq2sAsList.addAll(eq2sAsListSnd);
@@ -1713,7 +1734,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
     //}
     Set<UnifyType> cs = fc.getAllTypesByName(thetaPrime.getName());//cs= [java.util.Vector<NP>, java.util.Vector<java.util.Vector<java.lang.Integer>>, ????java.util.Vector<gen_hv>???]
 
-    context.logger().debug("cs: " + cs.toString());
+    context.logger().debug(() ->"cs: " + cs.toString());
     //PL 18-02-06 entfernt, kommt durch unify wieder rein
     //cs.add(thetaPrime);
     //PL 18-02-06 entfernt
@@ -1745,7 +1766,8 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
       if ((match.match(ml)).isEmpty()) {
         thetaQs.remove(c);
       }
-      context.logger().debug("thetaQs von " + c + ": " + thetaQs.toString());
+      Set<UnifyType> finalThetaQs = thetaQs;
+      context.logger().debug(() ->"thetaQs von " + c + ": " + finalThetaQs.toString());
       //Set<UnifyType> thetaQs = fc.getChildren(c).stream().collect(Collectors.toCollection(HashSet::new));
       //thetaQs.add(thetaPrime); //PL 18-02-05 wieder geloescht
       //PL 2017-10-03: War auskommentiert habe ich wieder einkommentiert,
@@ -1769,7 +1791,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         for (TypeParams tp : permuteParams(candidateParams))
           thetaQPrimes.add(c.setTypeParams(tp));
       }
-      context.logger().debug("thetaQPrimes von " + c + ": " + thetaQPrimes.toString());
+      context.logger().debug(() ->"thetaQPrimes von " + c + ": " + thetaQPrimes.toString());
       for (UnifyType tqp : thetaQPrimes) {//PL 2020-03-08 umbauen in der Schleife wird nur unifizierbarer Typ gesucht break am Ende
         Collection<PlaceholderType> tphs = tqp.getInvolvedPlaceholderTypes();
         Optional<Unifier> opt = stdUnify.unify(tqp, thetaPrime);
@@ -1842,7 +1864,7 @@ public class TypeUnifyTask extends CancellableTask<CompletableFuture<Set<Set<Uni
         }
       }
     }
-    context.logger().debug("result von " + pair + ": " + result);
+    context.logger().debug(() ->"result von " + pair + ": " + result);
     return result;
   }
 

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

@@ -9,7 +9,7 @@ public record UnifyContext(
   // main logger of a unification
   Logger logger,
   // if the unify algorithm should run in parallel
-  Boolean parallel,
+  boolean parallel,
   // the model for storing calculated results
   UnifyResultModel resultModel,
   // the executor used for thread management in parallel execution
@@ -22,7 +22,7 @@ public record UnifyContext(
 
   public UnifyContext(
     Logger logger,
-    Boolean parallel,
+    boolean parallel,
     UnifyResultModel resultModel,
     UnifyTaskModel usedTasks,
     ExecutorService executor,
@@ -33,7 +33,7 @@ public record UnifyContext(
 
   public UnifyContext(
     Logger logger,
-    Boolean parallel,
+    boolean parallel,
     UnifyResultModel resultModel,
     UnifyTaskModel usedTasks,
     PlaceholderRegistry placeholderRegistry
@@ -52,6 +52,7 @@ public record UnifyContext(
   }
 
   public UnifyContext newWithParallel(boolean parallel) {
+    if (this.parallel == parallel) return this;
     return new UnifyContext(logger, parallel, resultModel, executor, placeholderRegistry, usedTasks);
   }
 

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/Variance2Case.java

@@ -72,8 +72,8 @@ public class Variance2Case extends VarianceCase {
     }
     /* FORK ENDE */
 
-    context.logger().debug("a in " + variance + " " + a);
+    context.logger().debug(() -> "a in " + variance + " " + a);
-    context.logger().debug("nextSetasListRest: " + nextSetasListRest.toString());
+    context.logger().debug(() -> "nextSetasListRest: " + nextSetasListRest.toString());
 
     //Fuer parallele Berechnung der Oder-Contraints wird methodSignature kopiert
     //und jeweils die methodSignature von a bzw. nSaL wieder gelöscht, wenn es keine Lösung ist.

src/main/java/de/dhbwstuttgart/typeinference/unify/cartesianproduct/VarianceM1Case.java

@@ -32,11 +32,11 @@ public class VarianceM1Case extends VarianceCase {
     Optional<UnifyPair> optOrigPair
   ) {
     a = typeUnifyTask.oup.min(nextSetAsList.iterator());
-    context.logger().debug("Min: a in " + variance + " " + a);
+    context.logger().debug(() -> "Min: a in " + variance + " " + a);
     if (this.isOderConstraint) {
       nextSetasListOderConstraints.add(((Constraint<UnifyPair>) a).getExtendConstraint());
     }
-    context.logger().debug("nextSetasListOderConstraints -1: " + nextSetasListOderConstraints);
+    context.logger().debug(() -> "nextSetasListOderConstraints -1: " + nextSetasListOderConstraints);
     nextSetAsList.remove(a);
 
     //Alle minimalen Elemente in nextSetasListRest bestimmen
@@ -88,13 +88,13 @@ public class VarianceM1Case extends VarianceCase {
     }
     /* FORK ENDE */
 
-    context.logger().debug("a in " + variance + " " + a);
+    context.logger().debug(() -> "a in " + variance + " " + a);
-    context.logger().debug("nextSetasListRest: " + nextSetasListRest.toString());
+    context.logger().debug(() -> "nextSetasListRest: " + nextSetasListRest.toString());
 
     while (!nextSetasListRest.isEmpty()) {
       Set<UnifyPair> nSaL = nextSetasListRest.removeFirst();
       nextSetAsList.remove(nSaL);
-      context.logger().debug("-1 RM" + nSaL.toString());
+      context.logger().debug(() -> "-1 RM" + nSaL.toString());
 
       if (!this.isOderConstraint) {
         //ueberpruefung ob zu a =. ty \in nSaL in sameEqSet ein Widerspruch besteht
@@ -118,8 +118,8 @@ public class VarianceM1Case extends VarianceCase {
           if (typeUnifyTask.myIsCancelled()) {
             throw new UnifyCancelException();
           }
-          context.logger().debug("fork_res: " + fork_res.toString());
+          context.logger().debug(() -> "fork_res: " + fork_res.toString());
-          context.logger().debug(Boolean.valueOf((typeUnifyTask.isUndefinedPairSetSet(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());
@@ -148,13 +148,13 @@ public class VarianceM1Case extends VarianceCase {
   ) {
     int resOfCompare = typeUnifyTask.oup.compare(compResult, compRes);
     if (resOfCompare == 1) {
-      context.logger().debug("Geloescht result: " + result);
+      context.logger().debug(() -> "Geloescht result: " + result);
       result.clear();
       result.addAll(currentThreadResult);
     } else if (resOfCompare == 0) {
       result.addAll(currentThreadResult);
     } else if (resOfCompare == -1) {
-      context.logger().debug("Geloescht currentThreadResult: " + currentThreadResult);
+      context.logger().debug(() -> "Geloescht currentThreadResult: " + currentThreadResult);
       //result = result;
     }
   }
@@ -167,13 +167,13 @@ public class VarianceM1Case extends VarianceCase {
   ) {
 
     // context.logger().info("");
-    context.logger().debug("a: " + rekTiefe + " variance: " + variance + a.toString());
+    context.logger().debug(() -> "a: " + rekTiefe + " variance: " + variance + a.toString());
-    context.logger().debug("aParDef: " + aParDef.toString());
+    context.logger().debug(() -> "aParDef: " + aParDef.toString());
     aParDef.add(a);
     Iterator<Set<UnifyPair>> aParDefIt = aParDef.iterator();
     if (this.isOderConstraint) {
       nextSetAsList.removeAll(nextSetasListOderConstraints);
-      context.logger().debug("Removed: " + nextSetasListOderConstraints);
+      context.logger().debug(() -> "Removed: " + nextSetasListOderConstraints);
       nextSetasListOderConstraints = new ArrayList<>();
       while (aParDefIt.hasNext()) {
         Set<UnifyPair> a_new = aParDefIt.next();
@@ -206,9 +206,9 @@ public class VarianceM1Case extends VarianceCase {
         erased.removeAll(notErased);
         nextSetAsList.removeAll(erased);
 
-        context.logger().debug("Removed: " + erased);
+        context.logger().debug(() -> "Removed: " + erased);
 
-        context.logger().debug("Not Removed: " + nextSetAsList);
+        context.logger().debug(() -> "Not Removed: " + nextSetAsList);
 
       }
     } else {
@@ -219,9 +219,9 @@ public class VarianceM1Case extends VarianceCase {
 
         nextSetAsList.removeAll(erased);
 
-        context.logger().debug("Removed: " + erased);
+        context.logger().debug(() -> "Removed: " + erased);
 
-        context.logger().debug("Not Removed: " + nextSetAsList);
+        context.logger().debug(() -> "Not Removed: " + nextSetAsList);
       }
     }
 

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

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

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

@@ -693,7 +693,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 	*/
 	
 	public int compare (UnifyType left, UnifyType right, PairOperator pairop, UnifyContext context) {
-		logger.debug("left: "+ left + " right: " + right + " pairop: " + pairop +"\n");
+		logger.debug(() -> "left: "+ left + " right: " + right + " pairop: " + pairop +"\n");
 		// if (left.getName().equals("Matrix") || right.getName().equals("Matrix"))
 		// 	context.logger().info("");
 		/*
@@ -752,7 +752,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 		Set<UnifyPair> smallerRes = unifyTask.applyTypeUnificationRules(hs, this);
 		
 		//if (left.getName().equals("Vector") || right.getName().equals("AbstractList")) 
-		logger.debug("\nsmallerRes: " + smallerRes);//"smallerHash: " + greaterHash.toString());
+		logger.debug(() -> "\nsmallerRes: " + smallerRes);//"smallerHash: " + greaterHash.toString());
 
 		//Gleichungen der Form a <./=. Theta oder Theta <./=. a oder a <./=. b sind ok.
 		Predicate<UnifyPair> delFun = x -> !((x.getLhsType() instanceof PlaceholderType || 
@@ -761,7 +761,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 													 ((WildcardType)x.getLhsType()).getWildcardedType().equals(x.getRhsType()))
 											 );
 		long smallerLen = smallerRes.stream().filter(delFun).count();
-		logger.debug("\nsmallerLen: " + smallerLen +"\n");
+		logger.debug(() -> "\nsmallerLen: " + smallerLen +"\n");
 		if (smallerLen == 0) return -1;
 		else {
 			up = new UnifyPair(right, left, pairop);
@@ -771,7 +771,7 @@ public class FiniteClosure implements IFiniteClosure, ISerializableData {
 			Set<UnifyPair> greaterRes = unifyTask.applyTypeUnificationRules(hs, this);
 			
 			//if (left.getName().equals("Vector") || right.getName().equals("AbstractList")) 
-			logger.debug("\ngreaterRes: " + greaterRes);//"smallerHash: " + greaterHash.toString());
+			logger.debug(() -> "\ngreaterRes: " + greaterRes);//"smallerHash: " + greaterHash.toString());
 
 			//Gleichungen der Form a <./=. Theta oder Theta <./=. a oder a <./=. b sind ok. 
 			long greaterLen = greaterRes.stream().filter(delFun).count();

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

@@ -81,7 +81,7 @@ public class FunNType extends UnifyType implements ISerializableData {
 	}
 
 	@Override
-	public Boolean wrongWildcard() {
+	public boolean wrongWildcard() {
 		return (new ArrayList<UnifyType>(Arrays.asList(getTypeParams()
 				.get())).stream().filter(x -> (x instanceof WildcardType)).findFirst().isPresent());
 	}

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

@@ -48,7 +48,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 				return fc.compare(left.getRhsType(), right.getRhsType(), PairOperator.SMALLERDOT, context);
 		}}
 		catch (ClassCastException e) {
-			((FiniteClosure)fc).logger.debug("ClassCastException: " + left.toString() + " " + left.getGroundBasePair() + "\n\n");
+			((FiniteClosure)fc).logger.debug(() -> "ClassCastException: " + left.toString() + " " + left.getGroundBasePair() + "\n\n");
 			return -99;
 		}
 	}
@@ -270,7 +270,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		*/
 		
 		
-		Integer compareEq;
+		int compareEq;
 		if (lefteqOder.size() == 1 && righteqOder.size() == 1 && lefteqRet.size() == 1 && righteqRet.size() == 1) {
 			Match m = new Match();
 			if ((compareEq = compareEq(lefteqOder.iterator().next().getGroundBasePair(), righteqOder.iterator().next().getGroundBasePair())) == -1) {
@@ -332,27 +332,27 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 		}
 		
 		
-		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof ExtendsType && leftle.size() == 1  && righteq.size() == 0 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof ExtendsType && leftle.size() == 1  && righteq.isEmpty() && rightle.size() == 1) {
 			return 1;
 		}
 		//Fall 2
-		if (lefteq.size() == 0 && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof ExtendsType && rightle.size() == 1) {
+		if (lefteq.isEmpty() && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof ExtendsType && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 3
-		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof SuperType && leftle.size() == 1  && righteq.size() == 0 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && lefteq.iterator().next().getRhsType() instanceof SuperType && leftle.size() == 1  && righteq.isEmpty() && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 3
-		if (lefteq.size() == 0 && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof SuperType && rightle.size() == 1) {
+		if (lefteq.isEmpty() && leftle.size() == 1 && righteq.size() == 1 && righteq.iterator().next().getRhsType() instanceof SuperType && rightle.size() == 1) {
 			return 1;
 		}
 		//Fall 5
-		if (lefteq.size() == 1 && leftle.size() == 0 && righteq.size() == 1 && rightle.size() == 1) {
+		if (lefteq.size() == 1 && leftle.isEmpty() && righteq.size() == 1 && rightle.size() == 1) {
 			return -1;
 		}
 		//Fall 5
-		if (lefteq.size() == 1 && leftle.size() == 1 && righteq.size() == 1 && rightle.size() == 0) {
+		if (lefteq.size() == 1 && leftle.size() == 1 && righteq.size() == 1 && rightle.isEmpty()) {
 			return 1;
 		}
 		//Fall 5
@@ -360,7 +360,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 			return 0;
 		}
 		// Nur Paare a =. Theta
-		if (leftle.size() == 0 && rightle.size() == 0 && leftlewc.size() == 0 && rightlewc.size() ==0) {
+		if (leftle.isEmpty() && rightle.isEmpty() && leftlewc.isEmpty() && rightlewc.isEmpty()) {
 			Stream<UnifyPair> lseq = lefteq.stream(); //left.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT));
 			Stream<UnifyPair> rseq = righteq.stream(); //right.filter(x -> (x.getLhsType() instanceof PlaceholderType && x.getPairOp() == PairOperator.EQUALSDOT));
 			BinaryOperator<HashMap<UnifyType,UnifyPair>> combiner = (x,y) -> { x.putAll(y); return x;};
@@ -368,11 +368,10 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 			lseq = lseq.filter(x -> !(hm.get(x.getLhsType()) == null));//NOCHMALS UEBERPRUEFEN!!!!
 			lseq = lseq.filter(x -> !x.equals(hm.get(x.getLhsType()))); //Elemente die gleich sind muessen nicht verglichen werden
 			Optional<Integer> si = lseq.map(x -> compareEq(x, hm.get(x.getLhsType()))).reduce((x,y)-> { if (x == y) return x; else return 0; } );
-			if (!si.isPresent()) return 0;
+			return si.orElse(0);
-			else return si.get();
 		}
 		//Fall 1 und 4
-		if (lefteq.size() >= 1 && righteq.size() >= 1 && (leftlewc.size() > 0 || rightlewc.size() > 0)) {
+		if (!lefteq.isEmpty() && !righteq.isEmpty() && (!leftlewc.isEmpty() || !rightlewc.isEmpty())) {
 			//Set<PlaceholderType> varsleft = lefteq.stream().map(x -> (PlaceholderType)x.getLhsType()).collect(Collectors.toCollection(HashSet::new));
 			//Set<PlaceholderType> varsright = righteq.stream().map(x -> (PlaceholderType)x.getLhsType()).collect(Collectors.toCollection(HashSet::new));
 			//filtern des Paares a = Theta, das durch a <. Thata' generiert wurde (nur im Fall 1 relevant)  andere Substitutioen werden rausgefiltert
@@ -395,7 +394,7 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 				Unifier uni = new Unifier();
 				int_Unifier.getValue().get().forEach(x -> uni.add((PlaceholderType) x.getLhsType(), x.getRhsType()));
 				if (!lseq.getRhsType().getName().equals(rseq.getRhsType().getName()) 
-					|| leftlewc.size() == 0 || rightlewc.size() == 0) return int_Unifier.getKey();
+					|| 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));
@@ -415,11 +414,10 @@ public class OrderingUnifyPair extends OrderingExtend<Set<UnifyPair>> {
 						Stream<UnifyPair> lslewcstr = lsleuni.stream().filter(x -> !(hm.get(x.getRhsType()) == null));
 						si = lslewcstr.map(x -> fc.compare(x.getLhsType(), hm.get(x.getRhsType()).getLhsType(), PairOperator.SMALLERDOTWC, context)).reduce((x,y)-> { if (x == y) return x; else return 0; } );
 					}
-					if (!si.isPresent()) return 0;
+					return si.orElse(0);
-					else return si.get();
 				}
 			} else {
-				if (leftlewc.size() > 0) {
+				if (!leftlewc.isEmpty()) {
 					Set<UnifyPair> subst;
 					subst = leftlewc.stream().map(x -> { 
 						if (x.getLhsType() instanceof PlaceholderType) {

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

@@ -134,15 +134,15 @@ public final class PlaceholderType extends UnifyType{
 		wildcardable = true;
 	}
 
-	public void setWildcardtable(Boolean wildcardable) {
+	public void setWildcardtable(boolean wildcardable) {
 		this.wildcardable = wildcardable;
 	}
 
-	public Boolean isInnerType() {
+	public boolean isInnerType() {
 		return innerType;
 	}
 
-	public void setInnerType(Boolean innerType) {
+	public void setInnerType(boolean innerType) {
 		this.innerType = innerType;
 	}
 

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

@@ -32,7 +32,7 @@ public class ReferenceType extends UnifyType implements ISerializableData {
 		return visitor.visit(this, ht);
 	}
 
-	public ReferenceType(String name, Boolean genericTypeVar) {
+	public ReferenceType(String name, boolean genericTypeVar) {
 		super(name, new TypeParams());
 		hashCode = 31 + 17 * typeName.hashCode() + 17 * typeParams.hashCode();
 		this.genericTypeVar = genericTypeVar;

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

@@ -201,7 +201,7 @@ public class UnifyPair implements IConstraintElement, ISerializableData {
 			
 	}
 	
-	public Boolean wrongWildcard() {
+	public boolean wrongWildcard() {
 		return lhs.wrongWildcard() || rhs.wrongWildcard();
 	}
 	

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

@@ -103,7 +103,7 @@ public abstract class UnifyType implements ISerializableData {
     return new ArrayList<>(typeParams.getInvolvedPlaceholderTypes());
 	}
 	
-	public Boolean wrongWildcard() {//default
+	public boolean wrongWildcard() {//default
 		return false;
 	}
 

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

@@ -42,7 +42,7 @@ public abstract class WildcardType extends UnifyType implements ISerializableDat
 	}
 	
 	@Override
-	public Boolean wrongWildcard () {//This is an error
+	public boolean wrongWildcard () {//This is an error
 		return (wildcardedType instanceof WildcardType);
 	}
 	

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

@@ -9,6 +9,7 @@ import java.io.Writer;
 import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.Objects;
+import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
 import static com.diogonunes.jcolor.Ansi.colorize;
@@ -90,6 +91,10 @@ public class Logger {
     }
   }
 
+  public boolean isLogLevelActive(LogLevel logLevel) {
+    return logLevel.value >= ConsoleInterface.logLevel.value;
+  }
+
   /**
    * Write text to the attached writer, if there is any
    * @param s   The string to print
@@ -117,11 +122,22 @@ public class Logger {
    * @param logLevel  The logLevel on which the text should be logged
    */
   public void log(String s, LogLevel logLevel) {
-    if (logLevel.value >= ConsoleInterface.logLevel.value) {
+    if (isLogLevelActive(logLevel)) {
       this.print(s, logLevel);
       this.write(s);
     }
   }
+  public void log(Supplier<String> supp, LogLevel logLevel) {
+    if (isLogLevelActive(logLevel)) {
+      this.log(supp.get(), logLevel);
+    }
+  }
+  public void log(Object obj, LogLevel logLevel) {
+    if (isLogLevelActive(logLevel)) {
+      this.log(obj.toString(), logLevel);
+    }
+  }
+
 
   /**
    * Replaces the old FileWriter.write() call
@@ -131,7 +147,10 @@ public class Logger {
     this.log(s, LogLevel.DEBUG);
   }
   public void debug(Object o) {
-    this.debug(o.toString());
+    this.log(o, LogLevel.DEBUG);
+  }
+  public void debug(Supplier<String> supp) {
+    this.log(supp, LogLevel.DEBUG);
   }
 
   /**
@@ -142,7 +161,10 @@ public class Logger {
     this.log(s, LogLevel.INFO);
   }
   public void info(Object o) {
-    this.info(o.toString());
+    this.log(o, LogLevel.INFO);
+  }
+  public void info(Supplier<String> supp) {
+    this.log(supp, LogLevel.INFO);
   }
 
   /**
@@ -153,7 +175,10 @@ public class Logger {
     this.log(s, LogLevel.WARNING);
   }
   public void warn(Object o) {
-    this.warn(o.toString());
+    this.log(o, LogLevel.WARNING);
+  }
+  public void warn(Supplier<String> supp) {
+    this.log(supp, LogLevel.WARNING);
   }
 
   /**
@@ -164,7 +189,10 @@ public class Logger {
     this.log(s, LogLevel.ERROR);
   }
   public void error(Object o) {
-    this.error(o.toString());
+    this.log(o, LogLevel.ERROR);
+  }
+  public void error(Supplier<String> supp) {
+    this.log(supp, LogLevel.ERROR);
   }
 
   /**