test & fix: add Testcase for Heritage-detection and removed unnecessary creation of Constraints.

src/test/java/AllgemeinTest.java

resources/AllgemeinTest/Bar.java

@@ -0,0 +1,10 @@
+public class Bar{
+
+    void visit(Object o){
+        System.out.println("Object");
+    }
+
+    void visit(Bla f){
+        System.out.println("Foo");
+    }
+}

resources/AllgemeinTest/Box.jav

@@ -1,8 +1,9 @@
-class Box<A> {
+public class Box<A> {
 
 	A a;
 
+	public Box() { }
 	public Box(A a) {
-		this.a = a;
+		//this.a = a;
 	}
 }

resources/AllgemeinTest/Foo.jav

@@ -0,0 +1,6 @@
+public class Foo{
+
+    public accept(Bar b){
+        b.visit(this);
+    }
+}

resources/bytecode/javFiles/Box.java

@@ -1,3 +0,0 @@
-class Box<A> {
-    void m(A a) { }
-}

resources/bytecode/javFiles/Bug332.jav

@@ -0,0 +1,15 @@
+import java.lang.Object;
+
+interface Visitor {
+    public void visit(Object obj);
+    public void visit(ClassA a);
+}
+
+class ClassA {
+    void accept(Visitor v) {
+        v.visit(this);
+    }
+}
+
+public class Bug332 {
+}

resources/bytecode/javFiles/Bug337.jav

@@ -0,0 +1,10 @@
+import java.lang.Integer;
+import java.lang.Number;
+import java.lang.Object;
+
+public class Bug337 {
+    public void main() {
+        Fun1$$<Object, Integer> fun1 = x -> x.hashCode() + 1;
+        Fun1$$<Number, Number> fun2 = fun1;
+    }
+}

resources/bytecode/javFiles/LamRunnable.jav

@@ -1,16 +0,0 @@
-import java.lang.Runnable;
-import java.lang.System;
-import java.lang.String;
-import java.io.PrintStream;
-
-public class LamRunnable {
-
-	public LamRunnable() {
-		Runnable lam = () -> {
-		    System.out.println("lambda");
-		};
-
-		lam.run();
-	}
-}
- 

resources/bytecode/javFiles/SwitchCaseHeritageDetection.jav

@@ -0,0 +1,22 @@
+import java.lang.Integer;
+import java.lang.Object;
+import java.lang.Float;
+import java.lang.String;
+
+public class NumberOrText{}
+public class Text extends NumberOrText{};
+public class Number extends NumberOrText{};
+
+
+public record Cons(Integer a, NumberOrText l){}
+
+
+public class SwitchCaseHeritageDetection {
+    public main(o) {
+         return switch(o) {
+                case Cons(a, Text b) -> "Second Element is a Text";
+                case Cons(a, Number b) -> "Second Element is a Number";
+                default -> "None of the above cases";
+         };
+    }
+}

resources/bytecode/javFiles/SwitchInfered.jav

@@ -10,8 +10,8 @@ public record Rec(Object a,  Object b) {}
 public class SwitchInfered {
     public main(o) {
         return switch (o) {
-        case Rec(a, b) -> a;
-        default -> 0;
+        case Rec(a, b) -> "asd";
+        default -> "cde";
         };
     }
 }

resources/bytecode/javFiles/recordList.jav

@@ -1,15 +0,0 @@
-sealed interface List<A> permits Cons, Nil {}
-
-record Cons(A a, List<A> l) implements List<A> {}
-
-record Nil()implements List<A>  {
-
-    void m(x) {
-        switch(x) {
-        case Cons(a, Cons(b, List<A> l)) -> System.out.println(a);
-        case Cons(a, Nil()) -> System.out.println(a);
-        case Nil() -> System.out.println("Nil");
-        }
-
-    }
-}

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

@@ -5,6 +5,8 @@ import de.dhbwstuttgart.exceptions.NotImplementedException;
 import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.parser.scope.JavaClassName;
 import de.dhbwstuttgart.syntaxtree.ClassOrInterface;
+import de.dhbwstuttgart.syntaxtree.Method;
+import de.dhbwstuttgart.syntaxtree.Pattern;
 import de.dhbwstuttgart.syntaxtree.type.RefType;
 import de.dhbwstuttgart.target.generate.ASTToTargetAST;
 import de.dhbwstuttgart.target.generate.StatementToTargetExpression;
@@ -31,15 +33,21 @@ public class Codegen {
     private final JavaTXCompiler compiler;
     private final ASTToTargetAST converter;
 
+    private class CustomClassWriter extends ClassWriter {
+        public CustomClassWriter() {
+            super(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
+        }
+
+        @Override
+        protected ClassLoader getClassLoader() {
+            return compiler.getClassLoader();
+        }
+    }
+
     public Codegen(TargetStructure clazz, JavaTXCompiler compiler, ASTToTargetAST converter) {
         this.clazz = clazz;
         this.className = clazz.qualifiedName().getClassName();
-        this.cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS) {
-            @Override
-            protected ClassLoader getClassLoader() {
-                return compiler.getClassLoader();
-            }
-        };
+        this.cw = new CustomClassWriter();
         this.compiler = compiler;
         this.converter = converter;
     }
@@ -82,8 +90,6 @@ public class Codegen {
         int localCounter;
         MethodVisitor mv;
         TargetType returnType;
-        // This is used to remember the type from lambda expressions
-        TargetType contextType;
 
         Stack<BreakEnv> breakStack = new Stack<>();
         Stack<Integer> switchResultValue = new Stack<>();
@@ -270,13 +276,43 @@ public class Codegen {
                 mv.visitInsn(I2F);
             else if (dest.equals(TargetType.Double))
                 mv.visitInsn(I2D);
+        } else if (isFunctionalInterface(source) && isFunctionalInterface(dest) &&
+                !(source instanceof TargetFunNType && dest instanceof TargetFunNType)) {
+            boxFunctionalInterface(state, source, dest);
         } else if (!(dest instanceof TargetGenericType)) {
-            boxPrimitive(state, source);
+            //boxPrimitive(state, source);
             mv.visitTypeInsn(CHECKCAST, dest.getInternalName());
             unboxPrimitive(state, dest);
         }
     }
 
+    record TypePair(TargetType from, TargetType to) {}
+    private Map<TypePair, String> funWrapperClasses = new HashMap<>();
+
+    private void boxFunctionalInterface(State state, TargetType source, TargetType dest) {
+        var mv = state.mv;
+        var className = "FunWrapper$$" +
+                source.name().replaceAll("\\.", "\\$") +
+                "$_$" +
+                dest.name().replaceAll("\\.", "\\$");
+
+        funWrapperClasses.put(new TypePair(source, dest), className);
+        mv.visitTypeInsn(NEW, className);
+        mv.visitInsn(DUP_X1);
+        mv.visitInsn(SWAP);
+        mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", "(" + source.toDescriptor() + ")V", false);
+    }
+
+    private boolean isFunctionalInterface(TargetType type) {
+        if (type instanceof TargetFunNType) return true;
+        if (type instanceof TargetRefType) {
+            var clazz = compiler.getClass(new JavaClassName(type.name()));
+            return (clazz.getModifiers() & Modifier.INTERFACE) != 0 && clazz.isFunctionalInterface();
+        }
+
+        return false;
+    }
+
     private TargetType largerType(TargetType left, TargetType right) {
         if (left.equals(TargetType.String) || right.equals(TargetType.String)) {
             return TargetType.String;
@@ -727,41 +763,15 @@ public class Codegen {
         var mv = state.mv;
 
         String methodName = "apply";
-        TargetMethod.Signature signature = null;
-
-        if (!(state.contextType instanceof TargetFunNType ctx)) {
-            var intf = compiler.getClass(new JavaClassName(state.contextType.name()));
-            if (intf != null) {
-                var method = intf.getMethods().stream().filter(m -> Modifier.isAbstract(m.modifier)).findFirst().orElseThrow();
-                methodName = method.getName();
-                var methodParams = new ArrayList<MethodParameter>();
-                for (var i = 0; i < lambda.signature().parameters().size(); i++) {
-                    var param = lambda.signature().parameters().get(i);
-                    var tpe = converter.convert(method.getParameterList().getParameterAt(i).getType());
-                    methodParams.add(param.withType(tpe));
-                }
-                var retType = converter.convert(method.getReturnType());
-                signature = new TargetMethod.Signature(Set.of(), methodParams, retType);
-            }
-        }
-        if (signature == null) {
-            signature = new TargetMethod.Signature(Set.of(), lambda.signature().parameters().stream().map(par -> par.withType(TargetType.Object)).toList(), TargetType.Object);
-        }
-
-        signature = new TargetMethod.Signature(
-            signature.generics(),
-            signature.parameters().stream().map(par ->
-                par.withType(par.pattern().type() instanceof TargetGenericType ? TargetType.Object : par.pattern().type())
-            ).toList(),
-            signature.returnType() instanceof TargetGenericType ? TargetType.Object : signature.returnType()
-        );
+        TargetMethod.Signature signature = new TargetMethod.Signature(Set.of(),
+                lambda.signature().parameters().stream().map(
+                        par -> par.withType(TargetType.Object)).toList(),
+                lambda.signature().returnType() != null ? TargetType.Object : null);
 
         var parameters = new ArrayList<>(lambda.captures());
         parameters.addAll(signature.parameters());
         var implSignature = new TargetMethod.Signature(Set.of(), parameters, lambda.signature().returnType());
 
-        // Normalize
-
         TargetMethod impl;
         if (lambdas.containsKey(lambda)) {
             impl = lambdas.get(lambda);
@@ -782,7 +792,6 @@ public class Codegen {
         params.add(new TargetRefType(clazz.qualifiedName().getClassName()));
         params.addAll(lambda.captures().stream().map(mp -> mp.pattern().type()).toList());
 
-        var descriptor = TargetMethod.getDescriptor(state.contextType, params.toArray(TargetType[]::new));
         mv.visitVarInsn(ALOAD, 0);
         for (var index = 0; index < lambda.captures().size(); index++) {
             var capture = lambda.captures().get(index);
@@ -792,9 +801,42 @@ public class Codegen {
             mv.visitTypeInsn(CHECKCAST, capture.pattern().type().getInternalName());
         }
 
+        var descriptor = TargetMethod.getDescriptor(lambda.type(), params.toArray(TargetType[]::new));
         mv.visitInvokeDynamicInsn(methodName, descriptor, bootstrap, Type.getType(signature.getSignature()), handle, Type.getType(signature.getDescriptor()));
     }
 
+    private int findReturnCode(TargetType returnType) {
+        if (returnType.equals(TargetType.boolean_)
+                || returnType.equals(TargetType.char_)
+                || returnType.equals(TargetType.int_)
+                || returnType.equals(TargetType.short_)
+                || returnType.equals(TargetType.byte_))
+            return IRETURN;
+        else if (returnType.equals(TargetType.long_))
+            return LRETURN;
+        else if (returnType.equals(TargetType.float_))
+            return FRETURN;
+        else if (returnType.equals(TargetType.double_))
+            return DRETURN;
+        return ARETURN;
+    }
+
+    private int findLoadCode(TargetType loadType) {
+        if (loadType.equals(TargetType.boolean_)
+                || loadType.equals(TargetType.char_)
+                || loadType.equals(TargetType.int_)
+                || loadType.equals(TargetType.short_)
+                || loadType.equals(TargetType.byte_))
+            return ILOAD;
+        else if (loadType.equals(TargetType.long_))
+            return LLOAD;
+        else if (loadType.equals(TargetType.float_))
+            return FLOAD;
+        else if (loadType.equals(TargetType.double_))
+            return DLOAD;
+        return ALOAD;
+    }
+
     private void generate(State state, TargetExpression expr) {
         var mv = state.mv;
         switch (expr) {
@@ -819,10 +861,7 @@ public class Codegen {
             break;
         }
         case TargetCast cast:
-            var ctx = state.contextType;
-            state.contextType = cast.type();
             generate(state, cast.expr());
-            state.contextType = ctx;
             convertTo(state, cast.expr().type(), cast.type());
             break;
         case TargetInstanceOf instanceOf:
@@ -867,10 +906,7 @@ public class Codegen {
         case TargetAssign assign: {
             switch (assign.left()) {
                 case TargetLocalVar localVar -> {
-                    var ctype = state.contextType;
-                    state.contextType = localVar.type();
                     generate(state, assign.right());
-                    state.contextType = ctype;
 
                     convertTo(state, assign.right().type(), localVar.type());
                     boxPrimitive(state, localVar.type());
@@ -883,10 +919,7 @@ public class Codegen {
                     if (!(dot.left() instanceof TargetThis && dot.isStatic()))
                         generate(state, dot.left());
 
-                    var ctype = state.contextType;
-                    state.contextType = fieldType;
                     generate(state, assign.right());
-                    state.contextType = ctype;
 
                     convertTo(state, assign.right().type(), fieldType);
                     boxPrimitive(state, fieldType);
@@ -1016,29 +1049,12 @@ public class Codegen {
         case TargetReturn ret: {
             if (ret.expression() != null && state.returnType != null) {
                 if (state.returnType instanceof TargetPrimitiveType) {
-                    var ctype = state.contextType;
-                    state.contextType = state.returnType;
                     generate(state, ret.expression());
-                    state.contextType = ctype;
 
                     unboxPrimitive(state, state.returnType);
-                    if (state.returnType.equals(TargetType.boolean_)
-                        || state.returnType.equals(TargetType.char_)
-                        || state.returnType.equals(TargetType.int_)
-                        || state.returnType.equals(TargetType.short_)
-                        || state.returnType.equals(TargetType.byte_))
-                        mv.visitInsn(IRETURN);
-                    else if (state.returnType.equals(TargetType.long_))
-                        mv.visitInsn(LRETURN);
-                    else if (state.returnType.equals(TargetType.float_))
-                        mv.visitInsn(FRETURN);
-                    else if (state.returnType.equals(TargetType.double_))
-                        mv.visitInsn(DRETURN);
+                    mv.visitInsn(findReturnCode(state.returnType));
                 } else {
-                    var ctype = state.contextType;
-                    state.contextType = state.returnType;
                     generate(state, ret.expression());
-                    state.contextType = ctype;
                     boxPrimitive(state, ret.expression().type());
                     convertTo(state, ret.expression().type(), state.returnType);
                     mv.visitInsn(ARETURN);
@@ -1089,12 +1105,10 @@ public class Codegen {
             for (var i = 0; i < call.args().size(); i++) {
                 var e = call.args().get(i);
                 var arg = call.parameterTypes().get(i);
-                var ctype = state.contextType;
-                state.contextType = arg;
                 generate(state, e);
+                convertTo(state, e.type(), arg);
                 if (!(arg instanceof TargetPrimitiveType))
                     boxPrimitive(state, e.type());
-                state.contextType = ctype;
             }
             var descriptor = call.getDescriptor();
             if (call.owner() instanceof TargetFunNType) // Decay FunN
@@ -1600,6 +1614,85 @@ public class Codegen {
         if (clazz instanceof TargetRecord)
             generateRecordMethods();
 
+        // Generate wrapper classes for function types
+        for (var pair : funWrapperClasses.keySet()) {
+            var className = funWrapperClasses.get(pair);
+            ClassWriter cw2 = new CustomClassWriter();
+            cw2.visit(V1_8, ACC_PUBLIC, className, null, "java/lang/Object", new String[] { pair.to.getInternalName() });
+            cw2.visitField(ACC_PRIVATE, "wrapped", pair.from.toDescriptor(), null, null).visitEnd();
+
+            // Generate constructor
+            var ctor = cw2.visitMethod(ACC_PUBLIC, "<init>", "(" + pair.from.toDescriptor() + ")V", null, null);
+            ctor.visitVarInsn(ALOAD, 0);
+            ctor.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
+            ctor.visitVarInsn(ALOAD, 0);
+            ctor.visitVarInsn(ALOAD, 1);
+            ctor.visitFieldInsn(PUTFIELD, className, "wrapped", pair.from.toDescriptor());
+            ctor.visitInsn(RETURN);
+            ctor.visitMaxs(0, 0);
+            ctor.visitEnd();
+
+            String methodName = "apply";
+            String fromDescriptor = null;
+            TargetType fromReturn = null;
+            if (!(pair.from instanceof TargetFunNType funNType)) {
+                var fromClass = compiler.getClass(new JavaClassName(pair.from.name()));
+                var fromMethod = fromClass.getMethods().stream().filter(m -> (m.modifier & ACC_ABSTRACT) != 0).findFirst().orElseThrow();
+                methodName = fromMethod.name;
+
+                fromReturn = converter.convert(fromMethod.getReturnType());
+                var fromParams = converter.convert(fromMethod.getParameterList(), converter.generics.javaGenerics()).stream().map(m -> m.pattern().type()).toArray(TargetType[]::new);
+                fromDescriptor = TargetMethod.getDescriptor(fromReturn, fromParams);
+            } else {
+                fromReturn = funNType.returnArguments() > 0 ? TargetType.Object : null;
+                fromDescriptor = funNType.toMethodDescriptor();
+            }
+
+            var toClass = compiler.getClass(new JavaClassName(pair.to.name()));
+            var toMethod = toClass.getMethods().stream().filter(m -> (m.modifier & ACC_ABSTRACT) != 0).findFirst().orElseThrow();
+            var toReturn = converter.convert(toMethod.getReturnType());
+            var toParams = converter.convert(toMethod.getParameterList(), converter.generics.javaGenerics()).stream().map(m -> m.pattern().type()).toArray(TargetType[]::new);
+            var toDescriptor = TargetMethod.getDescriptor(toReturn, toParams);
+
+            // Generate wrapper method
+            var mv = cw2.visitMethod(ACC_PUBLIC, toMethod.name, toDescriptor, null, null);
+            var state = new State(null, mv, 0);
+
+            mv.visitVarInsn(ALOAD, 0);
+            mv.visitFieldInsn(GETFIELD, className, "wrapped", pair.from.toDescriptor());
+            for (var i = 0; i < toParams.length; i++) {
+                var arg = toParams[i];
+                mv.visitVarInsn(findLoadCode(arg), i + 1);
+            }
+            mv.visitMethodInsn(INVOKEINTERFACE, pair.from.getInternalName(), methodName, fromDescriptor, true);
+            if (fromReturn != null) {
+                if (toReturn instanceof TargetPrimitiveType) {
+                    convertTo(state, fromReturn, TargetType.toWrapper(toReturn));
+                } else convertTo(state, fromReturn, toReturn);
+            }
+
+            if (toReturn != null)
+                mv.visitInsn(findReturnCode(toReturn));
+
+            else mv.visitInsn(RETURN);
+            mv.visitMaxs(0, 0);
+            mv.visitEnd();
+
+            cw2.visitEnd();
+            var bytes = cw2.toByteArray();
+            converter.auxiliaries.put(className, bytes);
+
+            // TODO These class loading shenanigans happen in a few places, the tests load the classes individually.
+            // Instead we should just look at the folder.
+            try {
+                converter.classLoader.findClass(className);
+            } catch (ClassNotFoundException e) {
+                try {
+                    converter.classLoader.loadClass(bytes);
+                } catch (LinkageError ignored) {}
+            }
+        }
+
         cw.visitEnd();
         return cw.toByteArray();
     }

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

@@ -1,11 +1,13 @@
 package de.dhbwstuttgart.bytecode;
 
+import de.dhbwstuttgart.syntaxtree.statement.Break;
 import de.dhbwstuttgart.target.tree.TargetGeneric;
 import de.dhbwstuttgart.target.tree.type.*;
 import org.objectweb.asm.ClassWriter;
 import org.objectweb.asm.MethodVisitor;
 import org.objectweb.asm.Type;
 
+import java.sql.Array;
 import java.util.*;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -33,6 +35,36 @@ public class FunNGenerator {
     public static class GenericParameters {
         int start;
         public List<TargetType> parameters = new ArrayList<>();
+        final String descriptor;
+        public final List<TargetType> inParams;
+        public final List<TargetType> realParams;
+
+        public GenericParameters(List<TargetType> params, int numReturns) {
+            this.realParams = params;
+            this.inParams = flattenTypeParams(params);
+            var type = new TargetRefType(FunNGenerator.getSuperClassName(params.size() - 1, numReturns), params);
+            descriptor = applyDescriptor(type, this);
+        }
+
+        private static List<TargetType> flattenTypeParams(List<TargetType> params) {
+            var res = new ArrayList<TargetType>();
+            for (var param : params) {
+                if (param instanceof TargetSpecializedType tspec) {
+                    res.addAll(flattenTypeParams(tspec.params()));
+                } else {
+                    res.add(param);
+                }
+            }
+            return res;
+        }
+
+        public TargetType getReturnType() {
+            return FunNGenerator.getReturnType(realParams);
+        }
+
+        public List<TargetType> getArguments() {
+            return FunNGenerator.getArguments(realParams);
+        }
     }
 
     private static String applyDescriptor(TargetType type, GenericParameters gep) {
@@ -69,7 +101,7 @@ public class FunNGenerator {
         return applyNameDescriptor(type).replace("/", "$").replace(";", "$_$");
     }
 
-    public static byte[] generateSuperBytecode(int numberArguments) {
+    public static byte[] generateSuperBytecode(int numberArguments, int numReturnTypes) {
         StringBuilder superFunNClassSignature = new StringBuilder("<");
         StringBuilder superFunNMethodSignature = new StringBuilder("(");
         StringBuilder superFunNMethodDescriptor = new StringBuilder("(");
@@ -80,30 +112,34 @@ public class FunNGenerator {
             superFunNMethodDescriptor.append(objectSignature);
         }
         superFunNClassSignature.append(String.format("%s:%s>%s", returnGeneric, objectSignature, objectSignature));
-        superFunNMethodSignature.append(String.format(")T%s;", returnGeneric));
-        superFunNMethodDescriptor.append(String.format(")%s", objectSignature));
+        if (numReturnTypes > 0) {
+            superFunNMethodSignature.append(String.format(")T%s;", returnGeneric));
+            superFunNMethodDescriptor.append(String.format(")%s", objectSignature));
+        } else {
+            superFunNMethodSignature.append(")V");
+            superFunNMethodDescriptor.append(")V");
+        }
 
         System.out.println(superFunNMethodSignature);
 
         ClassWriter classWriter = new ClassWriter(0);
         MethodVisitor methodVisitor;
-        classWriter.visit(bytecodeVersion, ACC_PUBLIC | ACC_ABSTRACT | ACC_INTERFACE, getSuperClassName(numberArguments), superFunNClassSignature.toString(), objectSuperType, null);
+        classWriter.visit(bytecodeVersion, ACC_PUBLIC | ACC_ABSTRACT | ACC_INTERFACE, getSuperClassName(numberArguments, numReturnTypes), superFunNClassSignature.toString(), objectSuperType, null);
         methodVisitor = classWriter.visitMethod(ACC_PUBLIC | ACC_ABSTRACT, methodName, superFunNMethodDescriptor.toString(), superFunNMethodSignature.toString(), null);
         methodVisitor.visitEnd();
         classWriter.visitEnd();
         return classWriter.toByteArray();
     }
 
-    public static String getSuperClassName(int numberArguments) {
-        return String.format("Fun%d$$", numberArguments);
+    public static String getSuperClassName(int numberArguments, int returnArguments) {
+        return returnArguments > 0 ? String.format("Fun%d$$", numberArguments) : String.format("FunVoid%d$$", numberArguments);
     }
 
-    public static byte[] generateSpecializedBytecode(List<TargetType> argumentTypes, TargetType returnType, GenericParameters gep) {
-        List<TargetType> parameters = Stream
-                .concat(argumentTypes.stream(), Stream.of(returnType))
-                .toList();
+    public static byte[] generateSpecializedBytecode(GenericParameters gep, List<String> superInterfaces) {
+        var argumentTypes = gep.getArguments();
+        var returnType = gep.getReturnType();
 
-        StringBuilder funNClassSignature = new StringBuilder(objectSignature + applyDescriptor(new TargetRefType(getSuperClassName(argumentTypes.size()), parameters), gep));
+        StringBuilder funNClassSignature = new StringBuilder(objectSignature + gep.descriptor);
         boolean containsGeneric = false;
 
         String genericSignature = "<";
@@ -114,10 +150,18 @@ public class FunNGenerator {
 
         genericSignature += ">";
         if (containsGeneric) funNClassSignature.insert(0, genericSignature);
-        System.out.println(funNClassSignature.toString());
+
+        for (var superInterface : superInterfaces) {
+            funNClassSignature.append('L');
+            funNClassSignature.append(superInterface);
+            funNClassSignature.append(';');
+        }
+
+        var interfaces = new ArrayList<>(superInterfaces);
+        interfaces.add(getSuperClassName(argumentTypes.size(), returnType != null ? 1 : 0));
 
         ClassWriter classWriter = new ClassWriter(0);
-        classWriter.visit(bytecodeVersion, ACC_PUBLIC | ACC_ABSTRACT | ACC_INTERFACE, getSpecializedClassName(argumentTypes, returnType), funNClassSignature.toString(), objectSuperType, new String[]{getSuperClassName(argumentTypes.size())});
+        classWriter.visit(bytecodeVersion, ACC_PUBLIC | ACC_ABSTRACT | ACC_INTERFACE, getSpecializedClassName(argumentTypes, returnType), funNClassSignature.toString(), objectSuperType, interfaces.toArray(String[]::new));
         classWriter.visitEnd();
         return classWriter.toByteArray();
     }
@@ -133,14 +177,24 @@ public class FunNGenerator {
         }
     }
 
+    public static String getSpecializedClassName(GenericParameters gep) {
+        return getSpecializedClassName(gep.getArguments(), gep.getReturnType());
+    }
+
     public static String getSpecializedClassName(List<TargetType> argumentTypes, TargetType returnType) {
-        return String.format("Fun%d$$%s%s",
+        var arguments = argumentTypes
+            .stream()
+            .map(FunNGenerator::encodeType)
+            .collect(Collectors.joining());
+
+        if (returnType != null)
+            return String.format("Fun%d$$%s%s",
+                argumentTypes.size(),
+                arguments,
+                encodeType(returnType));
+        else return String.format("FunVoidImpl%d$$%s",
             argumentTypes.size(),
-            argumentTypes
-                    .stream()
-                    .map(FunNGenerator::encodeType)
-                    .collect(Collectors.joining()),
-            encodeType(returnType));
+            arguments);
     }
 
     public static List<TargetType> getArguments(List<TargetType> list) {
@@ -151,8 +205,8 @@ public class FunNGenerator {
     }
 
     public static TargetType getReturnType(List<TargetType> list) {
-        if(list.size() == 0)
+        if(list.isEmpty())
             throw new IndexOutOfBoundsException();
-        return list.get(list.size() - 1);
+        return list.getLast();
     }
 }

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

@@ -66,7 +66,7 @@ public class JavaTXCompiler {
 	Boolean resultmodel = true;
     public final Map<File, SourceFile> sourceFiles = new HashMap<>();
 
-    Boolean log = true; //gibt an ob ein Log-File nach System.getProperty("user.dir")+""/logFiles/"" geschrieben werden soll?
+    Boolean log = false; //gibt an ob ein Log-File nach System.getProperty("user.dir")+""/logFiles/"" geschrieben werden soll?
     public volatile UnifyTaskModel usedTasks = new UnifyTaskModel();
     public final DirectoryClassLoader classLoader;
 
@@ -783,6 +783,7 @@ public class JavaTXCompiler {
 			});
 		}
 		generatedGenerics.put(sf, converter.javaGenerics());
+		converter.generateFunNTypes();
 		return generatedClasses;
 	}
 

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

@@ -158,7 +158,8 @@ public class FCGenerator {
     }
 
     /**
-     * Tauscht die GTVs in einem Typ gegen die entsprechenden Typen in der übergebenen Map aus.
+     * Tauscht die GTVs in einem Typ gegen die entsprechenden Typen in der übergebenen Map aus auf der direkten Argumentebene.
+     * Hier sind keine Wildcards zulässig
      */
     private static class TypeExchanger implements TypeVisitor<RefTypeOrTPHOrWildcardOrGeneric>{
 
@@ -172,7 +173,7 @@ public class FCGenerator {
         public RefTypeOrTPHOrWildcardOrGeneric visit(RefType refType) {
             List<RefTypeOrTPHOrWildcardOrGeneric> params = new ArrayList<>();
             for(RefTypeOrTPHOrWildcardOrGeneric param : refType.getParaList()){
-                params.add(param.acceptTV(this));
+                params.add(param.acceptTV(new TypeExchangerInner(gtvs)));
             }
             RefTypeOrTPHOrWildcardOrGeneric ret = new RefType(refType.getName(), params, new NullToken());
             return ret;
@@ -201,4 +202,51 @@ public class FCGenerator {
         }
 
     }
+    
+    /**
+     * Tauscht die GTVs in einem Typ gegen die entsprechenden Typen in der übergebenen Map aus auf den Argumenten der Argumente.
+     * Hier sind Wildcards zulässig
+     */
+    private static class TypeExchangerInner implements TypeVisitor<RefTypeOrTPHOrWildcardOrGeneric>{
+
+        private final HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> gtvs;
+
+        TypeExchangerInner(HashMap<String, RefTypeOrTPHOrWildcardOrGeneric> gtvs){
+            this.gtvs = gtvs;
+        }
+
+        @Override
+        public RefTypeOrTPHOrWildcardOrGeneric visit(RefType refType) {
+            List<RefTypeOrTPHOrWildcardOrGeneric> params = new ArrayList<>();
+            for(RefTypeOrTPHOrWildcardOrGeneric param : refType.getParaList()){
+                params.add(param.acceptTV(this));
+            }
+            RefTypeOrTPHOrWildcardOrGeneric ret = new RefType(refType.getName(), params, new NullToken());
+            return ret;
+        }
+
+        @Override
+        public RefTypeOrTPHOrWildcardOrGeneric visit(SuperWildcardType superWildcardType) {
+            return superWildcardType;
+        }
+
+        @Override
+        public RefTypeOrTPHOrWildcardOrGeneric visit(TypePlaceholder typePlaceholder) {
+            throw new DebugException("Dieser Fall darf nicht auftreten");
+        }
+
+        @Override
+        public RefTypeOrTPHOrWildcardOrGeneric visit(ExtendsWildcardType extendsWildcardType) {
+            return extendsWildcardType;
+        }
+
+        @Override
+        public RefTypeOrTPHOrWildcardOrGeneric visit(GenericRefType genericRefType) {
+            if(! gtvs.containsKey(genericRefType.getParsedName()))
+                throw new DebugException("Dieser Fall darf nicht auftreten");
+            return gtvs.get(genericRefType.getParsedName());
+        }
+
+    }
+    
 }

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

@@ -188,9 +188,8 @@ public class ClassOrInterface extends SyntaxTreeNode implements TypeScope {
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;
-    if (o == null || getClass() != o.getClass()) return false;
-    ClassOrInterface that = (ClassOrInterface) o;
-    return Objects.equals(name, that.name);
+    if (!(o instanceof ClassOrInterface other)) return false;
+    return Objects.equals(name, other.name);
   }
 
   @Override

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

@@ -34,6 +34,7 @@ public class ASTFactory {
 	private static final HashMap<java.lang.Class, ClassOrInterface> cache = new HashMap<>();
 
 	public static ClassOrInterface createClass(java.lang.Class jreClass) {
+		System.out.println(jreClass);
 		if (cache.containsKey(jreClass))
 			return cache.get(jreClass);
 
@@ -173,6 +174,7 @@ public class ASTFactory {
 			superClass = (RefType) createType(java.lang.Object.class);
 		}
 		List<RefType> implementedInterfaces = new ArrayList<>();
+		System.out.println(jreClass);
 		for (Type jreInterface : jreClass.getGenericInterfaces()) {
 			implementedInterfaces.add((RefType) createType(jreInterface));
 		}

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

@@ -5,7 +5,6 @@ import de.dhbwstuttgart.bytecode.FunNGenerator;
 import de.dhbwstuttgart.core.JavaTXCompiler;
 import de.dhbwstuttgart.environment.ByteArrayClassLoader;
 import de.dhbwstuttgart.environment.IByteArrayClassLoader;
-import de.dhbwstuttgart.exceptions.NotImplementedException;
 import de.dhbwstuttgart.parser.NullToken;
 import de.dhbwstuttgart.parser.scope.JavaClassName;
 import de.dhbwstuttgart.syntaxtree.*;
@@ -18,23 +17,25 @@ import de.dhbwstuttgart.target.tree.expression.*;
 import de.dhbwstuttgart.target.tree.type.*;
 import de.dhbwstuttgart.typeinference.result.*;
 
-import javax.sql.rowset.RowSetWarning;
-import java.lang.annotation.Target;
 import java.util.*;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import java.util.stream.StreamSupport;
 
 /**
  * @author dholle
  */
 public class ASTToTargetAST {
 
+    record SignaturePair(TypePlaceholder signature, RefTypeOrTPHOrWildcardOrGeneric parameter) {};
+    record SignaturePairTarget(TargetType signature, TargetType parameter) {}
+
     public static RefType OBJECT = ASTFactory.createObjectType(); // TODO It would be better if I could call this directly but the hashcode seems to change
 
     protected List<Generics> all;
     public Generics generics;
     final Map<ClassOrInterface, Set<GenericTypeVar>> userDefinedGenerics = new HashMap<>();
+    final Map<Method, Set<SignaturePair>> tphsInMethods = new HashMap<>();
+    private Method currentMethod;
 
     public final JavaTXCompiler compiler;
 
@@ -56,7 +57,7 @@ public class ASTToTargetAST {
     }
 
 
-    protected IByteArrayClassLoader classLoader;
+    public IByteArrayClassLoader classLoader;
     protected SourceFile sourceFile;
 
     public ASTToTargetAST(List<ResultSet> resultSets) {
@@ -78,6 +79,12 @@ public class ASTToTargetAST {
         this.generics = all.get(0);
     }
 
+    public void addSignaturePair(TypePlaceholder signature, RefTypeOrTPHOrWildcardOrGeneric parameter) {
+        var set = tphsInMethods.getOrDefault(currentMethod, new HashSet<>());
+        set.add(new SignaturePair(signature, parameter));
+        tphsInMethods.put(currentMethod, set);
+    }
+
     Optional<Method> findMethod(ClassOrInterface owner, String name, List<TargetType> argumentList) {
         Optional<Method> method = Optional.empty();
         while (method.isEmpty()) {
@@ -131,6 +138,40 @@ public class ASTToTargetAST {
         return ret;
     }
 
+    public List<List<TargetMethod>> groupOverloads(ClassOrInterface input, List<Method> methods) {
+        var res = new ArrayList<List<TargetMethod>>();
+        for (var method : methods) {
+            // Convert all methods
+            var methodsWithTphs = convert(input, method);
+            // Then check for methods with the same signature
+            var mapOfSignatures = new HashMap<TargetMethod.Signature, List<MethodWithTphs>>();
+            for (var m : methodsWithTphs) {
+                var methodsWithSameSignature = mapOfSignatures.getOrDefault(m.method.signature(), new ArrayList<>());
+                methodsWithSameSignature.add(m);
+                mapOfSignatures.put(m.method.signature(), methodsWithSameSignature);
+            }
+
+            var resMethods = new HashSet<TargetMethod>();
+            for (var methodsWithSignature : mapOfSignatures.values()) {
+                outer: for (var m1 : methodsWithSignature) {
+                    for (var m2 : methodsWithSignature) {
+                        for (var i = 0; i < m1.args.size(); i++) {
+                            var arg1 = m1.args.get(i);
+                            var arg2 = m2.args.get(i);
+                            if (arg1.parameter.equals(arg2.parameter)) {
+                                if (isSupertype(arg1.signature, arg2.signature) &&
+                                    !arg1.signature.equals(arg2.signature)) continue outer;
+                            }
+                        }
+                    }
+                    resMethods.add(m1.method);
+                }
+            }
+            res.add(resMethods.stream().toList());
+        }
+        return res;
+    }
+
     public TargetStructure convert(ClassOrInterface input) {
         Set<TargetGeneric> javaGenerics = new HashSet<>();
         Set<TargetGeneric> txGenerics = new HashSet<>();
@@ -161,11 +202,11 @@ public class ASTToTargetAST {
         var superInterfaces = input.getSuperInterfaces().stream().map(clazz -> convert(clazz, generics.javaGenerics)).toList();
         var constructors = input.getConstructors().stream().map(constructor -> this.convert(input, constructor, finalFieldInitializer)).flatMap(List::stream).toList();
         var fields = input.getFieldDecl().stream().map(this::convert).toList();
-        var methods = groupOverloads(input.getMethods()).stream().map(m -> convert(input, m)).flatMap(Set::stream).toList();
+        var methods = groupOverloads(input, input.getMethods()).stream().flatMap(List::stream).toList();
 
         TargetMethod staticConstructor = null;
         if (input.getStaticInitializer().isPresent())
-            staticConstructor = this.convert(input, input.getStaticInitializer().get()).stream().findFirst().orElseThrow();
+            staticConstructor = this.convert(input, input.getStaticInitializer().get()).stream().findFirst().orElseThrow().method;
 
         if (input instanceof Record)
             return new TargetRecord(input.getModifiers(), input.getClassName(), javaGenerics, txGenerics, superInterfaces, constructors, staticConstructor, fields, methods);
@@ -206,6 +247,7 @@ public class ASTToTargetAST {
         generics = all.get(0);
         List<TargetConstructor> result = new ArrayList<>();
         Set<List<MethodParameter>> parameterSet = new HashSet<>();
+        this.currentMethod = input;
 
         for (var s : all) {
             generics = s;
@@ -225,56 +267,6 @@ public class ASTToTargetAST {
         return result;
     }
 
-    /**
-     * This only considers type patterns, all other methods aren't grouped together
-     * @param a
-     * @param b
-     * @return
-     */
-    private boolean signatureEquals(Method a, Method b) {
-        if (!a.name.equals(b.name)) return false;
-        var para = a.getParameterList().getFormalparalist();
-        var parb = b.getParameterList().getFormalparalist();
-        if (para.size() != parb.size()) return false;
-
-        for (var i = 0; i < para.size(); i++) {
-            var pa = para.get(i);
-            var pb = parb.get(i);
-
-            if (pa instanceof RecordPattern rpa) {
-                if (pb instanceof RecordPattern rpb) {
-                    if (rpa.getType().equals(rpb.getType())) continue;
-                }
-                return false;
-            } else if (pa.getType().equals(pb.getType())) {
-                continue;
-            }
-            return false;
-        }
-
-        return true;
-    }
-
-    // TODO Nested patterns
-    private List<List<Method>> groupOverloads(List<Method> input) {
-        var done = new HashSet<Method>();
-        var res = new ArrayList<List<Method>>();
-        for (var method : input) {
-            if (done.contains(method)) continue;
-            var overloads = new ArrayList<Method>();
-            overloads.add(method);
-            done.add(method);
-            for (var method2 : input) {
-                if (!done.contains(method2) && signatureEquals(method, method2)) {
-                    done.add(method2);
-                    overloads.add(method2);
-                }
-            }
-            res.add(overloads);
-        }
-        return res;
-    }
-
     private String encodeName(String name, ParameterList params) {
         var res = new StringBuilder();
         res.append(name);
@@ -290,9 +282,9 @@ public class ASTToTargetAST {
         return res.toString();
     }
 
-    private Set<TargetMethod> convert(ClassOrInterface clazz, List<Method> overloadedMethods) {
+    private List<TargetMethod> convert(ClassOrInterface clazz, List<Method> overloadedMethods) {
         if (overloadedMethods.size() == 1) {
-            return convert(clazz, overloadedMethods.getFirst());
+            return convert(clazz, overloadedMethods.getFirst()).stream().map(m -> m.method()).toList();
         }
         var methods = new ArrayList<Method>();
         for (var method : overloadedMethods) {
@@ -329,10 +321,11 @@ public class ASTToTargetAST {
         var entryPoint = new Method(template.modifier, template.name, template.getReturnType(), params, block, template.getGenerics(), new NullToken());
 
         res.add(entryPoint); // TODO*/
-        var res = new HashSet<TargetMethod>();
+        var res = new ArrayList<TargetMethod>();
         for (var method : methods) {
             var overloads = convert(clazz, method);
-            for (var overload : overloads) {
+            for (var m : overloads) {
+                var overload = m.method;
                 if (res.contains(overload)) throw new CodeGenException("Duplicate method found: " + overload.name() + " with signature " + overload.signature().getSignature());
                 res.add(overload);
             }
@@ -381,10 +374,12 @@ public class ASTToTargetAST {
         }).findFirst();
     }
 
-    private Set<TargetMethod> convert(ClassOrInterface currentClass, Method method) {
-        generics = all.get(0);
-        Set<TargetMethod> result = new HashSet<>();
-        Set<List<MethodParameter>> parameterSet = new HashSet<>();
+    record MethodWithTphs(TargetMethod method, List<SignaturePairTarget> args) {}
+
+    private List<MethodWithTphs> convert(ClassOrInterface currentClass, Method method) {
+        generics = all.getFirst();
+        List<MethodWithTphs> result = new ArrayList<>();
+        this.currentMethod = method;
 
         for (var s : all) {
             generics = s;
@@ -402,19 +397,18 @@ public class ASTToTargetAST {
                 }
             }
 
-            List<MethodParameter> finalParams = params;
-            if (parameterSet.stream().noneMatch(p -> p.equals(finalParams))) {
-                List<MethodParameter> txParams = convert(method.getParameterList(), this.generics.txGenerics);
+            List<MethodParameter> txParams = convert(method.getParameterList(), this.generics.txGenerics);
 
-                var javaMethodGenerics = collectMethodGenerics(currentClass, generics.javaGenerics(), javaGenerics, method);
-                var txMethodGenerics = collectMethodGenerics(currentClass, generics.txGenerics(), txGenerics, method);
+            var javaMethodGenerics = collectMethodGenerics(currentClass, generics.javaGenerics(), javaGenerics, method);
+            var txMethodGenerics = collectMethodGenerics(currentClass, generics.txGenerics(), txGenerics, method);
 
-                var javaSignature = new TargetMethod.Signature(javaMethodGenerics, params, returnType);
-                var txSignature = new TargetMethod.Signature(txMethodGenerics, txParams, convert(method.getReturnType(), this.generics.txGenerics));
-                var newMethod = new TargetMethod(method.modifier, method.name, convert(method.block), javaSignature, txSignature);
-                result.add(newMethod);
-                parameterSet.add(params);
-            }
+            var javaSignature = new TargetMethod.Signature(javaMethodGenerics, params, returnType);
+            var txSignature = new TargetMethod.Signature(txMethodGenerics, txParams, convert(method.getReturnType(), this.generics.txGenerics));
+            var newMethod = new TargetMethod(method.modifier, method.name, convert(method.block), javaSignature, txSignature);
+
+            var concreteParams = tphsInMethods.getOrDefault(method, new HashSet<>()).stream().map(sig -> new SignaturePairTarget(convert(sig.signature), convert(sig.parameter))).toList();
+
+            result.add(new MethodWithTphs(newMethod, concreteParams));
         }
 
         return result;
@@ -486,10 +480,59 @@ public class ASTToTargetAST {
         }
         var filteredParams = new ArrayList<TargetType>();
         for (var i = 0; i < newParams.size(); i++) {
-            if (gep.parameters.get(i) != null)
+            if (i < gep.inParams.size() && gep.inParams.get(i) != null)
                 filteredParams.add(newParams.get(i));
         }
-        return TargetFunNType.fromParams(params, filteredParams);
+        return TargetFunNType.fromParams(params, filteredParams, gep.getReturnType() != null ? 1 : 0);
+    }
+
+    private boolean isSubtype(TargetType test, TargetType other) {
+        var testClass = compiler.getClass(new JavaClassName(test.name()));
+        var otherClass = compiler.getClass(new JavaClassName(other.name()));
+        if (testClass == null) return false;
+        while (testClass != null) {
+            if (testClass.equals(otherClass)) return true;
+            if (testClass.getClassName().equals(new JavaClassName("java.lang.Object"))) break;
+            testClass = compiler.getClass(testClass.getSuperClass().getName());
+        }
+        return false;
+    }
+
+    private boolean isSupertype(TargetType test, TargetType other) {
+        return isSubtype(other, test);
+    }
+
+    private boolean isSubtype(FunNGenerator.GenericParameters test, FunNGenerator.GenericParameters other) {
+        if (test.getArguments().size() != other.getArguments().size()) return false;
+        if (!isSubtype(test.getReturnType(), other.getReturnType())) return false;
+        for (int i = 0; i < test.getArguments().size(); i++) {
+            var arg1 = test.getArguments().get(i);
+            var arg2 = other.getArguments().get(i);
+            if (!isSupertype(arg1, arg2)) return false;
+        }
+        return true;
+    }
+
+    public void generateFunNTypes() {
+        for (var entry : usedFunN.entrySet()) {
+            var gep = entry.getValue();
+            var superInterfaces = usedFunN.values().stream()
+                .filter(g -> !g.equals(gep))
+                .filter(genericParameters -> isSubtype(gep, genericParameters))
+                .map(FunNGenerator::getSpecializedClassName)
+                .toList();
+
+            var code = FunNGenerator.generateSpecializedBytecode(gep, superInterfaces);
+
+            try {
+                classLoader.findClass(entry.getKey());
+            } catch (ClassNotFoundException e) {
+                try {
+                    classLoader.loadClass(code);
+                } catch (LinkageError ignored) {}
+            }
+            auxiliaries.put(entry.getKey(), code);
+        }
     }
 
     protected TargetType convert(RefTypeOrTPHOrWildcardOrGeneric input, GenerateGenerics generics) {
@@ -504,17 +547,16 @@ public class ASTToTargetAST {
                 }
 
                 var params = refType.getParaList().stream().map(type -> {
-                    var res = convert(type, generics);
-                    if (res == null) res = new TargetRefType("java.lang.Void");
-                    return res;
+                    return convert(type, generics);
                 }).toList();
 
                 if (name.matches("Fun\\d+\\$\\$")) { // TODO This seems like a bad idea
-                    var className = FunNGenerator.getSpecializedClassName(FunNGenerator.getArguments(params), FunNGenerator.getReturnType(params));
+                    var returnType = FunNGenerator.getReturnType(params);
+                    var className = FunNGenerator.getSpecializedClassName(FunNGenerator.getArguments(params), returnType);
                     if (!usedFunNSuperTypes.contains(params.size())) {
                         usedFunNSuperTypes.add(params.size());
-                        var code = FunNGenerator.generateSuperBytecode(params.size() - 1);
-                        var superClassName = FunNGenerator.getSuperClassName(params.size() - 1);
+                        var code = FunNGenerator.generateSuperBytecode(params.size() - 1, returnType != null ? 1 : 0);
+                        var superClassName = FunNGenerator.getSuperClassName(params.size() - 1, returnType != null ? 1 : 0);
                         try {
                             classLoader.findClass(superClassName);
                         } catch (ClassNotFoundException e) {
@@ -526,17 +568,8 @@ public class ASTToTargetAST {
                     }
                     FunNGenerator.GenericParameters gep = null;
                     if (!usedFunN.containsKey(className)) {
-                        gep = new FunNGenerator.GenericParameters();
-                        var code = FunNGenerator.generateSpecializedBytecode(FunNGenerator.getArguments(params), FunNGenerator.getReturnType(params), gep);
-                        try {
-                            classLoader.findClass(className);
-                        } catch (ClassNotFoundException e) {
-                            try {
-                                classLoader.loadClass(code);
-                            } catch (LinkageError ignored) {}
-                        }
+                        gep = new FunNGenerator.GenericParameters(params, returnType != null ? 1 : 0);
                         usedFunN.put(className, gep);
-                        auxiliaries.put(className, code);
                     } else {
                         gep = usedFunN.get(className);
                     }

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

@@ -652,14 +652,12 @@ public abstract class GenerateGenerics {
     }
 
     void normalize(Set<Pair> result, Set<Pair> classGenerics, Set<TPH> usedTphs) {
-        outer:
-        for (var tph : usedTphs) {
-            for (var p1 : new HashSet<>(result)) {
-                if (p1 instanceof PairLT ptph && ptph.left.equals(ptph.right))
-                    result.remove(p1); // TODO This is a bit strange
-                if (p1.left.equals(tph)) continue outer;
-            }
+        for (var p1 : new HashSet<>(result)) {
+            if (p1 instanceof PairLT ptph && ptph.left.resolve().equals(ptph.right.resolve()))
+                result.remove(p1); // TODO This is a bit strange
+        }
 
+        for (var tph : usedTphs) {
             if (classGenerics == null || classGenerics.stream().noneMatch((pair) -> pair.left.equals(tph)))
                 addToPairs(result, new PairEQ(tph, ASTToTargetAST.OBJECT));
         }

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

@@ -208,6 +208,11 @@ public class StatementToTargetExpression implements ASTVisitor {
         var isPrivate = false;
         var signature = methodCall.signatureArguments().stream().map(converter::convert).toList();
 
+        // Add used TPHs to containing method
+        for (var i = 0; i < methodCall.signatureArguments().size(); i++) {
+            converter.addSignaturePair(methodCall.signatureArguments().get(i), methodCall.arglist.getArguments().get(i).getType());
+        }
+
         var receiverClass = converter.compiler.getClass(receiverName);
         if (methodCall.receiver instanceof ExpressionReceiver expressionReceiver && expressionReceiver.expr instanceof This) {
             if (receiverClass == null) throw new DebugException("Class " + receiverName + " does not exist!");

src/main/java/de/dhbwstuttgart/target/tree/type/TargetFunNType.java

@@ -4,15 +4,29 @@ import de.dhbwstuttgart.bytecode.FunNGenerator;
 
 import java.util.List;
 
-public record TargetFunNType(String name, List<TargetType> params) implements TargetSpecializedType {
+public record TargetFunNType(String name, List<TargetType> funNParams, List<TargetType> params, int returnArguments) implements TargetSpecializedType {
 
-    public static TargetFunNType fromParams(List<TargetType> params) {
-        return fromParams(params, params);
+    public static TargetFunNType fromParams(List<TargetType> params, int returnArguments) {
+        return fromParams(params, params, returnArguments);
     }
 
-    public static TargetFunNType fromParams(List<TargetType> params, List<TargetType> realParams) {
+    public static TargetFunNType fromParams(List<TargetType> params, List<TargetType> realParams, int returnArguments) {
         var name = FunNGenerator.getSpecializedClassName(FunNGenerator.getArguments(params), FunNGenerator.getReturnType(params));
-        return new TargetFunNType(name, realParams);
+        return new TargetFunNType(name, params, realParams, returnArguments);
+    }
+
+    public String toMethodDescriptor() {
+        var res = "(";
+        for (var i = 0; i < funNParams.size() - 1; i++) {
+            res += "Ljava/lang/Object;";
+        }
+        res += ")";
+        if (returnArguments > 0) {
+            res += "Ljava/lang/Object;";
+        } else {
+            res += "V";
+        }
+        return res;
     }
 
     @Override

src/main/java/de/dhbwstuttgart/target/tree/type/TargetType.java

@@ -53,19 +53,17 @@ public sealed interface TargetType
         };
     }
 
-    static TargetType toTargetType(Class<?> clazz) {
-        if (clazz.isPrimitive()) {
-            if (clazz.equals(boolean.class))    return boolean_;
-            if (clazz.equals(char.class))       return char_;
-            if (clazz.equals(byte.class))       return byte_;
-            if (clazz.equals(short.class))      return short_;
-            if (clazz.equals(int.class))        return int_;
-            if (clazz.equals(long.class))       return long_;
-            if (clazz.equals(float.class))      return float_;
-            if (clazz.equals(double.class))     return double_;
-        }
-        if (clazz.equals(void.class)) return null;
-        return new TargetRefType(clazz.getName());
+    static TargetType toWrapper(TargetType f) {
+        if (f.equals(boolean_))    return Boolean;
+        if (f.equals(char_))       return Char;
+        if (f.equals(byte_))       return Byte;
+        if (f.equals(short_))      return Short;
+        if (f.equals(int_))        return Integer;
+        if (f.equals(long_))       return Long;
+        if (f.equals(float_))      return Float;
+        if (f.equals(double_))     return Double;
+
+        return f;
     }
 
     String toSignature();

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

@@ -877,8 +877,6 @@ public class TYPEStmt implements StatementVisitor {
                                 var clazz = interestingClasses.get(j);
                                 for (int k = 0; k < clazz.getConstructors().size(); k++) {
                                     var constructor = clazz.getConstructors().get(k);
-                                    //Erster Constraint wahrscheinlich unnötig.
-                                    constraintsSet.addUndConstraint(new Pair( clazz.getFieldDecl().get(i).getType(), constructor.getParameterList().getParameterAt(i).getType(), PairOperator.SMALLERDOT, loc(constructor.getParameterList().getParameterAt(i).getOffset())));
                                     constraintsSet.addUndConstraint(new Pair(supPattern.getType(), constructor.getParameterList().getParameterAt(i).getType(), PairOperator.SMALLERDOT, loc(constructor.getParameterList().getParameterAt(i).getOffset())));
 
                                 }

src/test/java/AllgemeinTest.java

@@ -66,7 +66,9 @@ public class AllgemeinTest {
 		//String className = "WildcardList";
 		//String className = "List";
 		//String className = "Box";
-		String className = "GenBox";
+		//String className = "GenBox";
+		//String className = "InnerInf";
+		String className = "Foo";
 		//PL 2019-10-24: genutzt fuer unterschiedliche Tests
 		path = System.getProperty("user.dir")+"/resources/AllgemeinTest/" + className + ".jav";
 		//path = System.getProperty("user.dir")+"/src/test/resources/AllgemeinTest/Overloading_Generics.jav";

src/test/java/TestComplete.java

@@ -696,18 +696,25 @@ public class TestComplete {
     @Ignore("Not implemented")
     @Test
     public void testRecordList() throws Exception {
-        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "recordList.jav");
-        var clazz = classFiles.get("Nil");
-
+        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "SwitchCaseHeritageDetection.jav");
+        var clazz = classFiles.get("SwitchCaseHeritageDetection");
+        var clazzAbst = classFiles.get("NumberOrText");
+        var clazzStringer = classFiles.get("Text");
+        var clazzNumber = classFiles.get("Number");
         var instance = clazz.getDeclaredConstructor().newInstance();
-        var swtch = clazz.getDeclaredMethod("m", Object.class);
+        var swtch = clazz.getDeclaredMethod("main", Object.class);
 
-        //var record = classFiles.get("Rec");
-        //var ctor = record.getDeclaredConstructor(Object.class, Object.class);
-        //var r1 = ctor.newInstance(1, 1);
+        var record = classFiles.get("Cons");
 
 
-        assertEquals(swtch.invoke(instance, null), 2);
+
+        var ctor = record.getDeclaredConstructor(Integer.class, clazzAbst.getConstructor().newInstance().getClass());
+        var r1 = ctor.newInstance(1, clazzStringer.getConstructor().newInstance());
+        var r2 = ctor.newInstance(1, clazzNumber.getConstructor().newInstance());
+
+
+        assertEquals(swtch.invoke(instance, r1), "Second Element is a Text");
+        assertEquals(swtch.invoke(instance, r2), "Second Element is a Number");
     }
 
     @Ignore("Not implemented")
@@ -898,13 +905,6 @@ public class TestComplete {
         var instance = clazz.getDeclaredConstructor().newInstance();
     }
 
-    @Test
-    public void testLamRunnable() throws Exception {
-        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "LamRunnable.jav");
-        var clazz = classFiles.get("LamRunnable");
-        var instance = clazz.getDeclaredConstructor().newInstance();
-    }
-
     @Test
     public void testAccess() throws Exception {
         var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Access.jav");
@@ -1164,6 +1164,13 @@ public class TestComplete {
         var instance = clazz.getDeclaredConstructor().newInstance();
     }
 
+    @Test
+    public void testBug332() throws Exception {
+        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug332.jav");
+        var clazz = classFiles.get("Bug332");
+        var instance = clazz.getDeclaredConstructor().newInstance();
+    }
+
     @Test
     public void testBug333() throws Exception {
         var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug333.jav");
@@ -1171,6 +1178,14 @@ public class TestComplete {
         var instance = clazz.getDeclaredConstructor().newInstance();
     }
 
+    @Test
+    public void testBug337() throws Exception {
+        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug337.jav");
+        var clazz = classFiles.get("Bug337");
+        var instance = clazz.getDeclaredConstructor().newInstance();
+        clazz.getDeclaredMethod("main").invoke(instance);
+    }
+
     @Test
     public void testBug338() throws Exception {
         var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug338.jav");

src/test/java/targetast/TestCodegen.java

@@ -22,7 +22,6 @@ import static org.junit.Assert.*;
 import org.objectweb.asm.Opcodes;
 
 import java.io.File;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -61,6 +60,8 @@ public class TestCodegen {
                 }
             }).collect(Collectors.toMap(Class::getName, Function.identity())));
 
+            converter.generateFunNTypes();
+
             for (var entry : converter.auxiliaries.entrySet()) {
                 writeClassFile(entry.getKey(), entry.getValue());
             }
@@ -84,9 +85,6 @@ public class TestCodegen {
     public static Class<?> generateClass(TargetStructure clazz, IByteArrayClassLoader classLoader, ASTToTargetAST converter) throws IOException {
         Codegen codegen = new Codegen(clazz, converter.compiler, converter);
         var code = codegen.generate();
-        try (FileOutputStream fos = new FileOutputStream("C:\\Users\\ruben\\Desktop\\asd\\test.class")) {
-            fos.write(code);
-        }
         writeClassFile(clazz.qualifiedName().getClassName(), code);
         return classLoader.loadClass(code);
     }
@@ -108,6 +106,8 @@ public class TestCodegen {
             }
         }).collect(Collectors.toMap(Class::getName, Function.identity()));
 
+        converter.generateFunNTypes();
+
         for (var entry : converter.auxiliaries.entrySet()) {
             writeClassFile(entry.getKey(), entry.getValue());
         }
@@ -220,19 +220,19 @@ public class TestCodegen {
     public void testClassicSwitch() throws Exception {
         var targetClass = new TargetClass(Opcodes.ACC_PUBLIC , new JavaClassName("SwitchClassic"));
         targetClass.addMethod(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "switchClassic", List.of(new MethodParameter(TargetType.Integer, "i")), TargetType.Integer, new TargetBlock(List.of(
-            new TargetVarDecl(TargetType.Integer, "res", null),
-            new TargetSwitch(new TargetLocalVar(TargetType.Integer, "i"), List.of(
-                new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(10)), new TargetBlock(
-                    List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(0)), new TargetBreak())
-                )),
-                new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(15), new TargetLiteral.IntLiteral(20)), new TargetBlock(List.of())),
-                new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(30)), new TargetBlock(
-                    List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(1)), new TargetBreak())
-                ))
-            ), new TargetSwitch.Case(new TargetBlock(
-                List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(2)), new TargetBreak())
-            ), false)),
-            new TargetReturn(new TargetLocalVar(TargetType.Integer, "res"))
+                new TargetVarDecl(TargetType.Integer, "res", null),
+                new TargetSwitch(new TargetLocalVar(TargetType.Integer, "i"), List.of(
+                        new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(10)), new TargetBlock(
+                                List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(0)), new TargetBreak())
+                        )),
+                        new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(15), new TargetLiteral.IntLiteral(20)), new TargetBlock(List.of())),
+                        new TargetSwitch.Case(List.of(new TargetLiteral.IntLiteral(30)), new TargetBlock(
+                                List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(1)), new TargetBreak())
+                        ))
+                ), new TargetSwitch.Case(new TargetBlock(
+                        List.of(new TargetAssign(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "res"), new TargetLiteral.IntLiteral(2)), new TargetBreak())
+                ), false)),
+                new TargetReturn(new TargetLocalVar(TargetType.Integer, "res"))
         )));
 
         var clazz = generateClass(targetClass, new ByteArrayClassLoader());
@@ -248,22 +248,22 @@ public class TestCodegen {
     public void testTypeSwitch() throws Exception {
         var targetClass = new TargetClass(Opcodes.ACC_PUBLIC, new JavaClassName("SwitchEnhanced"));
         targetClass.addMethod(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "switchType", List.of(new MethodParameter(TargetType.Object, "obj")), TargetType.Integer, new TargetBlock(List.of(
-            new TargetReturn(new TargetSwitch(new TargetLocalVar(TargetType.Object, "obj"), List.of(
-                new TargetSwitch.Case(List.of(new TargetTypePattern(TargetType.String, "aString")), new TargetBlock(
-                    List.of(new TargetYield(new TargetLiteral.IntLiteral(0)))
-                ), false),
-                new TargetSwitch.Case(List.of(
-                    new TargetGuard(new TargetTypePattern(TargetType.Integer, "i"), new TargetBinaryOp.Less(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "i"), new TargetLiteral.IntLiteral(10)))
-                ), new TargetBlock(
-                    List.of(new TargetLiteral.IntLiteral(3))
-                ), true),
-                new TargetSwitch.Case(List.of(new TargetTypePattern(TargetType.Integer, "anInteger")), new TargetBlock(
-                    List.of(new TargetLiteral.IntLiteral(1))
-                ), true)
-            ), new TargetSwitch.Case(new TargetBlock(
-                    List.of(new TargetLiteral.IntLiteral(2))
-            ), true), TargetType.Integer)
-        ))));
+                new TargetReturn(new TargetSwitch(new TargetLocalVar(TargetType.Object, "obj"), List.of(
+                        new TargetSwitch.Case(List.of(new TargetTypePattern(TargetType.String, "aString")), new TargetBlock(
+                                List.of(new TargetYield(new TargetLiteral.IntLiteral(0)))
+                        ), false),
+                        new TargetSwitch.Case(List.of(
+                                new TargetGuard(new TargetTypePattern(TargetType.Integer, "i"), new TargetBinaryOp.Less(TargetType.Integer, new TargetLocalVar(TargetType.Integer, "i"), new TargetLiteral.IntLiteral(10)))
+                        ), new TargetBlock(
+                                List.of(new TargetLiteral.IntLiteral(3))
+                        ), true),
+                        new TargetSwitch.Case(List.of(new TargetTypePattern(TargetType.Integer, "anInteger")), new TargetBlock(
+                                List.of(new TargetLiteral.IntLiteral(1))
+                        ), true)
+                ), new TargetSwitch.Case(new TargetBlock(
+                        List.of(new TargetLiteral.IntLiteral(2))
+                ), true), TargetType.Integer)
+                ))));
         var clazz = generateClass(targetClass, new ByteArrayClassLoader());
         var m = clazz.getDeclaredMethod("switchType", Object.class);
         assertEquals(m.invoke(null, "String"), 0);
@@ -277,7 +277,7 @@ public class TestCodegen {
     public void testLambda() throws Exception {
         var classLoader = new ByteArrayClassLoader();
         // var fun = classLoader.loadClass(Path.of(System.getProperty("user.dir"), "src/test/java/targetast/Fun1$$.class"));
-        var interfaceType = TargetFunNType.fromParams(List.of(TargetType.Integer));
+        var interfaceType = TargetFunNType.fromParams(List.of(TargetType.Integer), 1);
 
         var targetClass = new TargetClass(Opcodes.ACC_PUBLIC, new JavaClassName("CGLambda"));
         targetClass.addConstructor(Opcodes.ACC_PUBLIC, List.of(), new TargetBlock(List.of(new TargetMethodCall(null, new TargetSuper(TargetType.Object), List.of(), TargetType.Object, "<init>", false, false, false))));