Start working on the code generator

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

@@ -0,0 +1,57 @@
+package de.dhbwstuttgart.target.bytecode;
+
+import de.dhbwstuttgart.target.tree.TargetClass;
+import de.dhbwstuttgart.target.tree.TargetConstructor;
+import de.dhbwstuttgart.target.tree.TargetField;
+import de.dhbwstuttgart.target.tree.TargetMethod;
+import de.dhbwstuttgart.target.tree.expression.TargetBlock;
+import de.dhbwstuttgart.target.tree.type.TargetType;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.MethodVisitor;
+
+import static org.objectweb.asm.Opcodes.*;
+
+public class Codegen {
+    private TargetClass clazz;
+    private ClassWriter cw;
+
+    public Codegen(TargetClass clazz) {
+        this.clazz = clazz;
+        this.cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
+    }
+
+    private void generateBlock(MethodVisitor mv, TargetBlock block) {
+
+    }
+
+    private void generateField(TargetField field) {
+        cw.visitField(field.access(), field.name(), field.getDescriptor(), null, null);
+    }
+
+    private void generateConstructor(TargetConstructor constructor) {
+        MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, "<init>", constructor.getDescriptor(), null, null);
+        mv.visitEnd();
+    }
+
+    private void generateMethod(TargetMethod method) {
+        // TODO Access modifier
+        MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, method.name(), method.getDescriptor(), null, null);
+        generateBlock(mv, method.block());
+        mv.visitMaxs(0, 0);
+        mv.visitEnd();
+    }
+
+    public byte[] generate() {
+        // TODO Access modifier and signature
+        cw.visit(V12, ACC_PUBLIC, clazz.qualifiedName(),
+                null, clazz.superType().toSignature(),
+                clazz.implementingInterfaces().stream().map(TargetType::toSignature).toArray(String[]::new)
+        );
+        clazz.fields().forEach(this::generateField);
+        clazz.constructors().forEach(this::generateConstructor);
+        clazz.methods().forEach(this::generateMethod);
+
+        cw.visitEnd();
+        return cw.toByteArray();
+    }
+}

src/main/java/de/dhbwstuttgart/target/tree/TargetConstructor.java

@@ -3,5 +3,10 @@ package de.dhbwstuttgart.target.tree;
 import java.util.List;
 
 public record TargetConstructor(List<MethodParameter> parameterTypes) {
+
+    public String getDescriptor() {
+        // TODO
+        return null;
+    }
 }
 

src/main/java/de/dhbwstuttgart/target/tree/TargetField.java

@@ -2,6 +2,10 @@ package de.dhbwstuttgart.target.tree;
 
 import de.dhbwstuttgart.target.tree.type.TargetType;
 
-public record TargetField(TargetType type, String name) {
+public record TargetField(int access, TargetType type, String name) {
+    public String getDescriptor() {
+        // TODO
+        return null;
+    }
 }
 

src/main/java/de/dhbwstuttgart/target/tree/TargetMethod.java

@@ -5,5 +5,9 @@ import de.dhbwstuttgart.target.tree.expression.TargetBlock;
 import java.util.List;
 
 public record TargetMethod(String name, List<MethodParameter> parameterTypes, TargetBlock block) {
+    public String getDescriptor() {
+        // TODO
+        return null;
+    }
 }
 

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

@@ -5,4 +5,8 @@ import de.dhbwstuttgart.target.tree.type.TargetType;
 import java.util.List;
 
 public record TargetRefType(String name, List<TargetType> params) implements TargetType {
+    @Override
+    public String toSignature() {
+        return this.name;
+    }
 }

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

@@ -2,4 +2,6 @@ package de.dhbwstuttgart.target.tree.type;
 
 public sealed interface TargetType
         permits TargetExtendsWildcard, TargetFunNType, TargetGenericType, TargetRefType, TargetSuperWildcard {
+
+    public String toSignature();
 }