diff --git a/src/main/java/nl/sander/beejava/CompiledClass.java b/src/main/java/nl/sander/beejava/CompiledClass.java
index eb2efb3..c6cec76 100644
--- a/src/main/java/nl/sander/beejava/CompiledClass.java
+++ b/src/main/java/nl/sander/beejava/CompiledClass.java
@@ -28,14 +28,14 @@ public class CompiledClass {
         return thisClass.getIndex();
     }
 
-    public ClassEntry superClass() {
+    public ClassEntry addSuperClass() {
         if (superClass == null) {
             superClass = createClassEntry(beeClass.getSuperClass().getName());
         }
         return superClass;
     }
 
-    public ClassEntry thisClass() {
+    public ClassEntry addThisClass() {
         if (thisClass == null) {
             thisClass = createClassEntry(internalName(beeClass.getName()));
         }
@@ -58,11 +58,7 @@ public class CompiledClass {
         constantTree.add(interfaceEntry);
     }
 
-    public void setThisClass() {
-        constantTree.add(thisClass());
-    }
-
-    public void setInterfaces() {
+    public void addInterfaces() {
         beeClass.getInterfaces().forEach(interfase -> {
             ClassEntry interfaceEntry = new ClassEntry(new Utf8Entry(internalName(interfase.getName())));
             addInterface(interfaceEntry);
@@ -70,6 +66,12 @@ public class CompiledClass {
         });
     }
 
+    public void addFields() {
+        beeClass.getFields().forEach(field -> {
+            // TODO
+        });
+    }
+
     private ClassEntry createClassEntry(String name) {
         return new ClassEntry(new Utf8Entry(internalName(name)));
     }
diff --git a/src/main/java/nl/sander/beejava/Compiler.java b/src/main/java/nl/sander/beejava/Compiler.java
index 17adf48..34d3f63 100644
--- a/src/main/java/nl/sander/beejava/Compiler.java
+++ b/src/main/java/nl/sander/beejava/Compiler.java
@@ -27,11 +27,12 @@ public class Compiler {
     public CompiledClass compile(BeeClass beeClass) {
         compiledClass = new CompiledClass(beeClass);
         beeClass.getConstructors().forEach(this::updateConstantPool);
-        // TODO update constantTree for fields ?
-        // TODO update constantTree for methods
+        // TODO update constant pool for fields ?
+        // TODO update constant pool for methods
 
-        compiledClass.setThisClass();
-        compiledClass.setInterfaces();
+        compiledClass.addThisClass();
+        compiledClass.addInterfaces();
+        compiledClass.addFields();
 
         return compiledClass;
     }
@@ -46,19 +47,19 @@ public class Compiler {
      */
     private void updateConstantPool(CodeLine codeline) {
         if (codeline.hasMethod()) {
-            addMethod(codeline);
+            addMethodToConstantPool(codeline);
         }
 
         if (codeline.hasField()) {
-            addField(codeline);
+            addFieldToConstantPool(codeline);
         }
     }
 
-    private void addMethod(CodeLine codeline) {
+    private void addMethodToConstantPool(CodeLine codeline) {
         compiledClass.addConstantPoolEntry(new MethodRefEntry(getOrCreateClassEntry(codeline), createMethodNameAndType(codeline)));
     }
 
-    private void addField(CodeLine codeline) {
+    private void addFieldToConstantPool(CodeLine codeline) {
         compiledClass.addConstantPoolEntry(new FieldRefEntry(getOrCreateClassEntry(codeline), createFieldNameAndType(codeline)));
     }
 
@@ -72,9 +73,10 @@ public class Compiler {
 
     private ClassEntry getOrCreateClassEntry(CodeLine codeline) {
         if (codeline.getRef() == Ref.SUPER) {
-            return compiledClass.superClass();
+            return compiledClass.addSuperClass();
+
         } else if (codeline.getRef() == Ref.THIS) {
-            return compiledClass.thisClass();
+            return compiledClass.addThisClass();
         }
         //TODO other cases
         throw new RuntimeException("shouldn't be here");
diff --git a/src/test/java/nl/sander/beejava/CompilerTests.java b/src/test/java/nl/sander/beejava/CompilerTests.java
index dff6d77..30d9780 100644
--- a/src/test/java/nl/sander/beejava/CompilerTests.java
+++ b/src/test/java/nl/sander/beejava/CompilerTests.java
@@ -62,38 +62,4 @@ public class CompilerTests {
         Utf8Entry type = (Utf8Entry) child5;
         assertEquals("()V", type.getUtf8());
     }
-
-    private BeeClass createClassWithIntField() {
-        BeeField intField = BeeField.builder()
-                .withAccessFlags(FieldAccessFlag.PRIVATE)
-                .withType(int.class)
-                .withName("intField")
-                .build();
-
-        BeeParameter intValueParameter = BeeParameter.create(int.class, "intValue");
-
-        BeeConstructor constructor = BeeConstructor.builder()
-                .withAccessFlags(MethodAccessFlag.PUBLIC)
-                .withFormalParameters(intValueParameter)
-                .withCode(
-                        line(0, LOAD, Ref.THIS),
-                        line(1, INVOKE, Ref.SUPER, "<init>", "()"),
-                        line(2, LOAD, Ref.THIS),
-                        line(3, LOAD, intValueParameter),
-                        line(4, PUT, intField),
-                        line(5, RETURN))
-                .build();
-
-        return BeeClass.builder()
-                .withClassFileVersion(Version.V14)
-                .withPackage("nl.sander.beejava.test")
-                .withAccessFlags(PUBLIC)
-                .withSimpleName("IntBean")
-                .withSuperClass(Object.class)
-                .withFields(intField)
-                .withConstructors(constructor)
-                .build();
-    }
-
-
 }
diff --git a/src/test/java/nl/sander/beejava/TestData.java b/src/test/java/nl/sander/beejava/TestData.java
index cb133cd..00c3a86 100644
--- a/src/test/java/nl/sander/beejava/TestData.java
+++ b/src/test/java/nl/sander/beejava/TestData.java
@@ -1,9 +1,7 @@
 package nl.sander.beejava;
 
-import nl.sander.beejava.api.BeeClass;
-import nl.sander.beejava.api.BeeConstructor;
-import nl.sander.beejava.api.Ref;
-import nl.sander.beejava.api.Version;
+import nl.sander.beejava.api.*;
+import nl.sander.beejava.flags.FieldAccessFlag;
 import nl.sander.beejava.flags.MethodAccessFlag;
 
 import java.io.Serializable;
@@ -20,7 +18,7 @@ public class TestData {
                 .withAccessFlags(PUBLIC)
                 .withSimpleName("EmptyBean")
                 .withSuperClass(Object.class) // Not mandatory, like in java sourcecode
-                .withConstructors(getBeeConstructor()) // There's no default constructor in beejava. The user must always add them
+                .withConstructors(createConstructor()) // There's no default constructor in beejava. The user must always add them
                 .build();
     }
 
@@ -32,18 +30,49 @@ public class TestData {
                 .withSimpleName("EmptyBean")
                 .withSuperClass(Object.class) // Not mandatory, like in java sourcecode
                 .withInterfaces(Serializable.class)
-                .withConstructors(getBeeConstructor()) // There's no default constructor in beejava. The user must always add them
+                .withConstructors(createConstructor()) // There's no default constructor in beejava. The user must always add them
                 .build();
     }
 
-    private static BeeConstructor getBeeConstructor() {
+    public static BeeClass createClassWithIntField() {
+        BeeField intField = BeeField.builder()
+                .withAccessFlags(FieldAccessFlag.PRIVATE)
+                .withType(int.class)
+                .withName("intField")
+                .build();
+
+        BeeParameter intValueParameter = BeeParameter.create(int.class, "intValue");
+
         BeeConstructor constructor = BeeConstructor.builder()
+                .withAccessFlags(MethodAccessFlag.PUBLIC)
+                .withFormalParameters(intValueParameter)
+                .withCode(
+                        line(0, LOAD, Ref.THIS),
+                        line(1, INVOKE, Ref.SUPER, "<init>", "()"),
+                        line(2, LOAD, Ref.THIS),
+                        line(3, LOAD, intValueParameter),
+                        line(4, PUT, intField),
+                        line(5, RETURN))
+                .build();
+
+        return BeeClass.builder()
+                .withClassFileVersion(Version.V14)
+                .withPackage("nl.sander.beejava.test")
+                .withAccessFlags(PUBLIC)
+                .withSimpleName("IntBean")
+                .withSuperClass(Object.class)
+                .withFields(intField)
+                .withConstructors(constructor)
+                .build();
+    }
+
+    private static BeeConstructor createConstructor() {
+        return BeeConstructor.builder()
                 .withAccessFlags(MethodAccessFlag.PUBLIC)
                 .withCode(
                         line(0, LOAD, Ref.THIS),
                         line(1, INVOKE, Ref.SUPER, "<init>", "()"),
                         line(5, RETURN))
                 .build();
-        return constructor;
     }
 }