Program: 63645
Project: 63645
Buggy source:
private void checkForCallbackMethods(){
  for (  JavaClass next : typeInfoClasses) {
    if (next == null) {
      continue;
    }
    JavaClass unmarshallerCls=helper.getJavaClass(Unmarshaller.class);
    JavaClass marshallerCls=helper.getJavaClass(Marshaller.class);
    JavaClass objectCls=helper.getJavaClass(Object.class);
    JavaClass[] unmarshalParams=new JavaClass[]{unmarshallerCls,objectCls};
    JavaClass[] marshalParams=new JavaClass[]{marshallerCls};
    UnmarshalCallback unmarshalCallback=null;
    MarshalCallback marshalCallback=null;
    if (next.getMethod("String_Node_Str",unmarshalParams) != null) {
      unmarshalCallback=new UnmarshalCallback();
      unmarshalCallback.setDomainClassName(next.getQualifiedName());
      unmarshalCallback.setHasBeforeUnmarshalCallback();
    }
    if (next.getMethod("String_Node_Str",unmarshalParams) != null) {
      if (unmarshalCallback == null) {
        unmarshalCallback=new UnmarshalCallback();
        unmarshalCallback.setDomainClassName(next.getQualifiedName());
      }
      unmarshalCallback.setHasAfterUnmarshalCallback();
    }
    if (unmarshalCallback != null) {
      if (this.unmarshalCallbacks == null) {
        this.unmarshalCallbacks=new HashMap<String,UnmarshalCallback>();
      }
      unmarshalCallbacks.put(next.getQualifiedName(),unmarshalCallback);
    }
    if (next.getMethod("String_Node_Str",marshalParams) != null) {
      marshalCallback=new MarshalCallback();
      marshalCallback.setDomainClassName(next.getQualifiedName());
      marshalCallback.setHasBeforeMarshalCallback();
    }
    if (next.getMethod("String_Node_Str",marshalParams) != null) {
      if (marshalCallback == null) {
        marshalCallback=new MarshalCallback();
        marshalCallback.setDomainClassName(next.getQualifiedName());
      }
      marshalCallback.setHasAfterMarshalCallback();
    }
    if (marshalCallback != null) {
      if (this.marshalCallbacks == null) {
        this.marshalCallbacks=new HashMap<String,MarshalCallback>();
      }
      marshalCallbacks.put(next.getQualifiedName(),marshalCallback);
    }
  }
}

Fixed version (ground truth):
private void checkForCallbackMethods(){
  JavaClass unmarshallerCls=helper.getJavaClass(Unmarshaller.class);
  JavaClass marshallerCls=helper.getJavaClass(Marshaller.class);
  JavaClass objectCls=helper.getJavaClass(Object.class);
  JavaClass[] unmarshalParams=new JavaClass[]{unmarshallerCls,objectCls};
  JavaClass[] marshalParams=new JavaClass[]{marshallerCls};
  for (  JavaClass next : typeInfoClasses) {
    if (next == null) {
      continue;
    }
    UnmarshalCallback unmarshalCallback=null;
    MarshalCallback marshalCallback=null;
    if (next.getMethod("String_Node_Str",unmarshalParams) != null) {
      unmarshalCallback=new UnmarshalCallback();
      unmarshalCallback.setDomainClassName(next.getQualifiedName());
      unmarshalCallback.setHasBeforeUnmarshalCallback();
    }
    if (next.getMethod("String_Node_Str",unmarshalParams) != null) {
      if (unmarshalCallback == null) {
        unmarshalCallback=new UnmarshalCallback();
        unmarshalCallback.setDomainClassName(next.getQualifiedName());
      }
      unmarshalCallback.setHasAfterUnmarshalCallback();
    }
    if (unmarshalCallback != null) {
      if (this.unmarshalCallbacks == null) {
        this.unmarshalCallbacks=new HashMap<String,UnmarshalCallback>();
      }
      unmarshalCallbacks.put(next.getQualifiedName(),unmarshalCallback);
    }
    if (next.getMethod("String_Node_Str",marshalParams) != null) {
      marshalCallback=new MarshalCallback();
      marshalCallback.setDomainClassName(next.getQualifiedName());
      marshalCallback.setHasBeforeMarshalCallback();
    }
    if (next.getMethod("String_Node_Str",marshalParams) != null) {
      if (marshalCallback == null) {
        marshalCallback=new MarshalCallback();
        marshalCallback.setDomainClassName(next.getQualifiedName());
      }
      marshalCallback.setHasAfterMarshalCallback();
    }
    if (marshalCallback != null) {
      if (this.marshalCallbacks == null) {
        this.marshalCallbacks=new HashMap<String,MarshalCallback>();
      }
      marshalCallbacks.put(next.getQualifiedName(),marshalCallback);
    }
  }
}