@Override
      public void process(boolean isAdded, int objectId) throws IOException {
        writer.stepIn(IonType.STRUCT);
        writer.setFieldName(OBJECT_ID_FIELD);
        writer.writeInt(objectId);
        if (isAdded) {
          writer.setFieldName("_type");
          writer.writeString(ReferenceNode.class.getSimpleName());
          writeDependencyCommonFields(writer, node);
        }
        writer.stepOut();
      }
@Override
      public void process(boolean isAdded, int objectId)