code: private void processFields() {
      List<Field> fields = getAllFields();
      for (Field field : fields) {
        if (field.isAnnotationPresent(Identifier.class)) {
          processIdentifierField(field);
        } else if (field.isAnnotationPresent(Key.class)) {
          processKeyField(field);
        } else if (field.isAnnotationPresent(ParentKey.class)) {
          processParentKeyField(field);
        } else if (field.isAnnotationPresent(Embedded.class)) {
          processEmbeddedField(field);
        } else {
          processField(field);
        }
      }
    }
docs: Processes the fields defined in this entity and updates the metadata.