private com.google.protobuf.SingleFieldBuilder<
          JOutPiqi.callback_response, JOutPiqi.callback_response.Builder, JOutPiqi.callback_responseOrBuilder> 
          getResponseFieldBuilder() {
        if (responseBuilder_ == null) {
          responseBuilder_ = new com.google.protobuf.SingleFieldBuilder<
              JOutPiqi.callback_response, JOutPiqi.callback_response.Builder, JOutPiqi.callback_responseOrBuilder>(
                  response_,
                  getParentForChildren(),
                  isClean());
          response_ = null;
        }
        return responseBuilder_;
      }