private com.google.protobuf.SingleFieldBuilder<
          JInPiqi.handle_user_join, JInPiqi.handle_user_join.Builder, JInPiqi.handle_user_joinOrBuilder> 
          getHandleUserJoinFieldBuilder() {
        if (handleUserJoinBuilder_ == null) {
          handleUserJoinBuilder_ = new com.google.protobuf.SingleFieldBuilder<
              JInPiqi.handle_user_join, JInPiqi.handle_user_join.Builder, JInPiqi.handle_user_joinOrBuilder>(
                  handleUserJoin_,
                  getParentForChildren(),
                  isClean());
          handleUserJoin_ = null;
        }
        return handleUserJoinBuilder_;
      }