private com.google.protobuf.SingleFieldBuilderV3<
          DriverCard, DriverCard.Builder, DriverCardOrBuilder>
          getCardFieldBuilder() {
        if (cardBuilder_ == null) {
          cardBuilder_ = new com.google.protobuf.SingleFieldBuilderV3<
              DriverCard, DriverCard.Builder, DriverCardOrBuilder>(
                  getCard(),
                  getParentForChildren(),
                  isClean());
          card_ = null;
        }
        return cardBuilder_;
      }
<code>.com.alibaba.fastjson2.dubbo.DriverCard card = 16;</code>
core/src/test/java/com/alibaba/fastjson2/dubbo/GoogleProtobufBasic.java