private void ensureCardsIsMutable() {
        if (!((bitField0_ & 0x00000001) != 0)) {
          cards_ = new java.util.ArrayList<DriverCard>(cards_);
          bitField0_ |= 0x00000001;
         }
      }
<code>.com.alibaba.fastjson2.dubbo.DriverCard card = 16;</code>
core/src/test/java/com/alibaba/fastjson2/dubbo/GoogleProtobufBasic.java