private com.google.protobuf.RepeatedFieldBuilder<
          org.bwapi.proxy.messages.GameMessages.UnitTypeIntPair, org.bwapi.proxy.messages.GameMessages.UnitTypeIntPair.Builder, org.bwapi.proxy.messages.GameMessages.UnitTypeIntPairOrBuilder> 
          getRequiredUnitsFieldBuilder() {
        if (requiredUnitsBuilder_ == null) {
          requiredUnitsBuilder_ = new com.google.protobuf.RepeatedFieldBuilder<
              org.bwapi.proxy.messages.GameMessages.UnitTypeIntPair, org.bwapi.proxy.messages.GameMessages.UnitTypeIntPair.Builder, org.bwapi.proxy.messages.GameMessages.UnitTypeIntPairOrBuilder>(
                  requiredUnits_,
                  ((bitField0_ & 0x00000040) == 0x00000040),
                  getParentForChildren(),
                  isClean());
          requiredUnits_ = null;
        }
        return requiredUnitsBuilder_;
      }