public Builder setRequiredUnits(
          int index, org.bwapi.proxy.messages.GameMessages.UnitTypeIntPair.Builder builderForValue) {
        if (requiredUnitsBuilder_ == null) {
          ensureRequiredUnitsIsMutable();
          requiredUnits_.set(index, builderForValue.build());
          onChanged();
        } else {
          requiredUnitsBuilder_.setMessage(index, builderForValue.build());
        }
        return this;
      }