public Builder addLoadedUnits(org.bwapi.proxy.messages.GameMessages.UnitId value) {
        if (loadedUnitsBuilder_ == null) {
          if (value == null) {
            throw new NullPointerException();
          }
          ensureLoadedUnitsIsMutable();
          loadedUnits_.add(value);
          onChanged();
        } else {
          loadedUnitsBuilder_.addMessage(value);
        }
        return this;
      }