code: public boolean isSet(_Fields field) {
      if (field == null) {
        throw new IllegalArgumentException();
      }
  
      switch (field) {
      case NIMBUS_MASTER:
        return is_set_nimbusMaster();
      case NIMBUS_SLAVES:
        return is_set_nimbusSlaves();
      case SUPERVISOR_NUM:
        return is_set_supervisorNum();
      case TOTAL_PORT_NUM:
        return is_set_totalPortNum();
      case USED_PORT_NUM:
        return is_set_usedPortNum();
      case FREE_PORT_NUM:
        return is_set_freePortNum();
      case VERSION:
        return is_set_version();
      }
      throw new IllegalStateException();
    }
docs: Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise