docs: @Override
      public final boolean isFieldNameSet()
      {
          if (_field_name_type != null) {
              switch (_field_name_type) {
              case STRING:
                  return _field_name != null;
              case INT:
                  return _field_name_sid >= 0;
              default:
                  break;
              }
          }
          return false;
      }