code: @Override
      public boolean resetSupported() {
          boolean sup = true;
  
          for (val i: iterators)
              if (!i.resetSupported()) {
                  sup = false;
                  break;
              }
  
          return sup;
      }
docs: Is resetting supported by this DataSetIterator? Many DataSetIterators do support resetting,
  but some don't
  
  @return true if reset method is supported; false otherwise