code: public boolean next(ByteBuffer key, SortedMap<ByteBuffer, Cell> value) throws IOException
      {
          if (this.nextKeyValue())
          {
              key.clear();
              key.put(this.getCurrentKey().duplicate());
              key.flip();
  
              value.clear();
              value.putAll(this.getCurrentValue());
  
              return true;
          }
          return false;
      }
docs: and ColumnFamilyRecordReader don't support them, it should be fine for now.