code: private boolean fetchChunk() throws IOException {
      try {
        ColumnQuery<T, Long, byte[]> query = HFactory.createColumnQuery(keyspace, rowKeySerializer, LongSerializer.get(), BytesArraySerializer.get());
        QueryResult<HColumn<Long, byte[]>> result = query.setColumnFamily(cf).setKey(key).setName(chunkPos).execute();
        HColumn<Long, byte[]> column = result.get();
        if (column != null) {
          chunk = column.getValue();
          chunkPos++;
          pos = 0;
  
          return true;
        } else {
          return false;
        }
      } catch (HectorException e) {
        throw new IOException("Unable to read data", e);
      }
    }
docs: Fetch the next chunk.
  
  @return exists if there was a chunk to fetch.
  @throws IOException