@Override
  protected boolean shouldStop(Cell currentRowCell) {
    if (currentRowCell == null) {
      return true;
    }
    if (stopRow == null || Bytes.equals(stopRow, HConstants.EMPTY_START_ROW)) {
      return false;
    }
    int c = comparator.compareRows(currentRowCell, stopRow, 0, stopRow.length);
    return c < 0 || (c == 0 && !includeStopRow);
  }
ReversibleRegionScannerImpl extends from RegionScannerImpl, and is used to support reversed
scanning.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ReversedRegionScannerImpl.java