@Override
  public void addLastBloomKey(Writer writer) throws IOException {
    if (this.getLastCell() != null) {
      byte[] key = CellUtil.copyRow(this.getLastCell());
      writer.appendFileInfo(LAST_BLOOM_KEY, key);
    }
  }
Handles ROW bloom related context. It works with both ByteBufferedCell and byte[] backed cells
hbase-server/src/main/java/org/apache/hadoop/hbase/util/RowBloomContext.java