@Override
  public int hashCode() {
    int result = Bytes.hashCode(this.encodedRegionName);
    result = (int) (result ^ getSequenceId());
    result = (int) (result ^ this.writeTime);
    return result;
  }
@return the cluster id on which the change has originated. It there is no such cluster, it
        returns DEFAULT_CLUSTER_ID (cases where replication is not enabled)
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALKeyImpl.java