public long getTimestamp() {
    return timestamp;
  }
@return a long array whose length is 3, the first long value is tsfile timestamp, the second
    long value is tsfile version, the third long value is compaction version , high 32 bit is
    in-space compaction count, low 32 bit is cross-space compaction count
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/tsfile/TsFileID.java