@Override
  public void serialize(T t, OutputStream outputStream) throws IOException {
    serializer.serialize(t, logBufferStream);
    // write the length of plan data
    logLengthBuffer.putInt(logBufferStream.size());
    outputStream.write(logLengthBuffer.array());
    // write a long to keep compatible with old version (CRC32 code)
    logBufferStream.write(PLACE_HOLDER);
    logBufferStream.writeTo(outputStream);
    // clear buffer
    logLengthBuffer.clear();
    logBufferStream.reset();
  }
This classed is used for keep mlog compatible with that of 0.14 snapshot versions. The element T
will be serialized to OutputStream as format: content data length (4B) + content data (var
length) + validation code (long). The validation code will be filled by a meaningless long value.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/schemaengine/schemaregion/logfile/FakeCRC32Serializer.java