code: public TransactionChangesLog read(ObjectReader in) throws UnknownClassIdException, IOException
     {
  
        // read id
        int key;
        if ((key = in.readInt()) != SerializationConstants.TRANSACTION_CHANGES_LOG)
        {
           throw new UnknownClassIdException("There is unexpected class [" + key + "]");
        }
  
        TransactionChangesLog log = new TransactionChangesLog();
        if (in.readByte() == SerializationConstants.NOT_NULL_DATA)
        {
           log.setSystemId(in.readString());
        }
  
        while (in.readByte() == SerializationConstants.NOT_NULL_DATA)
        {
           PlainChangesLogReader rdr = new PlainChangesLogReader(holder, spoolConfig);
           PlainChangesLog pl = rdr.read(in);
           log.addLog(pl);
        }
  
        return log;
     }
docs: Read and set TransactionChangesLog data.
  
  @param in ObjectReader.
  @return TransactionChangesLog object.
  @throws UnknownClassIdException If read Class ID is not expected or do not
  exist.
  @throws IOException If an I/O error has occurred.