code: public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
     {
  
        if (in.readInt() == 1)
        {
           byte[] buf = new byte[in.readInt()];
           in.readFully(buf);
           systemId = new String(buf, Constants.DEFAULT_ENCODING);
        }
  
        int listSize = in.readInt();
        for (int i = 0; i < listSize; i++)
        {
           changesLogs.add((PlainChangesLog)in.readObject());
        }
     }
docs: {@inheritDoc}