@Override
    public void readFields(DataInput in) throws IOException {
      super.readFields(in);
      _isShrinked = in.readBoolean();
      if (_isShrinked) {
        shrinkedLength = in.readLong();
      }
    }
Base implemention for shims against secure Hadoop 0.20.3/0.23.
shims/common/src/main/java/org/apache/hadoop/hive/shims/HadoopShimsSecure.java