code: @Trivial
      private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
          GetField fields = in.readFields();
          domain = (String) fields.get(DOMAIN, null);
          id = (String) fields.get(ID, null);
      }
docs: Deserialize.
  
  @param in The stream from which this object is read.
  @throws IOException
  @throws ClassNotFoundException