code: private void readObject(java.io.ObjectInputStream s)
          throws java.io.IOException, ClassNotFoundException {
          java.io.ObjectInputStream.GetField fields = s.readFields();
          char[] value = (char[])fields.get("value", null);
          int count = fields.get("count", 0);
          append(value, 0, count);
      }
docs: readObject is called to restore the state of the StringBuffer from
  a stream.