s.writeObject(language); s.writeObject(country); s.writeObject(variant);  s.writeInt(-1);
ObjectOutputStream.PutField fields = s.putFields(); fields.put("hashcode", -1); s.defaultWriteObject();
  private void writeObject(ObjectOutputStream s)    throws IOException  {    s.writeObject(language);    s.writeObject(country);    s.writeObject(variant);    // Hashcode field is always written as -1.    s.writeInt(-1);  }