protected int createHashCode(){
  int result=uri.hashCode() ^ prefix.hashCode();
  if (result == 0) {
    result=0xbabe;
  }
  return result;
}

protected int createHashCode ( ) { int result = uri . hashCode ( ) ^ prefix . hashCode ( ) ; if ( result == 0 ) { result = 0xbabe ; } return result ; }
factory method to create the hashcode allowing derived classes to change the behaviour
