public URLConnection openConnection(Proxy proxy) throws IOException {
  if (proxy == null) {
    throw new IllegalArgumentException("proxy == null");
  }
  return streamHandler.openConnection(this,proxy);
}

public URLConnection openConnection ( Proxy proxy ) throws IOException { if ( proxy == null ) { throw new IllegalArgumentException ( "proxy == null" ) ; } return streamHandler . openConnection ( this , proxy ) ; }
returns a new connection to the resource referred to by this url .
