Remplacer des espaces avec% 20 en Java

String url = "http://maps.googleapis.com/maps/api/distancematrix/xml?origins="+origin+"&destinations="+destination+"&mode=driving&sensor=false&language=en-EN&units=imperial";
url = url.replaceAll(" ", "%20");

De sortie :

http://maps.googleapis.com/maps/api/distancematrix/xml?origins=150%20Sutter%20St%20San%20Francisco,%20CA,%20United%20States&destinations=1%20Palmer%20Sq%20E
Princeton,%20NJ%2008542&mode=driving&sensor=false&language=en-EN&units=imperial

Mais j'obtiens un message d'erreur indiquant :

java.net.MalformedURLException: Illegal character in URL

Peut quelqu'un m'aider ..

source d'informationauteur user3742241