URL url = new URL("http://www.foo.org?bar=baz");
HttpURLConnection conn =
(HttpURLConnection)url.openConnection();
conn.setRequestMethod("HEAD");
conn.setUseCaches(false);
if (conn.getResponseCode() != HttpURLConnection.HTTP_OK) {
System.out.println(conn.getResponseMessage());
}
else {
// Verarbeitung des Ergebnisses
}