With this code you can open a web browser and navigate to a given URL.

You can place this in the Main method or in a JButton etc..

String[] cmd = new String[4];
cmd[0] = "cmd.exe";
cmd[1] = "/C";
cmd[2] = "start";
cmd[3] = "http://www.javaprogrammingforums.com";
Process p = Runtime.getRuntime().exec(cmd);