First of all, create a string array with the elements of a browser exe path and the file you desire to open in your browser. Next, create an instance of Runtime class and invoke exec methods to execute the browser exe. This returns a Process object.
Here is sample code:
public class opening{ public static void main(String args[]) { try { Runtime rt=Runtime.getRuntime(); Stringstr[]={"c:\progra~1\intern~1\iexplore.exe","c:/basha/index.html"}; Process p=rt.exec(str); } catch(Exception e) {System.out.println(e);} }}