Restrict multiple instances of an application in java

Question

I want to prevent multiple instances of application being launched in java. I know 2 methods for this:

1. locking file
2. locking socket

But

Answer 1

If you deploy with Java WebStart the SingleInstanceService does this.

See http://download.oracle.com/javase/6/docs/technotes/guides/javaws/developersguide/faq.html#218