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

In response to your question, the port solution will keep more resources from the machine:
- You will keep a port locked: ports are limited and you may find problems with firewalls or other programs listening on the same port.
- You'll need an active thread.

The file solution will use less resources from the machine, to avoid locking the file forever you need to add a thread, to delete the file, in the addShutdownHook method from Runtime.