check for single instance java program [duplicate]

Question

I have a program in Java (with a swing gui), and I would like only 1 instance ever to exist. If it attempted to open another instance of the program I would like the current instance to be brought to the foreground.

How do I do this?

Thanks in advance.

Answer 1

Launch the application using Java Web Start and implement the SingleInstanceService of the JNLP API. Here is a demo. of the SingleInstanceService.

If it attempted to open another instance of the program I would like the current instance to be brought to the foreground.

Hook that up in the newActivation(String[]) method of the SingleInstanceListener. It will be passed any arguments that were provided for the new launch. The existing instance gets to decide what to do with the new args (e.g. change file, add new tab, ignore..)