Making a program "sit and wait"

Question

I've written a program that drops an icon in the system tray and just waits around for the user to do something with it. When I first wrote the program, it would add the icon to the tray, then immediately exit since there weren't any active threads. I remedied the situation by starting a thread that consists solely of:
while (true) {
     Thread.sleep(9999999);
}This does what I want it to, but it seems like there should be a better way of preventing the JVM from exiting automatically. Any ideas?

Answer 1

I just have an ActionListener strapped to the icon...
the user clicks it, and an ActionEvent is fired off.
No additional thread needed as far as I know.Then you have (I suppose) a Swing framework app, which creates threads behind the scenes. Not a Swing developer myself, but normally one creates normal Swing apps with a visible form, and that doesn't terminate until you close the form. If you're creating a "Windows tray icon" thingy, (which of course would only work on Windows), sounds like for one thing you're using the wrong tool for the job (java is for platform independence, not for Windows-specific apps). But if you want to continue down this road, you should research how Swing creates its threads, and maybe you can "tell" it to make the thread that it is creating a non-daemon thread (or if it creates non-daemon threads, tell it to create a daemon thread instead - I don't remember which type does what).