Question

I have made an application and i need to save some options before exit.(something like window dimension, …, that will be written in a file.)

The main frame has set this:

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

How can I save options that interests me?(before exiting of course)

Thanks!

Answer 1

If you just want to do something when the application is shutting down, you can hook the shutdown using this code:

    Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {

        public void run() {
            // Do what you want when the application is stopping
        }
    }));

However, this will not allow you to not close your window. If you need to check something before really exiting, you can override the windowClosing event:

addWindowListener(new WindowAdapter() {
    public void windowClosing(WindowEvent e) {
        // Do what you want when the window is closing.
    }
});

Note that the first solution – using the shutdown hook – has the advantage that it is not related to a window event, and will be executed even if the application is stopped by another event (except, of course, if the Java process is killed brutally).