Why does my application still run after closing main window?

Question

If I make a JFrame like this

public static void main(String[] args) {

     new JFrame().setVisible(true);
}

then after closing the window the appication doesn't stop (I need to kill it).

What is the proper way of showing application's main windows ?

I'd also like to know a reason of a proposed solution.

Thanks in advance.

Answer 1

You should call the setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); in your JFrame.

Example code:

public static void main(String[] args) {
    Runnable guiCreator = new Runnable() {
        public void run() {
            JFrame fenster = new JFrame("Hallo Welt mit Swing");
            fenster.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            fenster.setVisible(true);
        }
    };
    SwingUtilities.invokeLater(guiCreator);
}

Answer 2

There's a difference between the application window and the application itself... The window runs in its own thread, and finishing main() will not end the application if other threads are still active. When closing the window you should also make sure to close the application, possibly by calling System.exit(0);

Yuval =8-)