How do I invoke extra operations when the user closes a JFrame
window? I have to stop existing threads.
As I understand it, setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
causes the frame to be closed and its thread to be stopped. Should threads be closed after JFrame.EXIT_ON_CLOSE
?
Client:
static boolean TERMINATE = false;
public static void main(String[] args) {
// some threads created
while(true) {
if(TERMINATE){
// do before frame closed
break;
}
}
}
private static JPanel startGUI(){
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel gui = new JPanel();
f.add( gui);
f.setSize(500,500);
f.setVisible(true);
return gui;
}
I need to close sockets the thread's working with. What is the best practice to do that?
Using JFrame.EXIT_ON_CLOSE
actually terminates the JVM (System.exit
). All running threads will automatically be stopped.
If you want to perform some action when a JFrame
is about to close, use a WindowListener
.
JFrame frame = ...
frame.addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
// close sockets, etc
}
});