What is the correct action to take when closing a window in Java / swing?

I wrote this test code in my customuipanel class:

public static void main(String[] args) {
    final JDialog dialog = CustomUIPanel.createDialog(null,CustomUIPanel.selectFile());
    dialog.addWindowListener(new WindowAdapter() {
        @Override public void windowClosing(WindowEvent e) {
            System.exit(0);
        }
    });
}

If customuipanel Main () is the entry point of the program. It works normally, but it makes me wonder what: if another class is called customuipanel What about main()? So I'm right about system The call to exit (0) is incorrect

If there is no top-level window, is there any way to tell the swing event sending thread to exit automatically?

If not, what does jdialog / JFrame do when it closes if the program exits with all top-level windows closed?

Solution

You can use jdialog's setdefaultcloseoperation() method to specify dispose_ ON_ CLOSE：

setDefaultCloSEOperation(JDialog.DISPOSE_ON_CLOSE);

See 12.8 program exit

Appendix: combined with @ camickr's help answer, this example exits when the window is closed or the close button is pressed

import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.WindowEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;

/** @see https://stackoverflow.com/questions/5540354 */
public class DialogClose extends JDialog {

    public DialogClose() {
        this.setLayout(new GridLayout(0,1));
        this.add(new JLabel("Dialog close test.",JLabel.CENTER));
        this.add(new JButton(new AbstractAction("Close") {

            @Override
            public void actionPerformed(ActionEvent e) {
                DialogClose.this.setVisible(false);
                DialogClose.this.dispatchEvent(new WindowEvent(
                    DialogClose.this,WindowEvent.WINDOW_CLOSING));
            }
        }));
    }

    private void display() {
        this.setDefaultCloSEOperation(JDialog.DISPOSE_ON_CLOSE);
        this.pack();
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokelater(new Runnable() {

            @Override
            public void run() {
                new DialogClose().display();
            }
        });
    }
}