public class Temp
{
public static void main(String[] args)
{
final JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
int select = JOptionPane.showConfirmDialog(frame, "真的要退出吗?");
if (select == JOptionPane.YES_OPTION)
frame.dispose();
}