JFrame On Close Operation

Question

I was wondering if there is a way, by clicking on the "X", to let the program perform some code before closing the JFrame. The setDefaultCloseOperation() method takes only an integer.

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

Answer 1

this.addWindowListener(new WindowAdapter(){
                public void windowClosing(WindowEvent e){
                    int i=JOptionPane.showConfirmDialog(null, "Seguro que quiere salir?");
                    if(i==0)
                        System.exit(0);//cierra aplicacion
                }
            });