1-) Java - password yani şifre dialogu oluşturma

public String Sifre = "sifrem";

public void MyExitDialog() {

        JPanel panel = new JPanel();

        JLabel label = new JLabel("Şifre : ");

        JPasswordField pass = new JPasswordField(10);

        panel.add(label);

        panel.add(pass);

        String[] options = new String[]{"OK", "Cancel"};

        int option = JOptionPane.showOptionDialog(null, panel, "RMOS Lisans Şifresini Giriniz!",

                JOptionPane.NO_OPTION, JOptionPane.PLAIN_MESSAGE,

                null, options, options[0]);

        if (option == 0) // pressing OK button

        {

            char[] password = pass.getPassword();

            String s = new String(password);

            if (s.toUpperCase().equals(Sifre.toUpperCase())) {

                // JOptionPane.showMessageDialog(null, "Girildi");

            } else {

                JOptionPane.showMessageDialog(null, "Şifre Yanlış!");

                MyExitDialog();

            }

             return;

        }

        System.exit(0);

    }