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import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
public class Password extends JFrame implements ActionListener { //TestJPF
JPasswordField jpf;
String pwd = "cae4";
int count;
JTextField jtf;
public Password () {
count = 0;
jtf = new JTextField(15);
jtf.setEditable(false);
// A JPasswordField object is created. The echo character is
// set to '$' and the JPasswordField object is registered with
// an ActionListener.
jpf = new JPasswordField(20);
jpf.setEchoChar('$');
jpf.addActionListener(this);
JPanel p = new JPanel();
p.setLayout(new FlowLayout(FlowLayout.CENTER, 20, 20));
p.add(jpf);
getContentPane().add(p, BorderLayout.CENTER);
getContentPane().add(jtf, BorderLayout.SOUTH);
// The WindowListener is used to terminate the program when the window
// is closed. Under Java 2 version 1.3, the addWindowListener() syntax
// can be replaced by
//
// setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addWindowListener(new WinClosing());
setBounds(100, 100, 300, 150);
setVisible(true);
}
// When the JPasswordField has focus and the enter key is pressed,
// an ActionEvent is generated and the actionPerformed() method is
// called. The entered text is compared against the password.
// After 3 unsuccessful tries, the program terminates.
public void actionPerformed(ActionEvent ae) {
String enteredPwd = new String(jpf.getPassword());
if (pwd.equals(enteredPwd)) {
jtf.setText("Password accepted");
} else {
if (count > 2) {
System.exit(0);
}
jtf.setText("Wrong Password");
++count;
}
}
public static void main(String args[]) {
Password tjp = new Password ();
}
}
// The WinClosing class terminates the program when the window is closed
class WinClosing extends WindowAdapter {
public void windowClosing(WindowEvent we) {
System.exit(0);
}
} |