Hi friend,

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Arrays;


public class LoginPassword extends JPanel implements ActionListener {
private static String OK = "ok";
private static String HELP = "help";

private JFrame controllingFrame; //needed for dialogs
private JPasswordField passwordField;

public LoginPassword(JFrame f) {
//Use the default FlowLayout.
controllingFrame = f;

//Create everything.
passwordField = new JPasswordField(15);
passwordField.setActionCommand(OK);
passwordField.addActionListener(this);

JLabel label = new JLabel("Enter the password: ");
label.setLabelFor(passwordField);

JComponent buttonPane = createButtonPanel();

//Lay out everything.
JPanel textPane = new JPanel(new FlowLayout(FlowLayout.TRAILING));
textPane.add(label);
textPane.add(passwordField);
add(textPane);
add(buttonPane);
}

protected JComponent createButtonPanel() {
JPanel p = new JPanel(new GridLayout(0,1));
JButton okButton = new JButton("OK");
JButton helpButton = new JButton("Help");

okButton.setActionCommand(OK);
helpButton.setActionCommand(HELP);
okButton.addActionListener(this);
helpButton.addActionListener(this);

p.add(okButton);
p.add(helpButton);

return p;
}

public void actionPerformed(ActionEvent e) {
String cmd = e.getActionCommand();

if (OK.equals(cmd)) { //Process the password.
char[] input = passwordField.getPassword();
if (isPasswordCorrect(input)) {
JOptionPane.showMessageDialog(controllingFrame,
"Success! You typed the right password.");
} else {
JOptionPane.showMessageDialog(controllingFrame,"Invalid password. Try again.","Error Message",
JOptionPane.ERROR_MESSAGE);
}

//Zero out the possible password, for security.
Arrays.fill(input, '0');

passwordField.selectAll();
resetFocus();
} else { //The user has asked for help.
JOptionPane.showMessageDialog(controllingFrame,
"You can get the password by searching this example's\n"
+ "source code for the string \"correctPassword\".\n"
+ "Or look at the section How to Use Password Fields in\n"
+ "the components section of The Java Tutorial.");
}
}

private static boolean isPasswordCorrect(char[] input) {
boolean isCorrect = true;
char[] correctPassword = { 'b', 'u', 'g', 'a', 'b', 'o', 'o' };

if (input.length != correctPassword.length) {
isCorrect = false;
} else {
isCorrect = Arrays.equals (input, correctPassword);
}

//Zero out the password.
Arrays.fill(correctPassword,'0');

return isCorrect;
}

protected void resetFocus() {
passwordField.requestFocusInWindow();
}

private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("password example in java");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final LoginPassword newContentPane = new LoginPassword(frame);
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.addWindowListener(new WindowAdapter() {
public void windowActivated(WindowEvent e) {
newContentPane.resetFocus();
}
});
frame.setSize(500,200);
frame.setVisible(true);
}

public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
UIManager.put("swing.boldMetal", Boolean.FALSE);
createAndShowGUI();
}
});
}
}
-------------------------------

Read for more information.

http://www.roseindia.net/java/example/java/swing/

Thanks.

Amardeep