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

public class PasswordFieldExample implements  ActionListener{

    JPanel textPanel, panelForTextFields, completionPanel;
    JLabel titleLabel, usernameLabel, passwordLabel, userLabel, passLabel;
    JTextField usernameField;
    JPasswordField loginField;
    JButton loginButton;

    public JPanel createContentPane (){
 
        // We create a bottom JPanel to place everything on.
        JPanel totalGUI = new JPanel();
        totalGUI.setLayout(null);
         
        titleLabel = new JLabel("Login Screen");
        titleLabel.setLocation(0,0);
        titleLabel.setSize(290, 30);
        titleLabel.setHorizontalAlignment(0);
        totalGUI.add(titleLabel);

        // Creation of a Panel to contain the JLabels
        textPanel = new JPanel();
        textPanel.setLayout(null);
        textPanel.setLocation(10, 35);
        textPanel.setSize(70, 80);
        totalGUI.add(textPanel);

        // Username Label
        usernameLabel = new JLabel("Username");
        usernameLabel.setLocation(0, 0);
        usernameLabel.setSize(70, 40);
        usernameLabel.setHorizontalAlignment(4);
        textPanel.add(usernameLabel);

        // Login Label
        passwordLabel = new JLabel("Password");
        passwordLabel.setLocation(0, 40);
        passwordLabel.setSize(70, 40);
        passwordLabel.setHorizontalAlignment(4);
        textPanel.add(passwordLabel);

        // TextFields Panel Container
        panelForTextFields = new JPanel();
        panelForTextFields.setLayout(null);
        panelForTextFields.setLocation(110, 40);
        panelForTextFields.setSize(100, 70);
        totalGUI.add(panelForTextFields);

        // Username Textfield
        usernameField = new JTextField(8);
        usernameField.setLocation(0, 0);
        usernameField.setSize(100, 30);
        panelForTextFields.add(usernameField);

        // Login Textfield
        loginField = new JPasswordField(8);
        loginField.setEchoChar('&');
        loginField.setLocation(0, 40);
        loginField.setSize(100, 30);
        panelForTextFields.add(loginField);

        // Creation of a Panel to contain the completion JLabels
        completionPanel = new JPanel();
        completionPanel.setLayout(null);
        completionPanel.setLocation(240, 35);
        completionPanel.setSize(70, 80);
        totalGUI.add(completionPanel);

        // Username Label
        userLabel = new JLabel("Wrong");
        userLabel.setForeground(Color.red);
        userLabel.setLocation(0, 0);
        userLabel.setSize(70, 40);
        completionPanel.add(userLabel);

        // Login Label
        passLabel = new JLabel("Wrong");
        passLabel.setForeground(Color.red);
        passLabel.setLocation(0, 40);
        passLabel.setSize(70, 40);
        completionPanel.add(passLabel);

        // Button for Logging in
        loginButton = new JButton("Login");
        loginButton.setLocation(130, 120);
        loginButton.setSize(80, 30);
        loginButton.addActionListener(this);
        totalGUI.add(loginButton);
        
        totalGUI.setOpaque(true);
        return totalGUI;
    }

    // With this action performed, we simply check to see if the username and 
    // password match "Bob" as the username and "Robert" as the password.
    // If they do, we set the labels ajacent to them to "Correct!" and color
    // them green.
    // At the end, we check if both labels are green. If they are, we set the
    // screen to be 'Logging In'.

    public void actionPerformed(ActionEvent e) {

        if(e.getSource() == loginButton)
        {
            if(usernameField.getText().trim().compareTo("Bob") == 0)
            {
                userLabel.setForeground(Color.green);
                userLabel.setText("Correct!");
            }
            else
            {
                userLabel.setForeground(Color.red);
                userLabel.setText("Wrong!");
            }

            // Here, because we use a password field, we use the getPassword 
            // command. This is more secure. 
            // Once we are finished with the char array with the correct answer
            // we change it back to blank.
            // You may ask why we do this when the char array we compare it to 
            // is in clear text one line above.
            // Obviously we'd store this in an encrypted database. (or something
            // along those lines!)

            char[] answer = {'R', 'o', 'b', 'e', 'r', 't'};
            char[] input = loginField.getPassword();

            if(Arrays.equals(input, answer))
            {
                passLabel.setForeground(Color.green);
                passLabel.setText("Correct!");
                for(int i = 0; i < input.length; i++)
                {
                    input[i] = ' ';
                }
            }
            else
            {
                passLabel.setForeground(Color.red);
                passLabel.setText("Wrong!");
            }

            if((userLabel.getForeground() == Color.green) 
            && (passLabel.getForeground() == Color.green))
            {
                titleLabel.setText("Logging in....");
                loginButton.setEnabled(false);
            }
        }
    }


    private static void createAndShowGUI() {

        JFrame.setDefaultLookAndFeelDecorated(true);
        JFrame frame = new JFrame("[=] JPassword of Secrets! [=]");

        PasswordFieldExample demo = new PasswordFieldExample();
        frame.setContentPane(demo.createContentPane());
        
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(310, 200);
        frame.setVisible(true);
    }


    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

// *************************************************************
// Name : PasswordFieldExample.java
// Author : Stuart Davidson
// Date : 21/12/2006
// Description : Shows how a PasswordField is different to a TextField.
// *************************************************************