/*
   Chapter 9:     Hands On
   Programmer:    Brad Shedd
   Date:          September 08, 2006
   Program Name:  PasswordDemo.java
*/

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

public class PasswordDemo
{
    public static void main(String[] argv)
    {
      int width = 400;
      int height = 130;
        final demoFrame f = new demoFrame("PasswordDemo");

        f.pack();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      f.setSize(width, height);
      f.centerOnScreen(width, height);
      f.setVisible(true);
    }
}

class demoFrame extends JFrame implements ActionListener
{
    Password password = null;
    String pswd, newPswd;

    JPasswordField pswdField;
    JPasswordField newPswdField;
    JButton jbtAddPswd, jbtChangePswd, jbtUsePswd;

    public demoFrame(String title)
    {
        super(title); // call super (JFrame) constructor

        JLabel label1 = new JLabel("Current Password:");
        pswdField = new JPasswordField(20);
        pswdField.setEchoChar('*');

        JLabel label2 = new JLabel("New Password:", JLabel.RIGHT);
        newPswdField = new JPasswordField(20);
        newPswdField.setEchoChar('*');

        jbtAddPswd = new JButton("Add password");
        jbtChangePswd = new JButton("Change password");
        jbtUsePswd = new JButton("Use password");

        jbtAddPswd.addActionListener(this);
        jbtChangePswd.addActionListener(this);
        jbtUsePswd.addActionListener(this);

        JPanel pswdPanel= new JPanel(new BorderLayout(10,10));
        pswdPanel.add(label1,BorderLayout.WEST);
        pswdPanel.add(pswdField,BorderLayout.EAST);

        JPanel newPswdPanel= new JPanel(new BorderLayout(19,19));
        newPswdPanel.add(label2,BorderLayout.WEST);
        newPswdPanel.add(newPswdField,BorderLayout.EAST);

        JPanel buttonPanel= new JPanel(new FlowLayout());
        buttonPanel.add(jbtAddPswd);
        buttonPanel.add(jbtChangePswd);
        buttonPanel.add(jbtUsePswd);

        JPanel contentPanel= new JPanel(new FlowLayout());
        contentPanel.add(pswdPanel);
        contentPanel.add(newPswdPanel);
        contentPanel.add(buttonPanel);
        setContentPane(contentPanel);

      // Enable Enter key for each JButton so user can tab to button
      // and press the Enter key, rather than click button with mouse
      InputMap map;
      map = jbtAddPswd.getInputMap();
      if (map != null){
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,false), "pressed");
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,true), "released");
      }
      map = jbtChangePswd.getInputMap();
      if (map != null){
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,false), "pressed");
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,true), "released");
      }
      map = jbtUsePswd.getInputMap();
      if (map != null){
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,false), "pressed");
         map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER,0,true), "released");
      }
    }

   public void centerOnScreen(int width, int height)
  {
     int top, left, x, y;

     // Get the screen dimension
     Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();

     // Determine the location for the top left corner of the frame
     x = (screenSize.width - width)/2;
     y = (screenSize.height - height)/2;
     top = (x < 0) ? 0 : x;
     left = (y < 0) ? 0 : y;

     // Set the frame to the specified location
     this.setLocation(top, left);
   }

    public void actionPerformed(ActionEvent e)
    {
      String msg;
      String title;
      int optionType;
     try
        {
         if(e.getSource() == jbtUsePswd)     // user clicked Use password
            {
             pswd = new String(pswdField.getPassword());   // get current pswd entered
            password.validate(pswd);

                  if(password.isExpiring())
                  {
                     msg = "Password use successful; " + password.getRemainingUses()+" use(s) remaining.";
                     title = "Success";
                   optionType = JOptionPane.WARNING_MESSAGE;
            }
                  else
            {
                     msg = "Password use successful";
                     title = "Success";
                   optionType = JOptionPane.INFORMATION_MESSAGE;
            }
            }
            else if(e.getSource() == jbtChangePswd)      // user clicked Change password
            {
            newPswd = new String(newPswdField.getPassword());
              password.set(newPswd);

                  msg = "Password changed.";
                  title = "Success";
                optionType = JOptionPane.INFORMATION_MESSAGE;
            }
            else if(e.getSource() == jbtAddPswd)      // user clicked Add password
            {
             newPswd = new String(newPswdField.getPassword());
                password = new Password(newPswd,5); // auto expires after 5 additional uses

            if(password.getAutoExpires())
                     msg = "Success! Password added with "+password.getRemainingUses()+" remaining uses.";
                  else
                msg = "Success! Password added - not set to expire.";

                  title = "Success";
                optionType = JOptionPane.INFORMATION_MESSAGE;
           }
            else  // can never happen
            {
                  msg = "Please choose a valid action.";
                  title = "Invalid Action";
                optionType = JOptionPane.WARNING_MESSAGE;
         }

            JOptionPane.showMessageDialog(this, msg, title, optionType);
         pswdField.setText("");
         newPswdField.setText("");
         pswdField.requestFocus();

        }// end of try
        catch (NullPointerException ex)
        {
           JOptionPane.showMessageDialog(this,"No Password yet created",
                                               "Invalid password. Try again.",
                                        JOptionPane.ERROR_MESSAGE);
        }
        catch (Exception ex)
        {
            JOptionPane.showMessageDialog(this, ex.getMessage(),
                                                "Invalid password. Try again.",
                                                JOptionPane.ERROR_MESSAGE);
        }
    }
}

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