DataExchangeFrame.java

package dataExchange;

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

/**
 * A frame with a menu whose File->Connect action shows a password dialog.
 */
public class DataExchangeFrame extends JFrame {
    public static final int TEXT_ROWS = 20;
    public static final int TEXT_COLUMNS = 40;
    private PasswordChooser dialog = null;
    private JTextArea textArea;

    public DataExchangeFrame() {
        // construct a File menu

        JMenuBar menuBar = new JMenuBar();
        setJMenuBar(menuBar);
        JMenu fileMenu = new JMenu("File");
        menuBar.add(fileMenu);

        // add Connect and Exit menu items

        JMenuItem connectItem = new JMenuItem("Connect");
        connectItem.addActionListener(new ConnectAction());
        fileMenu.add(connectItem);

        // The Exit item exits the program

        JMenuItem exitItem = new JMenuItem("Exit");
        exitItem.addActionListener(e -> System.exit(0));
        fileMenu.add(exitItem);

        textArea = new JTextArea(TEXT_ROWS, TEXT_COLUMNS);
        add(new JScrollPane(textArea), BorderLayout.CENTER);
        pack();
    }

    /**
     * The Connect action pops up the password dialog.
     */
    private class ConnectAction implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            // if first time, construct dialog

            if (dialog == null) dialog = new PasswordChooser();

            // set default values
            dialog.setUser(new User("your name", null));

            // pop up dialog
            if (dialog.showDialog(DataExchangeFrame.this, "Connect")) {
                // if accepted, retrieve user input
                User user = dialog.getUser();
                textArea.append("user name = " + user.getName() + ", password = " +
                        (new String(user.getPassword())) + "\n");
            }
        }
    }
}