import java.awt.AWTException;
import java.awt.Image;
import java.awt.MenuItem;
import java.awt.PopupMenu;
import java.awt.SystemTray;
import java.awt.TrayIcon;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
import java.util.Calendar;
import java.util.Date;
import java.util.TimerTask;

import javax.imageio.ImageIO;
import javax.swing.JOptionPane;
import javax.swing.JSpinner;
import javax.swing.SpinnerDateModel;

public class Alarm {
    private TrayIcon icon;
    private Image clockImage;
    private Image alarmImage;

    private Date alarmTime;

    public Alarm() throws IOException, AWTException {
        SystemTray tray = SystemTray.getSystemTray();

        clockImage = ImageIO.read(new File("clock.png"));
        alarmImage = ImageIO.read(new File("alarm.png"));

        PopupMenu menu = new PopupMenu();
        MenuItem item = new MenuItem("時刻設定");
        item.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    configurateTime();
                }
            });
        menu.add(item);
        item = new MenuItem("終了");
        item.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent event) {
                    System.exit(0);
                }
            });
        menu.add(item);

        icon = new TrayIcon(clockImage, "アラーム", menu);
        tray.add(icon);
    }

    private void configurateTime() {
        if (alarmTime == null) {
            alarmTime = new Date();
        }

        JSpinner spinner = new JSpinner(new SpinnerDateModel(alarmTime, null, null, 
                                                             Calendar.SECOND));

        int value = JOptionPane.showConfirmDialog(null, spinner, "時刻設定", 
                                                  JOptionPane.OK_CANCEL_OPTION, 
                                                  JOptionPane.QUESTION_MESSAGE);
        if (value == JOptionPane.OK_OPTION) {
            alarmTime = (Date)spinner.getValue();
            TimerTask task = new TimerTask() {
                    public void run() {
                        icon.displayMessage("Alarm", "時間だよ!", TrayIcon.MessageType.INFO);
                        icon.setImage(alarmImage);
                        try {
                            Thread.sleep(20000L);
                        } catch (InterruptedException ex) {}
                        icon.setImage(clockImage);
                    }
                };
            java.util.Timer timer = new java.util.Timer();
            timer.schedule(task, alarmTime);
        }
    }

    public static void main(String[] args) {
        try {
            new Alarm();
        } catch (IOException ex) {
            ex.printStackTrace();
        } catch (AWTException ex) {
            ex.printStackTrace();
        }
    }
}