Java 定时器类 Timer 使用方法，定时器timer,import java.

Java 定时器类 Timer 使用方法，定时器timer,import java.

import java.awt.*;import java.awt.event.*;import java.text.SimpleDateFormat;import java.util.*;import java.util.Timer;import javax.swing.*;public class SimpleTimer extends JWindow {    public static void main(String[] args) {        SimpleTimer simpleTimer = new SimpleTimer();        simpleTimer.pack();        simpleTimer.setAlwaysOnTop(true);        simpleTimer.setVisible(true);    }    private Long startTimeMillis;    private JLabel label;    private SimpleDateFormat dateFormat;    private Timer timer;    public SimpleTimer() {        initDateFormat();        initConponents();        resetTime();        updateLabelText();        startTimer();    }    private void initDateFormat() {        dateFormat = new SimpleDateFormat("HH:mm:ss");        dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));    }    private void initConponents() {        label = new JLabel();        label.setFont(new Font(label.getFont().getName(), Font.BOLD, 14));        label.setOpaque(true);        label.setBackground(Color.black);        label.setForeground(Color.white);        label.setBorder(BorderFactory.createEmptyBorder(0, 2, 0, 2));        getContentPane().add(label);        final JPopupMenu popup = new JPopupMenu();        JMenuItem menuItem1 = new JMenuItem("Reset");        menuItem1.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                resetTime();            }        });        popup.add(menuItem1);        JMenuItem menuItem2 = new JMenuItem("Exit");        menuItem2.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                System.exit(0);            }        });        popup.add(menuItem2);        label.setComponentPopupMenu(popup);        label.addMouseListener(new MouseAdapter() {            @Override            public void mouseClicked(MouseEvent e) {                if (e.getButton() == MouseEvent.BUTTON2                        && e.getClickCount() == 1) {                    popup.setVisible(true);                }            }        });    }    private void resetTime() {        startTimeMillis = Calendar.getInstance().getTimeInMillis();    }    /**     * ラベル更新     */    private void updateLabelText() {        SwingUtilities.invokeLater(new Runnable() {            public void run() {                long elapsedTime = Calendar.getInstance().getTimeInMillis()                        - startTimeMillis;                Date date = new Date(elapsedTime);                label.setText(dateFormat.format(date));            }        });    }    /**     * タイマー開始     */    private void startTimer() {        timer = new Timer();        timer.schedule(new TimerTask() {            @Override            public void run() {                updateLabelText();            }        }, 0, 1000);    }}