GUI实现显示当前时间

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package com.westos.javase.lesson08;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.File;

import javax.swing.JLabel;
import javax.swing.JWindow;
import javax.swing.Timer;

public class MyClock extends JWindow implements ActionListener {
JLabel lc = new JLabel();
Timer timer = new Timer(1000, this); // 定时器

public MyClock() {    lc.setHorizontalAlignment(JLabel.CENTER);    lc.setVerticalAlignment(JLabel.CENTER);    lc.setText(String.format("%tT", System.currentTimeMillis()));    // 液晶字体    Font f = null;    try {        f = Font.createFont(Font.TRUETYPE_FONT, new File("FX-LED002.TTF"));        f = f.deriveFont(74f);    } catch (Exception e) {        e.printStackTrace();        f = new Font("黑体", Font.BOLD, 60);    }    lc.setFont(f);    lc.setOpaque(true);    lc.setForeground(Color.RED);    lc.setBackground(Color.BLACK);    add(lc);    setSize(300, 150);//  setDefaultCloseOperation(EXIT_ON_CLOSE);    // 启动定时器    timer.start();    //双击关闭    this.addMouseListener(new MouseAdapter() {        @Override        public void mouseClicked(MouseEvent e) {          //System.out.println(e.getButton());            if(e.getButton() == MouseEvent.BUTTON1 && e.getClickCount() == 2) { //左键双击                dispose();                System.exit(0);            }        }    });}public static void main(String[] args) {    MyClock clock = new MyClock();    // 窗口居中    Dimension di = Toolkit.getDefaultToolkit().getScreenSize(); // 获取屏幕大小    System.out.println(di.width + "*" + di.height);    int x = (di.width - clock.getWidth()) / 2;    int y = (di.height - clock.getHeight()) / 2;    clock.setLocation(x, y);    clock.setVisible(true);}@Overridepublic void actionPerformed(ActionEvent e) {    // System.out.println("aaaaaaaaaa");    lc.setText(String.format("%tT", System.currentTimeMillis()));}

}

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