动态时间显示到窗口

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class ClockApp extends JFrame {

    private JLabel timeLabel;

    public ClockApp() {
        setTitle("实时时钟");
        setSize(200, 100);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        timeLabel = new JLabel();

        // 初始显示时间
        updateTime();

        // 创建定时器，每秒刷新时间
        Timer timer = new Timer(1000, new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                updateTime();
            }
        });
        timer.start();

        add(timeLabel);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    // 更新时间标签
    private void updateTime() {
        LocalDateTime now = LocalDateTime.now();
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss");
        String formattedTime = now.format(formatter);
        timeLabel.setText("时间：" + formattedTime);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            new ClockApp();
        });
    }
}