在JFrame有背景时添加带时间和日期的状态栏

JFrame frame = new JFrame();
frame.setLayout(new BorderLayout());

JPanel statusBar = new JPanel();
statusBar.setLayout(new FlowLayout(FlowLayout.LEFT));

SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
JLabel timeLabel = new JLabel(dateFormat.format(new Date()));
statusBar.add(timeLabel);

Timer timer = new Timer(1000, e -> {
    timeLabel.setText(dateFormat.format(new Date()));
});
timer.start();

frame.add(statusBar, BorderLayout.SOUTH);

import javax.swing.*;
import java.awt.*;
import java.text.SimpleDateFormat;
import java.util.Date;

public class JFrameWithStatusBar {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setLayout(new BorderLayout());

        JPanel statusBar = new JPanel();
        statusBar.setLayout(new FlowLayout(FlowLayout.LEFT));

        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        JLabel timeLabel = new JLabel(dateFormat.format(new Date()));
        statusBar.add(timeLabel);

        Timer timer = new Timer(1000, e -> {
            timeLabel.setText(dateFormat.format(new Date()));
        });
        timer.start();

        frame.add(statusBar, BorderLayout.SOUTH);

        frame.setSize(400, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}