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import javax.swing.*;
import java.awt.*;
 
public class PanelDisplayExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Panel Display Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        // 创建左屏
        JPanel leftPanel = new JPanel() {
            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                // 在这里绘制你想显示的内容
                g.drawString("Left Screen Content", 20, 20);
            }
        };
 
        // 创建右屏
        JPanel rightPanel = new JPanel() {
            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                // 绘制左屏的内容到右屏
                leftPanel.paint(g);
            }
        };
 
        // 将左屏和右屏添加到窗口中
        frame.add(leftPanel, BorderLayout.WEST);
        frame.add(rightPanel, BorderLayout.EAST);
 
        // 设置窗口的大小并显示
        frame.setSize(400, 300);
        frame.setVisible(true);
    }
}