我想向JPanel添加一个滚动条。有人知道怎么解决这个问题吗？

import javax.swing.*;
import java.awt.*;

public class ScrollablePanelExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Scrollable Panel Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 300);

        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(10, 1)); // 设置布局为网格布局，方便演示滚动条效果

        for (int i = 1; i <= 20; i++) {
            panel.add(new JLabel("Label " + i));
        }

        JScrollPane scrollPane = new JScrollPane(panel);
        frame.getContentPane().add(scrollPane);

        frame.setVisible(true);
    }
}