来自URL的Java JFrame setImageIcon图像不起作用

import javax.swing.*;
import java.awt.*;
import java.net.URL;
import java.io.IOException;

public class MainFrame extends JFrame {
    public MainFrame() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setTitle("My JFrame");
        setSize(400, 300);

        try {
            // 从URL加载图像
            URL imageUrl = new URL("https://example.com/image.jpg");
            ImageIcon icon = new ImageIcon(imageUrl);

            // 设置JFrame的图标
            setIconImage(icon.getImage());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            MainFrame frame = new MainFrame();
            frame.setVisible(true);
        });
    }
}