在标题栏上显示自己的图标

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

public class Test extends JPanel {

    private static void createAndShowGUI() {
        JFrame frame = new JFrame("Change Icon");
        
        Image icon = new ImageIcon("image.png").getImage();
        frame.setIconImage(icon); // 关键之处在这里
        
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 500);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                Test.createAndShowGUI();
            }
        });
    }
}