我有一个swing应用程序，我想在jbutton上显示一个图标。我有一些问题，windows缩放图标，使它非常难看。我能够通过使用图标 Package 器类解决这个问题，如这里所述。
使用 Package 器类解决了我遇到的缩放问题，但也带来了一个新问题：当我将鼠标移到按钮上时，图标只显示一次，如下所示：

下面是一个简单的例子：

import javax.swing.*;
import java.awt.*;
import java.net.MalformedURLException;
import java.net.URL;

public class Ui {
    private static JFrame frame;
    private static JButton button1;
    private static JButton button2;
    private static JMenuBar jMenuBar;

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            try {
                createGui();
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }
        });
    }

    private static void createGui() throws MalformedURLException {
        frame = new JFrame("Test");

        button1 = new JButton();
        button2 = new JButton();
        jMenuBar = new JMenuBar();

        Icon icon = new NoScalingIcon(new ImageIcon(new URL("https://i.stack.imgur.com/wgKeq.png")));
        button1.setIcon(icon);
        button2.setIcon(icon);

        jMenuBar.add(button1);
        jMenuBar.add(button2);
        frame.setJMenuBar(jMenuBar);
        frame.pack();
        frame.setVisible(true);
        frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
    }
}

图标 Package 类：

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

public class NoScalingIcon implements Icon {
    private Icon icon;

    public NoScalingIcon(Icon icon) {
        this.icon = icon;
    }

    public int getIconWidth() {
        return icon.getIconWidth();
    }

    public int getIconHeight() {
        return icon.getIconHeight();
    }

    public void paintIcon(Component c, Graphics g, int x, int y) {
        Graphics2D g2d = (Graphics2D) g.create();

        AffineTransform at = g2d.getTransform();
        int scaleX = (int) (x * at.getScaleX());
        int scaleY = (int) (y * at.getScaleY());

        int offsetX = (int) (icon.getIconWidth() * (at.getScaleX() - 1) / 2);
        int offsetY = (int) (icon.getIconHeight() * (at.getScaleY() - 1) / 2);

        g2d.setTransform(new AffineTransform());

        icon.paintIcon(c, g2d, scaleX + offsetX, scaleY + offsetY);

        g2d.dispose();
    }
}

这个问题的原因是什么？