问通过图像透明性Java查看JButton

EN

grid.add(new JPanel(){{
    setLayout(new BorderLayout());
    add(new JButton() {{
        setLayout(new BorderLayout());
        setBorder(new EmptyBorder(0, 0, 0, 0));
        add(new JImageComponent(new ImageIcon(this.getClass().getResource("/Center.png"))));
    }});
}});

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MediaTracker;
import java.awt.image.BufferedImage;

import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JPanel;

public class JImageComponent extends JPanel {

    Image image;

    public JImageComponent(ImageIcon img) {
        BufferedImage imgs;
        setBorder(BorderFactory.createLineBorder(Color.black));
        setPreferredSize(new Dimension(1000, 1000));
        image = img.getImage();
        repaint();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        //Container parent = getParent();
        Image scaledImage = image.getScaledInstance(getWidth(), getHeight(), Image.SCALE_DEFAULT);
        MediaTracker tracker = new MediaTracker(new java.awt.Container());
        tracker.addImage(scaledImage, 0);
        try {
            tracker.waitForAll();
        } catch (InterruptedException ex) {
            throw new RuntimeException("Image loading interrupted", ex);
        }
        g.drawImage(scaledImage, 0, 0, this);
    }
}