Swing JLayerで任意のコンポーネントを階調反転させる

InvertColorLayerUI.java

import javax.swing.*;
import javax.swing.plaf.LayerUI;
import java.awt.*;
import java.awt.image.*;

public class InvertColorLayerUI extends LayerUI<JComponent> {
	private BufferedImage bufferedImage;
	@Override
	public void paint(Graphics g, JComponent c) {
		int w = c.getWidth();
		int h = c.getHeight();
		if (w == 0 || h == 0) return;

		if (bufferedImage == null
				|| bufferedImage.getWidth() != w
				|| bufferedImage.getHeight() != h) {
			bufferedImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
		}

		Graphics2D g2 = bufferedImage.createGraphics();
		g2.setClip(g.getClip());
		super.paint(g2, c);
		g2.dispose();

		FilteredImageSource filtered = new FilteredImageSource(
				bufferedImage.getSource(),
				new InvertColorFilter()
		);
		Image image = c.createImage(filtered);
		g.drawImage(image, 0, 0, c);
	}

	class InvertColorFilter extends RGBImageFilter {
		@Override
		public int filterRGB(int x, int y, int argb) {
			int alpha = argb & 0xFF000000;
			int rgb = ~(argb & 0xFFFFFF);
			return alpha | rgb;
		}
	}
}

class InvertTestWindow {
	public static void main(String[] args) throws Exception {
		JFrame frame = new JFrame();
		frame.setSize(200, 200);

		JPanel panel = new JPanel();
		LayerUI<JComponent> layerUI = new InvertColorLayerUI();
		JLayer<JComponent> layer = new JLayer<JComponent>(panel, layerUI);
		frame.add(layer);

		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	}
}