test/jdk/java/awt/Graphics2D/ImageRendering/ImageRendering.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 */

/*
 * @test
 * @bug 4203598
 * @summary This test verifies that an image with transparent background can be displayed
 *          correctly with the red background color given.
 *           The correct display should be the sleeping Duke on a red background.
 *
 */

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;

public class ImageRendering {

    public static void main(String[] args) throws Exception {

        String imgName = "snooze.gif";
        File file = new File(System.getProperty("test.src", "."), imgName);
        BufferedImage image = ImageIO.read(file);
        int w = image.getWidth();
        int h = image.getHeight();
        BufferedImage dest = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2d = dest.createGraphics();
        g2d.drawImage(image, 0, 0, Color.red, null);
        int redPixel = Color.red.getRGB();
        for (int y = 0; y < h; y++) {
            for (int x = 0; x < w; x++) {
                int srcPixel = image.getRGB(x, y);
                if ((srcPixel & 0x0ff000000) == 0) {
                    int destPix = dest.getRGB(x, y);
                    if (destPix != redPixel) {
                        throw new RuntimeException("Not red at x=" + x +
                               " y=" + y +
                               "pix = " + Integer.toHexString(destPix));
                    }
                }
            }
       }
    }
}