1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 /**
  24  * @test
  25  * @bug 8080287 8136354
  26  * @run main RescaleAlphaTest
  27  * @summary RescaleOp with scaleFactor/alpha should copy alpha to destination
  28  * channel
  29  */
  30 import java.awt.Graphics2D;
  31 import java.awt.image.BufferedImage;
  32 import java.awt.image.RescaleOp;
  33 import java.awt.Color;
  34 import java.awt.Frame;
  35 import java.io.IOException;
  36 
  37 public class RescaleAlphaTest {
  38 
  39     BufferedImage bimg = null, bimg1;
  40     int w = 10, h = 10;
  41     float scaleFactor = 0.5f;
  42     float offset = 0.0f;
  43 
  44     public static void main(String[] args) throws Exception {
  45         RescaleAlphaTest test = new RescaleAlphaTest();
  46         test.startTest();
  47     }
  48 
  49     private void startTest() throws Exception {
  50 
  51         // Test with source image with alpha channel
  52 
  53         bimg = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
  54         Graphics2D g2d = bimg.createGraphics();
  55         g2d.setColor(Color.GREEN);
  56         g2d.fillRect(0, 0, w, h);
  57 
  58         RescaleOp res = new RescaleOp(scaleFactor, offset, null);
  59         bimg1 = res.filter(bimg, null);
  60 
  61         // check if destination image has alpha channel copied from src
  62         checkForAlpha(bimg1);
  63 
  64         // Test with source image without alpha channel
  65         bimg = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
  66         g2d = bimg.createGraphics();
  67         g2d.setColor(Color.GREEN);
  68         g2d.fillRect(0, 0, w, h);
  69 
  70 
  71         res = new RescaleOp(scaleFactor, offset, null);
  72 
  73         // Create destination image with alpha channel
  74         bimg1 = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
  75         bimg1 = res.filter(bimg, bimg1);
  76 
  77         // check if filtered destination image has alpha channel
  78         checkForAlpha(bimg1);
  79 
  80     }
  81 
  82     private void checkForAlpha(BufferedImage bi) throws IOException {
  83         int argb = bi.getRGB(w/2, h/2);
  84         if ((argb >>> 24) != 255) {
  85             throw new
  86             RuntimeException("Wrong alpha in destination image.RescaleOp with alpha failed.");
  87         }
  88     }
  89 }