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1   /**
2    * This file Copyright (c) 2009-2016 Magnolia International
3    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
4    *
5    *
6    * This file is dual-licensed under both the Magnolia
7    * Network Agreement and the GNU General Public License.
8    * You may elect to use one or the other of these licenses.
9    *
10   * This file is distributed in the hope that it will be
11   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12   * implied warranty of MERCHANTABILITY or FITNESS FOR A
13   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14   * Redistribution, except as permitted by whichever of the GPL
15   * or MNA you select, is prohibited.
16   *
17   * 1. For the GPL license (GPL), you can redistribute and/or
18   * modify this file under the terms of the GNU General
19   * Public License, Version 3, as published by the Free Software
20   * Foundation.  You should have received a copy of the GNU
21   * General Public License, Version 3 along with this program;
22   * if not, write to the Free Software Foundation, Inc., 51
23   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24   *
25   * 2. For the Magnolia Network Agreement (MNA), this file
26   * and the accompanying materials are made available under the
27   * terms of the MNA which accompanies this distribution, and
28   * is available at http://www.magnolia-cms.com/mna.html
29   *
30   * Any modifications to this file must keep this entire header
31   * intact.
32   *
33   */
34  package info.magnolia.imaging;
35  
36  import info.magnolia.imaging.util.ImageUtil;
37  
38  import java.awt.image.BufferedImage;
39  import java.io.IOException;
40  import java.io.OutputStream;
41  import java.util.Iterator;
42  
43  import javax.imageio.IIOImage;
44  import javax.imageio.ImageIO;
45  import javax.imageio.ImageTypeSpecifier;
46  import javax.imageio.ImageWriteParam;
47  import javax.imageio.ImageWriter;
48  import javax.imageio.stream.ImageOutputStream;
49  
50  /**
51   * An ImageStreamer implementation which always generates the image.
52   * It also knows about some of the javax.imageio quirks, so other
53   * implementations should consider subclassing or wrapping it.
54   *
55   * @param <P> type of ParameterProvider's parameter
56   */
57  public class DefaultImageStreamer<P> extends AbstractImageStreamer<P> {
58  
59      @Override
60      public void serveImage(ImageGenerator<ParameterProvider<P>> generator, ParameterProvider<P> params, ImageResponse imageResponse) throws ImagingException, IOException {
61          final BufferedImage img = generator.generate(params);
62  
63          final OutputFormat outputFormat = generator.getOutputFormat(params);
64          imageResponse.setMediaType(getMediaType(outputFormat));
65  
66          // if source is transparent and format doesn't support transparency, we have to do some handy work
67          final BufferedImage fixedImg = ImageUtil.flattenTransparentImageForOpaqueFormat(img, outputFormat);
68  
69          write(fixedImg, imageResponse.getOutputStream(), outputFormat);
70      }
71  
72      protected void write(final BufferedImage img, final OutputStream out, final OutputFormat outputFormat) throws IOException {
73          // this is factored out of ImageIO.write() to allow customization of the ImageWriteParam
74          final ImageOutputStream imgOut = ImageIO.createImageOutputStream(out);
75          final ImageTypeSpecifier imgType = ImageTypeSpecifier.createFromRenderedImage(img);
76          final Iterator<ImageWriter> iter = ImageIO.getImageWriters(imgType, outputFormat.getFormatName());
77          if (!iter.hasNext()) {
78              throw new IllegalStateException("Can't find ImageWriter for " + outputFormat.getFormatName());
79          }
80          final ImageWriter imageWriter = iter.next();
81          final ImageWriteParam params = imageWriter.getDefaultWriteParam();
82  
83          outputFormat.applyTo(params);
84          imageWriter.setOutput(imgOut);
85  
86          imageWriter.write(null, new IIOImage(img, null, null), params);
87          imageWriter.dispose();
88          imgOut.flush();
89          imgOut.close();
90      }
91  
92  }