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1   /*
2    * Copyright (c) 2001, 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.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package com.sun.imageio.plugins.jpeg;
27  
28  import javax.imageio.metadata.IIOInvalidTreeException;
29  import javax.imageio.metadata.IIOMetadataNode;
30  import javax.imageio.stream.ImageOutputStream;
31  
32  import java.io.IOException;
33  
34  import org.w3c.dom.Node;
35  
36  /**
37       * A DRI (Define Restart Interval) marker segment.
38       */
39  class DRIMarkerSegment extends MarkerSegment {
40      /**
41       * Restart interval, or 0 if none is specified.
42       */
43      int restartInterval = 0;
44  
45      DRIMarkerSegment(JPEGBuffer buffer)
46          throws IOException {
47          super(buffer);
48          restartInterval = (buffer.buf[buffer.bufPtr++] & 0xff) << 8;
49          restartInterval |= buffer.buf[buffer.bufPtr++] & 0xff;
50          buffer.bufAvail -= length;
51      }
52  
53      DRIMarkerSegment(Node node) throws IIOInvalidTreeException {
54          super(JPEG.DRI);
55          updateFromNativeNode(node, true);
56      }
57  
58      IIOMetadataNode getNativeNode() {
59          IIOMetadataNode node = new IIOMetadataNode("dri");
60          node.setAttribute("interval", Integer.toString(restartInterval));
61          return node;
62      }
63  
64      void updateFromNativeNode(Node node, boolean fromScratch)
65          throws IIOInvalidTreeException {
66          restartInterval = getAttributeValue(node, null, "interval",
67                                              0, 65535, true);
68      }
69  
70      /**
71       * Writes the data for this segment to the stream in
72       * valid JPEG format.
73       */
74      void write(ImageOutputStream ios) throws IOException {
75          // We don't write DRI segments; the IJG library does.
76      }
77  
78      void print() {
79          printTag("DRI");
80          System.out.println("Interval: "
81                             + Integer.toString(restartInterval));
82      }
83  }