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1   /**
2    * Copyright (c) 2011, The University of Southampton and the individual contributors.
3    * All rights reserved.
4    *
5    * Redistribution and use in source and binary forms, with or without modification,
6    * are permitted provided that the following conditions are met:
7    *
8    *   * 	Redistributions of source code must retain the above copyright notice,
9    * 	this list of conditions and the following disclaimer.
10   *
11   *   *	Redistributions in binary form must reproduce the above copyright notice,
12   * 	this list of conditions and the following disclaimer in the documentation
13   * 	and/or other materials provided with the distribution.
14   *
15   *   *	Neither the name of the University of Southampton nor the names of its
16   * 	contributors may be used to endorse or promote products derived from this
17   * 	software without specific prior written permission.
18   *
19   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
20   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
23   * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
26   * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
28   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29   */
30  package org.openimaj.video.xuggle;
31  
32  import java.io.File;
33  import java.io.IOException;
34  import java.net.URL;
35  import java.util.HashMap;
36  import java.util.Map;
37  
38  import org.apache.commons.io.FileUtils;
39  
40  import com.xuggle.xuggler.io.FileProtocolHandler;
41  import com.xuggle.xuggler.io.IURLProtocolHandler;
42  
43  /**
44   * An {@link IURLProtocolHandler} for jar resources. This implementation copies
45   * the resource to a temporary file before opening it - it could potentially
46   * consume a stream directly, but this would restrict the video codecs to ones
47   * that directly support streaming.
48   *
49   * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
50   */
51  public class JarURLProtocolHandler extends FileProtocolHandler {
52  	private static final Map<URL, String> extractedVideos = new HashMap<URL, String>();
53  
54  	/**
55  	 * Construct with no video
56  	 */
57  	public JarURLProtocolHandler() {
58  
59  	}
60  
61  	/**
62  	 * Construct with the given url. The video will be extracted immediately.
63  	 *
64  	 * @param url
65  	 *            the url to the video
66  	 * @throws IOException
67  	 *             if an error occurs
68  	 */
69  	public JarURLProtocolHandler(String url) throws IOException {
70  		super(extract(url));
71  	}
72  
73  	@Override
74  	public int open(String url, int flags) {
75  		if (flags != URL_RDONLY_MODE) {
76  			// log.debug("Cannot write to a video in a jar file");
77  			return -1;
78  		}
79  
80  		try {
81  			return super.open(extract(url), flags);
82  		} catch (final IOException e) {
83  			// log.error("Unexpected IOException: " + e);
84  			e.printStackTrace();
85  			return -1;
86  		}
87  	}
88  
89  	private static String extract(String urlString) throws IOException {
90  		final URL url = new URL(urlString);
91  
92  		if (extractedVideos.containsKey(url))
93  			return extractedVideos.get(url);
94  
95  		final File tmp = File.createTempFile("movie", ".tmp");
96  		final String filename = tmp.toURI().toString();
97  		// log.debug("Mapping url " + urlString + " to  file " + tmp);
98  		tmp.deleteOnExit();
99  		FileUtils.copyURLToFile(url, tmp);
100 		extractedVideos.put(url, filename);
101 
102 		return filename;
103 	}
104 
105 	@Override
106 	public int write(byte[] paramArrayOfByte, int paramInt) {
107 		// writing not supported
108 		return -1;
109 	}
110 }