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1   /*
2    * Copyright (C) 2010, Google Inc.
3    * and other copyright owners as documented in the project's IP log.
4    *
5    * This program and the accompanying materials are made available
6    * under the terms of the Eclipse Distribution License v1.0 which
7    * accompanies this distribution, is reproduced below, and is
8    * available at http://www.eclipse.org/org/documents/edl-v10.php
9    *
10   * All rights reserved.
11   *
12   * Redistribution and use in source and binary forms, with or
13   * without modification, are permitted provided that the following
14   * conditions are met:
15   *
16   * - Redistributions of source code must retain the above copyright
17   *   notice, this list of conditions and the following disclaimer.
18   *
19   * - Redistributions in binary form must reproduce the above
20   *   copyright notice, this list of conditions and the following
21   *   disclaimer in the documentation and/or other materials provided
22   *   with the distribution.
23   *
24   * - Neither the name of the Eclipse Foundation, Inc. nor the
25   *   names of its contributors may be used to endorse or promote
26   *   products derived from this software without specific prior
27   *   written permission.
28   *
29   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
30   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
31   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
34   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
35   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42   */
43  
44  package org.eclipse.jgit.internal.storage.file;
45  
46  import java.io.BufferedInputStream;
47  import java.io.IOException;
48  import java.io.InputStream;
49  import java.util.zip.InflaterInputStream;
50  
51  import org.eclipse.jgit.errors.LargeObjectException;
52  import org.eclipse.jgit.errors.MissingObjectException;
53  import org.eclipse.jgit.lib.ObjectId;
54  import org.eclipse.jgit.lib.ObjectLoader;
55  import org.eclipse.jgit.lib.ObjectStream;
56  
57  class LargePackedWholeObject extends ObjectLoader {
58  	private final int type;
59  
60  	private final long size;
61  
62  	private final long objectOffset;
63  
64  	private final int headerLength;
65  
66  	private final PackFile pack;
67  
68  	private final FileObjectDatabase db;
69  
70  	LargePackedWholeObject(int type, long size, long objectOffset,
71  			int headerLength, PackFile pack, FileObjectDatabase db) {
72  		this.type = type;
73  		this.size = size;
74  		this.objectOffset = objectOffset;
75  		this.headerLength = headerLength;
76  		this.pack = pack;
77  		this.db = db;
78  	}
79  
80  	/** {@inheritDoc} */
81  	@Override
82  	public int getType() {
83  		return type;
84  	}
85  
86  	/** {@inheritDoc} */
87  	@Override
88  	public long getSize() {
89  		return size;
90  	}
91  
92  	/** {@inheritDoc} */
93  	@Override
94  	public boolean isLarge() {
95  		return true;
96  	}
97  
98  	/** {@inheritDoc} */
99  	@Override
100 	public byte[] getCachedBytes() throws LargeObjectException {
101 		try {
102 			throw new LargeObjectException(getObjectId());
103 		} catch (IOException cannotObtainId) {
104 			throw new LargeObjectException(cannotObtainId);
105 		}
106 	}
107 
108 	/** {@inheritDoc} */
109 	@Override
110 	public ObjectStream openStream() throws MissingObjectException, IOException {
111 		WindowCursor wc = new WindowCursor(db);
112 		InputStream in;
113 		try {
114 			in = new PackInputStream(pack, objectOffset + headerLength, wc);
115 		} catch (IOException packGone) {
116 			// If the pack file cannot be pinned into the cursor, it
117 			// probably was repacked recently. Go find the object
118 			// again and open the stream from that location instead.
119 			//
120 			return wc.open(getObjectId(), type).openStream();
121 		}
122 
123 		in = new BufferedInputStream( //
124 				new InflaterInputStream( //
125 						in, //
126 						wc.inflater(), //
127 						8192), //
128 				8192);
129 		return new ObjectStream.Filter(type, size, in);
130 	}
131 
132 	private ObjectId getObjectId() throws IOException {
133 		return pack.findObjectForOffset(objectOffset);
134 	}
135 }