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1   /*
2    * Copyright (C) 2008-2009, Robin Rosenberg <robin.rosenberg@dewire.com>
3    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
4    * and other copyright owners as documented in the project's IP log.
5    *
6    * This program and the accompanying materials are made available
7    * under the terms of the Eclipse Distribution License v1.0 which
8    * accompanies this distribution, is reproduced below, and is
9    * available at http://www.eclipse.org/org/documents/edl-v10.php
10   *
11   * All rights reserved.
12   *
13   * Redistribution and use in source and binary forms, with or
14   * without modification, are permitted provided that the following
15   * conditions are met:
16   *
17   * - Redistributions of source code must retain the above copyright
18   *   notice, this list of conditions and the following disclaimer.
19   *
20   * - Redistributions in binary form must reproduce the above
21   *   copyright notice, this list of conditions and the following
22   *   disclaimer in the documentation and/or other materials provided
23   *   with the distribution.
24   *
25   * - Neither the name of the Eclipse Foundation, Inc. nor the
26   *   names of its contributors may be used to endorse or promote
27   *   products derived from this software without specific prior
28   *   written permission.
29   *
30   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
31   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
32   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
35   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
37   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
38   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
39   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
41   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
42   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43   */
44  
45  package org.eclipse.jgit.transport;
46  
47  import org.eclipse.jgit.lib.AnyObjectId;
48  import org.eclipse.jgit.lib.Constants;
49  import org.eclipse.jgit.lib.ObjectIdOwnerMap;
50  
51  /**
52   * Description of an object stored in a pack file, including offset.
53   * <p>
54   * When objects are stored in packs Git needs the ObjectId and the offset
55   * (starting position of the object data) to perform random-access reads of
56   * objects from the pack. This extension of ObjectId includes the offset.
57   */
58  public class PackedObjectInfo extends ObjectIdOwnerMap.Entry {
59  	private long offset;
60  
61  	private int crc;
62  
63  	private int type = Constants.OBJ_BAD;
64  
65  	PackedObjectInfo(final long headerOffset, final int packedCRC,
66  			final AnyObjectId id) {
67  		super(id);
68  		offset = headerOffset;
69  		crc = packedCRC;
70  	}
71  
72  	/**
73  	 * Create a new structure to remember information about an object.
74  	 *
75  	 * @param id
76  	 *            the identity of the object the new instance tracks.
77  	 */
78  	public PackedObjectInfo(AnyObjectId id) {
79  		super(id);
80  	}
81  
82  	/**
83  	 * Get offset in pack when object has been already written
84  	 *
85  	 * @return offset in pack when object has been already written, or 0 if it
86  	 *         has not been written yet
87  	 */
88  	public long getOffset() {
89  		return offset;
90  	}
91  
92  	/**
93  	 * Set the offset in pack when object has been written to.
94  	 *
95  	 * @param offset
96  	 *            offset where written object starts
97  	 */
98  	public void setOffset(long offset) {
99  		this.offset = offset;
100 	}
101 
102 	/**
103 	 * Get the 32 bit CRC checksum for the packed data.
104 	 *
105 	 * @return the 32 bit CRC checksum for the packed data.
106 	 */
107 	public int getCRC() {
108 		return crc;
109 	}
110 
111 	/**
112 	 * Record the 32 bit CRC checksum for the packed data.
113 	 *
114 	 * @param crc
115 	 *            checksum of all packed data (including object type code,
116 	 *            inflated length and delta base reference) as computed by
117 	 *            {@link java.util.zip.CRC32}.
118 	 */
119 	public void setCRC(int crc) {
120 		this.crc = crc;
121 	}
122 
123 	/**
124 	 * Get the object type.
125 	 *
126 	 * @return the object type. The default type is OBJ_BAD, which is considered
127 	 *         as unknown or invalid type.
128 	 * @since 4.9
129 	 */
130 	public int getType() {
131 		return type;
132 	}
133 
134 	/**
135 	 * Record the object type if applicable.
136 	 *
137 	 * @param type
138 	 *            the object type.
139 	 * @since 4.9
140 	 */
141 	public void setType(int type) {
142 		this.type = type;
143 	}
144 }