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.ObjectIdOwnerMap;
49
50 /**
51 * Description of an object stored in a pack file, including offset.
52 * <p>
53 * When objects are stored in packs Git needs the ObjectId and the offset
54 * (starting position of the object data) to perform random-access reads of
55 * objects from the pack. This extension of ObjectId includes the offset.
56 */
57 public class PackedObjectInfo extends ObjectIdOwnerMap.Entry {
58 private long offset;
59
60 private int crc;
61
62 PackedObjectInfo(final long headerOffset, final int packedCRC,
63 final AnyObjectId id) {
64 super(id);
65 offset = headerOffset;
66 crc = packedCRC;
67 }
68
69 /**
70 * Create a new structure to remember information about an object.
71 *
72 * @param id
73 * the identity of the object the new instance tracks.
74 */
75 public PackedObjectInfo(final AnyObjectId id) {
76 super(id);
77 }
78
79 /**
80 * @return offset in pack when object has been already written, or 0 if it
81 * has not been written yet
82 */
83 public long getOffset() {
84 return offset;
85 }
86
87 /**
88 * Set the offset in pack when object has been written to.
89 *
90 * @param offset
91 * offset where written object starts
92 */
93 public void setOffset(final long offset) {
94 this.offset = offset;
95 }
96
97 /**
98 * @return the 32 bit CRC checksum for the packed data.
99 */
100 public int getCRC() {
101 return crc;
102 }
103
104 /**
105 * Record the 32 bit CRC checksum for the packed data.
106 *
107 * @param crc
108 * checksum of all packed data (including object type code,
109 * inflated length and delta base reference) as computed by
110 * {@link java.util.zip.CRC32}.
111 */
112 public void setCRC(final int crc) {
113 this.crc = crc;
114 }
115 }