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.pack;
45
46 import org.eclipse.jgit.lib.ObjectId;
47
48 /**
49 * An object representation {@link PackWriter} can consider for packing.
50 */
51 public class StoredObjectRepresentation {
52 /** Special unknown value for {@link #getWeight()}. */
53 public static final int WEIGHT_UNKNOWN = Integer.MAX_VALUE;
54
55 /** Stored in pack format, as a delta to another object. */
56 public static final int PACK_DELTA = 0;
57
58 /** Stored in pack format, without delta. */
59 public static final int PACK_WHOLE = 1;
60
61 /** Only available after inflating to canonical format. */
62 public static final int FORMAT_OTHER = 2;
63
64 /**
65 * @return relative size of this object's packed form. The special value
66 * {@link #WEIGHT_UNKNOWN} can be returned to indicate the
67 * implementation doesn't know, or cannot supply the weight up
68 * front.
69 */
70 public int getWeight() {
71 return WEIGHT_UNKNOWN;
72 }
73
74 /**
75 * @return the storage format type, which must be one of
76 * {@link #PACK_DELTA}, {@link #PACK_WHOLE}, or
77 * {@link #FORMAT_OTHER}.
78 */
79 public int getFormat() {
80 return FORMAT_OTHER;
81 }
82
83 /**
84 * @return identity of the object this delta applies to in order to recover
85 * the original object content. This method should only be called if
86 * {@link #getFormat()} returned {@link #PACK_DELTA}.
87 */
88 public ObjectId getDeltaBase() {
89 return null;
90 }
91
92 /**
93 * @return whether the current representation of the object has had delta
94 * compression attempted on it.
95 */
96 public boolean wasDeltaAttempted() {
97 int fmt = getFormat();
98 return fmt == PACK_DELTA || fmt == PACK_WHOLE;
99 }
100 }