PackedObjectInfo.java

  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. package org.eclipse.jgit.transport;

  45. import org.eclipse.jgit.lib.AnyObjectId;
  46. import org.eclipse.jgit.lib.Constants;
  47. import org.eclipse.jgit.lib.ObjectIdOwnerMap;

  48. /**
  49.  * Description of an object stored in a pack file, including offset.
  50.  * <p>
  51.  * When objects are stored in packs Git needs the ObjectId and the offset
  52.  * (starting position of the object data) to perform random-access reads of
  53.  * objects from the pack. This extension of ObjectId includes the offset.
  54.  */
  55. public class PackedObjectInfo extends ObjectIdOwnerMap.Entry {
  56.     private long offset;

  57.     private int crc;

  58.     private int type = Constants.OBJ_BAD;

  59.     PackedObjectInfo(final long headerOffset, final int packedCRC,
  60.             final AnyObjectId id) {
  61.         super(id);
  62.         offset = headerOffset;
  63.         crc = packedCRC;
  64.     }

  65.     /**
  66.      * Create a new structure to remember information about an object.
  67.      *
  68.      * @param id
  69.      *            the identity of the object the new instance tracks.
  70.      */
  71.     public PackedObjectInfo(AnyObjectId id) {
  72.         super(id);
  73.     }

  74.     /**
  75.      * Get offset in pack when object has been already written
  76.      *
  77.      * @return offset in pack when object has been already written, or 0 if it
  78.      *         has not been written yet
  79.      */
  80.     public long getOffset() {
  81.         return offset;
  82.     }

  83.     /**
  84.      * Set the offset in pack when object has been written to.
  85.      *
  86.      * @param offset
  87.      *            offset where written object starts
  88.      */
  89.     public void setOffset(long offset) {
  90.         this.offset = offset;
  91.     }

  92.     /**
  93.      * Get the 32 bit CRC checksum for the packed data.
  94.      *
  95.      * @return the 32 bit CRC checksum for the packed data.
  96.      */
  97.     public int getCRC() {
  98.         return crc;
  99.     }

  100.     /**
  101.      * Record the 32 bit CRC checksum for the packed data.
  102.      *
  103.      * @param crc
  104.      *            checksum of all packed data (including object type code,
  105.      *            inflated length and delta base reference) as computed by
  106.      *            {@link java.util.zip.CRC32}.
  107.      */
  108.     public void setCRC(int crc) {
  109.         this.crc = crc;
  110.     }

  111.     /**
  112.      * Get the object type.
  113.      *
  114.      * @return the object type. The default type is OBJ_BAD, which is considered
  115.      *         as unknown or invalid type.
  116.      * @since 4.9
  117.      */
  118.     public int getType() {
  119.         return type;
  120.     }

  121.     /**
  122.      * Record the object type if applicable.
  123.      *
  124.      * @param type
  125.      *            the object type.
  126.      * @since 4.9
  127.      */
  128.     public void setType(int type) {
  129.         this.type = type;
  130.     }
  131. }