GitSharp/AbstractObject.cs

   1 /*
   2  * Copyright (C) 2009, Henon <meinrad.recheis@gmail.com>
   3  *
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or
   7  * without modification, are permitted provided that the following
   8  * conditions are met:
   9  *
  10  * - Redistributions of source code must retain the above copyright
  11  *   notice, this list of conditions and the following disclaimer.
  12  *
  13  * - Redistributions in binary form must reproduce the above
  14  *   copyright notice, this list of conditions and the following
  15  *   disclaimer in the documentation and/or other materials provided
  16  *   with the distribution.
  17  *
  18  * - Neither the name of the Git Development Community nor the
  19  *   names of its contributors may be used to endorse or promote
  20  *   products derived from this software without specific prior
  21  *   written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  24  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  25  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  31  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  32  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  35  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 using System;
  39 using System.Collections.Generic;
  40 using System.Linq;
  41 using System.Text;
  42
  43 using ObjectId = GitSharp.Core.ObjectId;
  44 using CoreRef = GitSharp.Core.Ref;
  45 using CoreCommit = GitSharp.Core.Commit;
  46 using CoreTree = GitSharp.Core.Tree;
  47 using CoreTag = GitSharp.Core.Tag;
  48 using System.Diagnostics;
  49
  50 namespace GitSharp
  51 {
  52         /// <summary>
  53         /// AbstractObject is the base class for the classes Blob, Commit, Tag and Tree. It proviedes test methods
  54         /// to identify its specialized type (i.e. IsBlob, IsCommit, etc). AbstractObject also defines comparison operators so you can
  55         /// safely compare git objects by using the operators == or != which internally efficiently compare the objects hashes.
  56         /// </summary>
  57         public abstract class AbstractObject
  58         {
  59                 protected Repository _repo;
  60                 internal ObjectId _id; // <--- the git object is lazy loaded. only a _id is required until properties are accessed.
  61
  62                 internal AbstractObject(Repository repo, ObjectId id)
  63                 {
  64                         _repo = repo;
  65                         _id = id;
  66                 }
  67
  68                 internal AbstractObject(Repository repo, string name)
  69                 {
  70                         _repo = repo;
  71                         _id = _repo._internal_repo.Resolve(name);
  72                 }
  73
  74                 /// <summary>
  75                 /// The git object's SHA1 hash. This is the long hash, See ShortHash for the abbreviated version.
  76                 /// </summary>
  77                 public string Hash
  78                 {
  79                         get
  80                         {
  81                                 if (_id == null)
  82                                         return null;
  83                                 return _id.Name;
  84                         }
  85                 }
  86
  87                 /// <summary>
  88                 /// The git object's abbreviated SHA1 hash.
  89                 /// </summary>
  90                 public string ShortHash
  91                 {
  92                         get
  93                         {
  94                                 if (_id == null)
  95                                         return null;
  96                                 return _id.Abbreviate(_repo._internal_repo).name();
  97                         }
  98                 }
  99
 100                 /// <summary>
 101                 /// True if this object is a Blob (or Leaf which is a subclass of Blob).
 102                 /// </summary>
 103                 public virtual bool IsBlob
 104                 {
 105                         get
 106                         {
 107                                 if (_id == null)
 108                                         return false;
 109                                 return _repo._internal_repo.MapObject(_id, null) is byte[];
 110                         }
 111                 }
 112
 113                 /// <summary>
 114                 /// True if this object is a Commit.
 115                 /// </summary>
 116                 public virtual bool IsCommit
 117                 {
 118                         get
 119                         {
 120                                 if (_id == null)
 121                                         return false;
 122                                 return _repo._internal_repo.MapObject(_id, null) is CoreCommit;
 123                         }
 124                 }
 125
 126                 /// <summary>
 127                 /// True if this object is a Tag.
 128                 /// </summary>
 129                 public virtual bool IsTag
 130                 {
 131                         get
 132                         {
 133                                 if (_id == null)
 134                                         return false;
 135                                 return _repo._internal_repo.MapObject(_id, null) is CoreTag;
 136                         }
 137                 }
 138
 139                 /// <summary>
 140                 /// True if the internal object is a Tree.
 141                 /// </summary>
 142                 public virtual bool IsTree
 143                 {
 144                         get
 145                         {
 146                                 if (_id == null)
 147                                         return false;
 148                                 return _repo._internal_repo.MapObject(_id, null) is CoreTree;
 149                         }
 150                 }
 151
 152                 /// <summary>
 153                 /// The repository where this git object belongs to.
 154                 /// </summary>
 155                 public Repository Repository
 156                 {
 157                         get
 158                         {
 159                                 return _repo;
 160                         }
 161                 }
 162
 163 #if implemented
 164         public Diff Diff(AbstractObject other) { }
 165
 166         public ?? Grep(?? pattern) { }
 167
 168         public Byte[] Content { get; }
 169
 170         public long Size { get; }
 171 #endif
 172
 173                 /// <summary>
 174                 /// Internal helper function to create the right object instance for a given hash
 175                 /// </summary>
 176                 /// <param name="repo"></param>
 177                 /// <param name="objectId"></param>
 178                 /// <returns></returns>
 179                 internal static AbstractObject Wrap(Repository repo, ObjectId objectId)
 180                 {
 181                         Debug.Assert(objectId != null, "ObjectId is null");
 182                         Debug.Assert(repo != null, "Repository is null");
 183                         var obj = repo._internal_repo.MapObject(objectId, null);
 184                         if (obj is CoreCommit)
 185                                 return new Commit(repo, obj as CoreCommit);
 186                         else if (obj is CoreTag)
 187                                 return new Tag(repo, obj as CoreTag);
 188                         else if (obj is CoreTree)
 189                                 return new Tree(repo, obj as CoreTree);
 190                         else if (obj is byte[])
 191                                 return new Blob(repo, objectId, obj as byte[]);
 192                         else
 193                         {
 194                                 //Debug.Assert(false, "What kind of object do we have here?");
 195                                 return null;
 196                         }
 197                 }
 198
 199                 #region Equality overrides
 200
 201                 /// <summary>
 202                 /// Overriding equals to reflect that different AbstractObject instances with the same hash are in fact equal.
 203                 /// </summary>
 204                 /// <param name="obj"></param>
 205                 /// <returns></returns>
 206                 public override bool Equals(object obj)
 207                 {
 208                         if (obj is AbstractObject)
 209                                 return _id == (obj as AbstractObject)._id;
 210                         else
 211                                 return false;
 212                 }
 213
 214                 public static bool operator ==(AbstractObject self, object other)
 215                 {
 216                         return Equals(self, other);
 217                 }
 218
 219                 public static bool operator !=(AbstractObject self, object other)
 220                 {
 221                         return !(self == other);
 222                 }
 223
 224                 public override int GetHashCode()
 225                 {
 226                         if (_id != null)
 227                                 return _id.GetHashCode();
 228                         return base.GetHashCode();
 229                 }
 230
 231                 #endregion
 232
 233         }
 234 }