mcs/class/corlib/System.Runtime.Serialization/SerializationObjectManager.cs

   1 //
   2 // System.Runtime.Serialization.SerializationObjectManager.cs
   3 //
   4 // Author:
   5 //   Robert Jordan (robertj@gmx.net)
   6 //
   7 // Copyright (C) 2006 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Collections;
  31
  32 namespace System.Runtime.Serialization {
  33
  34         public sealed class SerializationObjectManager
  35         {
  36                 readonly StreamingContext context;
  37                 readonly Hashtable seen = new Hashtable (HashHelper.Instance, HashHelper.Instance);
  38
  39                 event SerializationCallbacks.CallbackHandler callbacks;
  40
  41                 public SerializationObjectManager (StreamingContext context)
  42                 {
  43                         this.context = context;
  44                 }
  45
  46                 public void RegisterObject (object obj)
  47                 {
  48                         if (seen.Contains (obj))
  49                                 return;
  50
  51                         SerializationCallbacks sc = SerializationCallbacks
  52                                 .GetSerializationCallbacks (obj.GetType ());
  53
  54                         seen [obj] = HashHelper.NonNullObject;
  55                         sc.RaiseOnSerializing (obj, context);
  56
  57                         if (sc.HasSerializedCallbacks) {
  58                                 // record for later invocation
  59                                 callbacks += delegate (StreamingContext ctx)
  60                                 {
  61                                         sc.RaiseOnSerialized (obj, ctx);
  62                                 };
  63                         }
  64                 }
  65
  66                 public void RaiseOnSerializedEvent ()
  67                 {
  68                         if (callbacks != null)
  69                                 callbacks (context);
  70                 }
  71
  72                 class HashHelper : IHashCodeProvider, IComparer {
  73                         public static object NonNullObject = new object ();
  74                         public static HashHelper Instance = new HashHelper ();
  75
  76                         private HashHelper ()
  77                         {
  78                         }
  79
  80                         public int GetHashCode (object obj)
  81                         {
  82                                 if (obj == null)
  83                                         return 0;
  84                                 return Object.InternalGetHashCode (obj);
  85                         }
  86
  87                         public int Compare (object x, object y)
  88                         {
  89                                 return Object.ReferenceEquals (x, y) ? 0 : 1;
  90                         }
  91                 }
  92         }
  93 }
  94