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.Generic;
  31
  32 namespace System.Runtime.Serialization {
  33
  34         public sealed class SerializationObjectManager
  35         {
  36                 readonly StreamingContext context;
  37                 readonly List<WeakReference> seen;
  38
  39                 event SerializationCallbacks.CallbackHandler callbacks;
  40
  41                 public SerializationObjectManager (StreamingContext context)
  42                 {
  43                         this.seen = new List<WeakReference> ();
  44                         this.context = context;
  45                 }
  46
  47                 public void RegisterObject (object obj)
  48                 {
  49                         if (SeenObject (obj))
  50                                 return;
  51
  52                         SerializationCallbacks sc = SerializationCallbacks
  53                                 .GetSerializationCallbacks (obj.GetType ());
  54
  55                         seen.Add (new WeakReference (obj));
  56                         sc.RaiseOnSerializing (obj, context);
  57
  58                         if (sc.HasSerializedCallbacks) {
  59                                 // record for later invocation
  60                                 callbacks += delegate (StreamingContext ctx)
  61                                 {
  62                                         sc.RaiseOnSerialized (obj, ctx);
  63                                 };
  64                         }
  65                 }
  66
  67                 bool SeenObject (object obj)
  68                 {
  69                         if (obj == null)
  70                                 return true;
  71
  72                         int max = seen.Count;
  73                         for (int i = 0; i < max; i++) {
  74                                 object o = seen [i].Target;
  75                                 if (o == null) {
  76                                         seen.RemoveAt (i);
  77                                         i--;
  78                                         max--;
  79                                 } else if (o == obj) {
  80                                         return true;
  81                                 }
  82                         }
  83                         return false;
  84                 }
  85
  86                 public void RaiseOnSerializedEvent ()
  87                 {
  88                         if (callbacks != null)
  89                                 callbacks (context);
  90                 }
  91         }
  92 }
  93