InversionOfControl/Castle.MicroKernel/Handlers/DefaultGenericHandler.cs

   1 // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.MicroKernel.Handlers
  16 {
  17         using System;
  18         using System.Collections.Generic;
  19         using Core;
  20
  21         /// <summary>
  22         /// Summary description for DefaultGenericHandler.
  23         /// </summary>
  24         /// <remarks>
  25         /// TODO: Consider refactoring AbstractHandler moving lifestylemanager
  26         /// creation to DefaultHandler
  27         /// </remarks>
  28         [Serializable]
  29         public class DefaultGenericHandler : AbstractHandler
  30         {
  31                 private readonly IDictionary<Type, IHandler> type2SubHandler;
  32
  33                 /// <summary>
  34                 /// Initializes a new instance of the <see cref="DefaultGenericHandler"/> class.
  35                 /// </summary>
  36                 /// <param name="model"></param>
  37                 public DefaultGenericHandler(ComponentModel model)
  38                         : base(model)
  39                 {
  40                         type2SubHandler = new Dictionary<Type, IHandler>();
  41                 }
  42
  43                 public override object Resolve(CreationContext context)
  44                 {
  45                         Type implType = ComponentModel.Implementation.MakeGenericType(context.GenericArguments);
  46
  47                         IHandler handler = GetSubHandler(context, implType);
  48
  49                         //so the generic version wouldn't be considered as well
  50                         using (context.ResolvingHandler(this))
  51                         {
  52                                 return handler.Resolve(context);
  53                         }
  54                 }
  55
  56                 public override void Release(object instance)
  57                 {
  58                         IHandler handler = GetSubHandler(CreationContext.Empty, instance.GetType());
  59
  60                         handler.Release(instance);
  61                 }
  62
  63                 protected IHandler GetSubHandler(CreationContext context, Type genericType)
  64                 {
  65                         lock (type2SubHandler)
  66                         {
  67                                 IHandler handler;
  68
  69                                 if (type2SubHandler.ContainsKey(genericType))
  70                                 {
  71                                         handler = type2SubHandler[genericType];
  72                                 }
  73                                 else
  74                                 {
  75                                         Type service = ComponentModel.Service.MakeGenericType(context.GenericArguments);
  76
  77                                         ComponentModel newModel = Kernel.ComponentModelBuilder.BuildModel(
  78                                                 ComponentModel.Name, service, genericType, null);
  79
  80                                         newModel.ExtendedProperties[ComponentModel.SkipRegistration] = true;
  81
  82                                         CloneParentProperties(newModel);
  83
  84                                         Kernel.AddCustomComponent(newModel);
  85
  86                                         handler = Kernel.HandlerFactory.Create(newModel);
  87
  88                                         type2SubHandler[genericType] = handler;
  89                                 }
  90
  91                                 return handler;
  92                         }
  93                 }
  94
  95                 /// <summary>
  96                 /// Clone some of the parent componentmodel properties to the generic subhandler.
  97                 /// </summary>
  98                 /// <remarks>
  99                 /// The following properties are copied:
 100                 /// <list type="bullet">
 101                 /// <item>
 102                 ///             <description>The <see cref="LifestyleType"/></description>
 103                 /// </item>
 104                 /// <item>
 105                 ///             <description>The <see cref="ComponentModel.Interceptors"/></description>
 106                 /// </item>
 107                 /// </list>
 108                 /// </remarks>
 109                 /// <param name="newModel">the subhandler</param>
 110                 private void CloneParentProperties(ComponentModel newModel)
 111                 {
 112                         // Inherits from LifeStyle's context.
 113                         newModel.LifestyleType = ComponentModel.LifestyleType;
 114
 115                         // Inherit the parent handler interceptors.
 116                         foreach (InterceptorReference interceptor in ComponentModel.Interceptors)
 117                         {
 118                                 // we need to check that we are not adding the inteceptor again, if it was added
 119                                 // by a facility already
 120                                 newModel.Interceptors.AddIfNotInCollection(interceptor);
 121                         }
 122                 }
 123         }
 124 }