Castle IOC容器内幕故事（下）

太过爱你忘了你带给我的痛 2022-01-08 00:39 123阅读 0赞

摘要：上一篇文章我们了解了Castle IOC中注册组件的流程，为了更好的使用Castle IOC，本篇文章我们介绍一下Castle IOC中的几个重要的角色，开始Castle IOC容器内幕故事下角色介绍。

**主要内容**

1．ComponentModelBuilder 和 Contributors

2．Contributors分析

3．Handles分析

4．ComponentActivator分析

**一．ComponentModelBuilder 和 Contributors**

在前一篇中介绍组件的注册流程时说到了，创建ComponentModel的过程就是调用contributor来对组件进行处理的过程。Contributor就是我们这个内幕故事的第一个主角，在DefaultComponentModelBuilder一共注册了八个Contributor，每一个Contributor都专门负责处理某一方面的事情。如下代码所示：

![None.gif][] protected  virtual  void  InitializeContributors()  
![None.gif][]  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new ConfigurationModelInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new LifestyleModelInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new ConstructorDependenciesModelInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new PropertiesDependenciesModelInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new MethodMetaInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new LifecycleModelInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new ConfigurationParametersInspector() );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] AddContributor( new InterceptorInspector() );  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][]  
![None.gif][] //  http://terrylee.cnblogs.com

1．ConfigurationModelInspector：用来处理配置，它使用ConfigurationStore在Kernel中注册来保持一个组件的连接。

2．LifestyleModelInspector：生命周期处理方式，主要有Singleton、Thread、Transient、Pooled、Custom这些都可以在配置文件中指定，后续文章会讲到。

3．ConstructorDependenciesModelInspector：处理构造函数依赖，收集所有的Public构造函数，并它们交给ComponentModel的Constructors集合。

4．PropertiesDependenciesModelInspector：处理属性依赖，收集所有的可写的属性，Kernel也许不会在组件注册时就设置所有的属性，也有可能在请求获取组件时来设置。

5．MethodMetaInspector：检测组件配置中的Method节点，每一个节点都将添加到ComponentModel的Method集合中。

6．LifecycleModelInspector：处理组件生命周期，即在组件装载，初始化，销毁所出发的行为，分别对应三个接口：IInitializable,ISupportInitialize,IDisposable，如果组件实现了这些接口，容器会自动在不同的生命周期调用它们。

7．ConfigurationParametersInspector：处理配置文件中的parameters元素内容，每一个parameters都将创建一个ParameterModel，并添加到ComponentModel的Parameters集合中。

8．InterceptorInspector：处理InterceptorAttribute或者配置文件中的interceptors元素的信息。

在有些情况下，我们可能并不需要这么多的Contributors，或者说我们想添加自定义的Contributors，可以用ComponentModelBuilder的如下两个方法来实现对Contributors的管理：

![None.gif][] public  void  AddContributor(IContributeComponentModelConstruction contributor)  
![None.gif][]  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] contributors.Add(contributor);  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][]  
![None.gif][] public  void  RemoveContributor(IContributeComponentModelConstruction contributor)  
![None.gif][]  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] contributors.Remove(contributor);  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][]  
![None.gif][] //  http://terrylee.cnblogs.com

**二．** **Contributors** **分析**

通过上面的分析可以看到八个Contributors按一定顺序组合构成了整个组件的处理流程，现在我们来看一下Contributors是如何实现的？每一个Contributors都必须实现于接口IcontributeComponentModelConstruction，通过这个，我们可以创建自己的Contributors：

![None.gif][] public  interface  IContributeComponentModelConstruction  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]void ProcessModel(IKernel kernel, ComponentModel model);  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][] //  http://terrylee.cnblogs.com   
![None.gif][]

来看一下其中LifecycleModelInspector的实现代码：

![None.gif][] \[Serializable\]  
![None.gif][] public  class  LifecycleModelInspector : IContributeComponentModelConstruction  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]public LifecycleModelInspector()  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]publicvirtualvoid ProcessModel(IKernel kernel, ComponentModel model)  
![InBlock.gif][None.gif]  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif]if (typeof (IInitializable).IsAssignableFrom(model.Implementation))  
![InBlock.gif][None.gif]  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif] model.LifecycleSteps.Add( LifecycleStepType.Commission, InitializationConcern.Instance );  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]if (typeof (ISupportInitialize).IsAssignableFrom(model.Implementation))  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif] model.LifecycleSteps.Add( LifecycleStepType.Commission, SupportInitializeConcern.Instance );  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]if (typeof (IDisposable).IsAssignableFrom(model.Implementation))  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif] model.LifecycleSteps.Add( LifecycleStepType.Decommission, DisposalConcern.Instance );  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][] //  http://terrylee.cnblogs.com   
![None.gif][]

至此，第一个主角Contributors的故事就完了。

**三．Handles分析**

在组件注册流程中，还提到了一个重要的角色就是Handles。对Handles的描述引用Castle官方网站的一句话来说就是“They don't construct the component themselves, but they know who does”。Handles它有两个状态，分别标识组件是否可以被请求还是需要继续等待相关的依赖，所有的Handles都必须实现IHandles接口，通过这个也可以创建自己的Handle。

![None.gif][] public  enum  HandlerState  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif] Valid,  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] WaitingDependency  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][]  
![None.gif][] public  interface  IHandler  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]void Init(IKernel kernel);  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]object Resolve();  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]void Release(object instance);  
![InBlock.gif][None.gif]  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif] HandlerState CurrentState ![dot.gif][]\{ get; \}  
![InBlock.gif][None.gif]  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif] ComponentModel ComponentModel ![dot.gif][]\{ get; \}  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][] //  http://terrylee.cnblogs.com

Handles通过下面两个方法来检查哪些组件可以被请求，而哪些组件需要继续等待相关依赖，但是它并不做具体的组件创建工作。

![None.gif][] public  override  object  Resolve()  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]if (CurrentState == HandlerState.WaitingDependency)  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif] String message =  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] String.Format("Can't create component '\{1\}' as it has dependencies to be satisfied. \{0\}",  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] ObtainDependencyDetails(), ComponentModel.Name );  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]thrownew HandlerException(message);  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]return lifestyleManager.Resolve();  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][]  
![None.gif][] public  override  void  Release( object  instance)  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif] lifestyleManager.Release( instance );  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][] //  http://terrylee.cnblogs.com

**四．ComponentActivator分析**

介绍完前面三位角色之后，今天最后一位登场的主角就是ComponentActivator，组件激活器。每一个组件都和一个Activator相关联。Castle IOC为我们提供了默认的Activator，Castle IOC已经为我们提供了默认的Activator，但有时候也需要自己去实现Activator,比如说创建组件的实例并不是new出来的，而是通过我们自定义的Factory方法创建的，或者说我们需要创建的组件一个Remoting组件。创建自定义的Activator需要继承于AbstractComponentActivator基类或者DefaultComponentActivator。

![None.gif][] \[Serializable\]  
![None.gif][] public  abstract  class  AbstractComponentActivator : IComponentActivator  
![ExpandedBlockStart.gif][None.gif]![ContractedBlock.gif][None.gif] ![dot.gif][] \{  
![InBlock.gif][None.gif]private IKernel kernel;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]private ComponentModel model;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]private ComponentInstanceDelegate onCreation;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]private ComponentInstanceDelegate onDestruction;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]public AbstractComponentActivator(ComponentModel model, IKernel kernel,  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] ComponentInstanceDelegate onCreation,  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] ComponentInstanceDelegate onDestruction)  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif]this.model = model;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]this.kernel = kernel;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]this.onCreation = onCreation;  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]this.onDestruction = onDestruction;  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]public IKernel Kernel  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]get![dot.gif][]\{ return kernel; \}  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]public ComponentModel Model  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]get![dot.gif][]\{ return model; \}  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]public ComponentInstanceDelegate OnCreation  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]get![dot.gif][]\{ return onCreation; \}  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]public ComponentInstanceDelegate OnDestruction  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]get![dot.gif][]\{ return onDestruction; \}  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]protectedabstractobject InternalCreate();  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]protectedabstractvoid InternalDestroy(object instance);  
![InBlock.gif][None.gif]  
![ContractedSubBlock.gif][None.gif]![ExpandedSubBlockStart.gif][None.gif]IComponentActivator Members\#region IComponentActivator Members  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]publicvirtualobject Create()  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif]object instance = InternalCreate();  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] onCreation(model, instance);  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]return instance;  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif]publicvirtualvoid Destroy(object instance)  
![ExpandedSubBlockStart.gif][None.gif]![ContractedSubBlock.gif][None.gif]![dot.gif][]\{  
![InBlock.gif][None.gif] InternalDestroy(instance);  
![InBlock.gif][None.gif]  
![InBlock.gif][None.gif] onDestruction(model, instance);  
![InBlock.gif][None.gif]  
![ExpandedSubBlockEnd.gif][None.gif] \}  
![ExpandedSubBlockEnd.gif][None.gif]\#endregion  
![InBlock.gif][None.gif]  
![ExpandedBlockEnd.gif][None.gif]\}   
![None.gif][] //  http://terrylee.cnblogs.com

关于Castle IOC内部主角分析就到这里了，至此Castle IOC的内幕故事也告一段落了，通过这两篇文章我们对Castle IOC的内幕有了一个简单的认识，这对于我们使用Castle IOC有很大的好处，后续文章会讲到。

Castle IOC容器内幕故事（上）

**参考资料**

Castle的官方网站http://www.castleproject.org

转载于:https://www.cnblogs.com/Terrylee/archive/2006/04/19/378734.html

[None.gif]: 
[dot.gif]: /images/20211220/dd09bb2e79204b1baeac5d4136390d3a.png