《模式——工程化实现及扩展》（设计模式C# 版）《中介者模式 Mediator》——“自我检验" 参考答案
转自：《模式——工程化实现及扩展》（设计模式C# 版）
http://www.cnblogs.com/callwangxiang/
MarvellousWorks公司有A、B、C三个部门负责文件的拟稿、审批和备案，现有的流程如下：
1. A部门拟稿后将文件报B部门审核
2. B部门对于文件审核后，确认文件体例没有缺项后就通知C部门发布
3. 如果B部门发现文件体例有缺项时，将文件返回给A部门重新修改
4. C部门在接到B部门传来的文件时，先再发布，然后对其归档
不过，MarvellousWorks的管理层为了加强部门间文件流转的管理，正在酝酿修改工作流程：
1、 增加D部门专门负责归档，C部门将归档职责划入D部门后只负责发布文件
2、 C部门发布文件后也须先在D部门归档
3、 A、B部门间所有往复流转的中间文件也都报给D部门归档
请采用本章介绍的中介者模式及其扩展处理，将文件的流转调度过程从A、B、C、D各对象的职责中独立出来，并用单元测试验证不同的流转过程。
文件对象的定义
class Document
{
#region essential fields
public string Subject { get; set; }
public string Body { get; set; }
#endregion
#region optional fields
public string Comment { get; set; }
#endregion
public override string ToString()
{
return string.Format("\n[{0}]\n------------------\n{1}\n({2})\n", Subject, Body, Comment);
}
}
{
#region essential fields
public string Subject { get; set; }
public string Body { get; set; }
#endregion
#region optional fields
public string Comment { get; set; }
#endregion
public override string ToString()
{
return string.Format("\n[{0}]\n------------------\n{1}\n({2})\n", Subject, Body, Comment);
}
}
参考答案
分析第一步
上述A、B、C、D部门间的协作关系比较复杂，而且预期很快会变化，但协作的中间内容很简单——都是文件，所以采用事件方式，由.NET Framework自己的事件机制作为中介者相对很简单，而且类型间的依赖关系全都推给.NET Framework，为以后扩展更多参与方的协作关系提供便利。
据此，我们定义A、B、C、D时全部采用事件作为提供给外中介者协调响应关系的入口。
增加如下类型
class DocumentEventArgs : EventArgs
{
Document document;
public DocumentEventArgs(Document document)
{
this.document = document;
}
public Document Document{get{ return document;}}
}
abstract class Department
{
protected Document document = new Document();
public Document Document
{
get{ return document;}
protected set{ document = value;}
}
}
{
Document document;
public DocumentEventArgs(Document document)
{
this.document = document;
}
public Document Document{get{ return document;}}
}
abstract class Department
{
protected Document document = new Document();
public Document Document
{
get{ return document;}
protected set{ document = value;}
}
}
分析第二步
如果直接通过事件重载操作符 +=和-=建立各Colleague的响应关系，需要重复编写代码，而且不能在系统上线后将这个工作交给管理员维护。
因此，考虑参考前面的Builder模式，增加一个基于配置动态维护维护事件响应关系的对象。
实现和单元测试验证
1、验证“分析第一步”的设想
/// <summary>
/// 测试手工定义事件中介者的交互关系
/// </summary>
[TestMethod]
public void TestManualDefineEventMediatorInSucceedBranch()
{
// 用事件配置松散的响应关系
a1.WriteDocumentFinishedHandler += b1.OnReceiveFileToReview;
b1.ReviewDocumentFailedHandler += a1.OnReviewFailed;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToPublish;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToArchive;
// 成功的路径
a1.Write("a", "b", "c");
// 验证修订后的内容曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("b", b1.Document.Body);
Assert.AreEqual<string>("c", b1.Document.Comment);
// 验证修订后的内容也曾经流转给了C
Assert.AreEqual<string>("a", c1.Document.Subject);
Assert.AreEqual<string>("b", c1.Document.Body);
Assert.AreEqual<string>("c", c1.Document.Comment);
}
/// 测试手工定义事件中介者的交互关系
/// </summary>
[TestMethod]
public void TestManualDefineEventMediatorInSucceedBranch()
{
// 用事件配置松散的响应关系
a1.WriteDocumentFinishedHandler += b1.OnReceiveFileToReview;
b1.ReviewDocumentFailedHandler += a1.OnReviewFailed;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToPublish;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToArchive;
// 成功的路径
a1.Write("a", "b", "c");
// 验证修订后的内容曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("b", b1.Document.Body);
Assert.AreEqual<string>("c", b1.Document.Comment);
// 验证修订后的内容也曾经流转给了C
Assert.AreEqual<string>("a", c1.Document.Subject);
Assert.AreEqual<string>("b", c1.Document.Body);
Assert.AreEqual<string>("c", c1.Document.Comment);
}
Output窗口
------ Test started: Assembly: Mediator.Tests.dll ------
A begin write
A write finished
[a]
------------------
b
(c)
B received doc from A to review
B begin review
B review succeed
C received doc to publish from B
C published
C received doc to archive from B
C archived
1 passed, 0 failed, 0 skipped, took 0.50 seconds (MSTest 10.0).
A begin write
A write finished
[a]
------------------
b
(c)
B received doc from A to review
B begin review
B review succeed
C received doc to publish from B
C published
C received doc to archive from B
C archived
1 passed, 0 failed, 0 skipped, took 0.50 seconds (MSTest 10.0).
/// <summary>
/// 测试手工定义事件中介者的交互关系
/// </summary>
[TestMethod]
public void TestManualDefineEventMediatorInFailedBranch()
{
// 用事件配置松散的响应关系
a1.WriteDocumentFinishedHandler += b1.OnReceiveFileToReview;
b1.ReviewDocumentFailedHandler += a1.OnReviewFailed;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToPublish;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToArchive;
// 失败的路径
a1.Write("a", "", "");
// 验证确实文档曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("", b1.Document.Body);
Assert.AreEqual<string>("", b1.Document.Comment);
// 验证文档并没有流转给C
Assert.IsNull(c1.Document.Subject);
Assert.IsNull(c1.Document.Body);
Assert.IsNull(c1.Document.Comment);
// 修正错误的内容，重新执行流程
a1.Write("a", "b", "c");
// 验证修订后的内容曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("b", b1.Document.Body);
Assert.AreEqual<string>("c", b1.Document.Comment);
// 验证修订后的内容也曾经流转给了C
Assert.AreEqual<string>("a", c1.Document.Subject);
Assert.AreEqual<string>("b", c1.Document.Body);
Assert.AreEqual<string>("c", c1.Document.Comment);
}
/// 测试手工定义事件中介者的交互关系
/// </summary>
[TestMethod]
public void TestManualDefineEventMediatorInFailedBranch()
{
// 用事件配置松散的响应关系
a1.WriteDocumentFinishedHandler += b1.OnReceiveFileToReview;
b1.ReviewDocumentFailedHandler += a1.OnReviewFailed;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToPublish;
b1.ReviewDocumentSucceedHandler += c1.OnReceiveFileToArchive;
// 失败的路径
a1.Write("a", "", "");
// 验证确实文档曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("", b1.Document.Body);
Assert.AreEqual<string>("", b1.Document.Comment);
// 验证文档并没有流转给C
Assert.IsNull(c1.Document.Subject);
Assert.IsNull(c1.Document.Body);
Assert.IsNull(c1.Document.Comment);
// 修正错误的内容，重新执行流程
a1.Write("a", "b", "c");
// 验证修订后的内容曾经流转给了B
Assert.AreEqual<string>("a", b1.Document.Subject);
Assert.AreEqual<string>("b", b1.Document.Body);
Assert.AreEqual<string>("c", b1.Document.Comment);
// 验证修订后的内容也曾经流转给了C
Assert.AreEqual<string>("a", c1.Document.Subject);
Assert.AreEqual<string>("b", c1.Document.Body);
Assert.AreEqual<string>("c", c1.Document.Comment);
}
Output窗口
------ Test started: Assembly: Mediator.Tests.dll ------
A begin write
A write finished
[a]
------------------
()
B received doc from A to review
B begin review
B review failed
A received doc review failed from B
A begin write
A write finished
[a]
------------------
b
(c)
B received doc from A to review
B begin review
B review succeed
C received doc to publish from B
C published
C received doc to archive from B
C archived
1 passed, 0 failed, 0 skipped, took 3.64 seconds (MSTest 10.0).
A begin write
A write finished
[a]
------------------
()
B received doc from A to review
B begin review
B review failed
A received doc review failed from B
A begin write
A write finished
[a]
------------------
b
(c)
B received doc from A to review
B begin review
B review succeed
C received doc to publish from B
C published
C received doc to archive from B
C archived
1 passed, 0 failed, 0 skipped, took 3.64 seconds (MSTest 10.0).
2、验证“分析第二部” 的设想
定义管理基于事件的中介关系Builder
class EventMediatorBuilder
{
class ConfigItem
{
public Type SourceType { get; set; }
public Type TargetType { get; set; }
public string SourceEventName { get; set; }
public string TargetHandlerMethodName { get; set; }
public override bool Equals(object obj)
{
if (obj == null) throw new ArgumentNullException("obj");
var target = (ConfigItem)obj;
return
SourceType == target.SourceType &&
TargetType == target.TargetType &&
string.Equals(SourceEventName, target.SourceEventName) &&
string.Equals(TargetHandlerMethodName, target.TargetHandlerMethodName);
}
}
IList<ConfigItem> config = new List<ConfigItem>();
public EventMediatorBuilder AddConfig(Type sourceType, Type targetType, string sourceEventName, string targetHandlerMethodName)
{
if (sourceType == null) throw new ArgumentNullException("sourceType");
if (targetType == null) throw new ArgumentNullException("targetType");
if (string.IsNullOrEmpty(sourceEventName)) throw new ArgumentNullException("sourceEventName");
if (string.IsNullOrEmpty(targetHandlerMethodName)) throw new ArgumentNullException("targetHandlerMethodName");
if (sourceType.GetEvent(sourceEventName) == null) throw new NotSupportedException(sourceEventName);
var item = new ConfigItem()
{
SourceType = sourceType,
TargetType = targetType,
SourceEventName = sourceEventName,
TargetHandlerMethodName = targetHandlerMethodName
};
if (!config.Contains(item))
config.Add(item);
return this;
}
public EventMediatorBuilder BuildAUpColleagues(params object[] colleagues)
{
if (colleagues == null) throw new ArgumentNullException("colleagues");
if (config.Count() == 0) return this; // 没有通信关系配置项
if (colleagues.Count() == 1) return this; // 没有需要配置的关联对象组
colleagues.ToList().ForEach(x => { if (x == null) throw new ArgumentNullException(); });
//// 限制：不支持一类对象的某个实例同时向另一类对象多个实例的通知
//if (colleagues.GroupBy(x => x.GetType()).Count() != colleagues.Count())
// throw new NotSupportedException();
foreach (var item in config)
{
var sources = colleagues.Where(x => x.GetType() == item.SourceType);
if ((sources == null) || (sources.Count() == 0))
continue;
var targets = colleagues.Where(x => x.GetType() == item.TargetType);
if ((targets == null) || (targets.Count() == 0))
continue;
var eventInfo = item.SourceType.GetEvent(item.SourceEventName);
if (eventInfo == null)
continue;
var methodInfo = item.TargetType.GetMethod(item.TargetHandlerMethodName, BindingFlags.Public | BindingFlags.Instance);
if (methodInfo == null)
continue;
// 绑定事件响应关系
foreach (var source in sources)
foreach (var target in targets)
eventInfo.AddEventHandler(source, Delegate.CreateDelegate(eventInfo.EventHandlerType, target, methodInfo));
}
return this;
}
}
{
class ConfigItem
{
public Type SourceType { get; set; }
public Type TargetType { get; set; }
public string SourceEventName { get; set; }
public string TargetHandlerMethodName { get; set; }
public override bool Equals(object obj)
{
if (obj == null) throw new ArgumentNullException("obj");
var target = (ConfigItem)obj;
return
SourceType == target.SourceType &&
TargetType == target.TargetType &&
string.Equals(SourceEventName, target.SourceEventName) &&
string.Equals(TargetHandlerMethodName, target.TargetHandlerMethodName);
}
}
IList<ConfigItem> config = new List<ConfigItem>();
public EventMediatorBuilder AddConfig(Type sourceType, Type targetType, string sourceEventName, string targetHandlerMethodName)
{
if (sourceType == null) throw new ArgumentNullException("sourceType");
if (targetType == null) throw new ArgumentNullException("targetType");
if (string.IsNullOrEmpty(sourceEventName)) throw new ArgumentNullException("sourceEventName");
if (string.IsNullOrEmpty(targetHandlerMethodName)) throw new ArgumentNullException("targetHandlerMethodName");
if (sourceType.GetEvent(sourceEventName) == null) throw new NotSupportedException(sourceEventName);
var item = new ConfigItem()
{
SourceType = sourceType,
TargetType = targetType,
SourceEventName = sourceEventName,
TargetHandlerMethodName = targetHandlerMethodName
};
if (!config.Contains(item))
config.Add(item);
return this;
}
public EventMediatorBuilder BuildAUpColleagues(params object[] colleagues)
{
if (colleagues == null) throw new ArgumentNullException("colleagues");
if (config.Count() == 0) return this; // 没有通信关系配置项
if (colleagues.Count() == 1) return this; // 没有需要配置的关联对象组
colleagues.ToList().ForEach(x => { if (x == null) throw new ArgumentNullException(); });
//// 限制：不支持一类对象的某个实例同时向另一类对象多个实例的通知
//if (colleagues.GroupBy(x => x.GetType()).Count() != colleagues.Count())
// throw new NotSupportedException();
foreach (var item in config)
{
var sources = colleagues.Where(x => x.GetType() == item.SourceType);
if ((sources == null) || (sources.Count() == 0))
continue;
var targets = colleagues.Where(x => x.GetType() == item.TargetType);
if ((targets == null) || (targets.Count() == 0))
continue;
var eventInfo = item.SourceType.GetEvent(item.SourceEventName);
if (eventInfo == null)
continue;
var methodInfo = item.TargetType.GetMethod(item.TargetHandlerMethodName, BindingFlags.Public | BindingFlags.Instance);
if (methodInfo == null)
continue;
// 绑定事件响应关系
foreach (var source in sources)
foreach (var target in targets)
eventInfo.AddEventHandler(source, Delegate.CreateDelegate(eventInfo.EventHandlerType, target, methodInfo));
}
return this;
}
}
实现和单元测试验证
using System;
using System.Diagnostics;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace MarvellousWorks.PracticalPattern.Mediator.Tests.Exercise
{
[TestClass]
public class DocumentWorkflowMediatorFixture
{
Scenario1.A a1;
Scenario1.B b1;
Scenario1.C c1;
Scenario2.A a2;
Scenario2.B b2;
Scenario2.C c2;
Scenario2.D d2;
EventMediatorBuilder scenario1Builder;
EventMediatorBuilder scenario2Builder;
/// <summary>
/// 配置不同协调关系
/// 实际项目中可以采用本章介绍的基于配置文件的定义方式
/// </summary>
[TestInitialize]
public void Initialize()
{
a1 = new Scenario1.A();
b1 = new Scenario1.B();
c1 = new Scenario1.C();
a2 = new Scenario2.A();
b2 = new Scenario2.B();
c2 = new Scenario2.C();
d2 = new Scenario2.D();
scenario1Builder = new EventMediatorBuilder()
// 1. A部门拟稿后将文件报B部门审核
.AddConfig(typeof(Scenario1.A), typeof(Scenario1.B), "WriteDocumentFinishedHandler", "OnReceiveFileToReview")
// 2. B部门对于文件审核后，确认文件体例没有缺项后就通知C部门发布
.AddConfig(typeof(Scenario1.B), typeof(Scenario1.C), "ReviewDocumentSucceedHandler", "OnReceiveFileToPublish")
// 3. 如果B部门发现文件体例有缺项时，将文件返回给A部门重新修改
.AddConfig(typeof(Scenario1.B), typeof(Scenario1.A), "ReviewDocumentFailedHandler", "OnReviewFailed")
// 4. C部门在接到B部门传来的文件时，先再发布，然后对其归档
.AddConfig(typeof(Scenario1.C), typeof(Scenario1.C), "DocumentPublishedHandler", "OnReceiveFileToArchive");
scenario2Builder = new EventMediatorBuilder()
.AddConfig(typeof(Scenario2.A), typeof(Scenario2.B), "WriteDocumentFinishedHandler", "OnReceiveFileToReview")
.AddConfig(typeof(Scenario2.A), typeof(Scenario2.D), "WriteDocumentFinishedHandler", "OnReceiveFileToArchive")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.A), "ReviewDocumentFailedHandler", "OnReviewFailed")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.D), "ReviewDocumentFailedHandler", "OnReceiveFileToArchive")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.C), "ReviewDocumentSucceedHandler", "OnReceiveFileToPublish")
.AddConfig(typeof(Scenario2.C), typeof(Scenario2.D), "DocumentPublishedHandler", "OnReceiveFileToArchive");
}
/// <summary>
/// 测试通过Event Mediator Builder构造现有业务流程下的协作关系
/// </summary>
[TestMethod]
public void TestScenario1()
{
// 通过Event Mediator以及配置信息建立三个部门Colleague间的协作关系
// 所有协调关系统一剥离到作为Mediator的.NET事件机制上
scenario1Builder.BuildAUpColleagues(a1, b1, c1);
// 成功的路径
Trace.WriteLine("Succeed path");
a1.Write("a", "b", "c");
// 失败的路径
Trace.WriteLine("\n\nFailed path");
a1.Write("a", "", "");
// 修正错误的内容，重新执行流程
Trace.WriteLine("Modified after review failed path");
a1.Write("a", "b", "c");
}
/// <summary>
/// 测试通过Event Mediator Builder构造管理层期望的未来业务流程下的协作关系
/// </summary>
[TestMethod]
public void TestScenario2()
{
// 通过Event Mediator以及配置信息建立三个部门Colleague间的协作关系
// 所有协调关系统一剥离到作为Mediator的.NET事件机制上
scenario2Builder.BuildAUpColleagues(a2, b2, c2, d2);
// 成功的路径
Trace.WriteLine("Succeed path");
a2.Write("a", "b", "c");
// 失败的路径
Trace.WriteLine("\n\nFailed path");
a2.Write("a", "", "");
// 修正错误的内容，重新执行流程
Trace.WriteLine("Modified after review failed path");
a2.Write("a", "b", "c");
}
}
}
using System.Diagnostics;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace MarvellousWorks.PracticalPattern.Mediator.Tests.Exercise
{
[TestClass]
public class DocumentWorkflowMediatorFixture
{
Scenario1.A a1;
Scenario1.B b1;
Scenario1.C c1;
Scenario2.A a2;
Scenario2.B b2;
Scenario2.C c2;
Scenario2.D d2;
EventMediatorBuilder scenario1Builder;
EventMediatorBuilder scenario2Builder;
/// <summary>
/// 配置不同协调关系
/// 实际项目中可以采用本章介绍的基于配置文件的定义方式
/// </summary>
[TestInitialize]
public void Initialize()
{
a1 = new Scenario1.A();
b1 = new Scenario1.B();
c1 = new Scenario1.C();
a2 = new Scenario2.A();
b2 = new Scenario2.B();
c2 = new Scenario2.C();
d2 = new Scenario2.D();
scenario1Builder = new EventMediatorBuilder()
// 1. A部门拟稿后将文件报B部门审核
.AddConfig(typeof(Scenario1.A), typeof(Scenario1.B), "WriteDocumentFinishedHandler", "OnReceiveFileToReview")
// 2. B部门对于文件审核后，确认文件体例没有缺项后就通知C部门发布
.AddConfig(typeof(Scenario1.B), typeof(Scenario1.C), "ReviewDocumentSucceedHandler", "OnReceiveFileToPublish")
// 3. 如果B部门发现文件体例有缺项时，将文件返回给A部门重新修改
.AddConfig(typeof(Scenario1.B), typeof(Scenario1.A), "ReviewDocumentFailedHandler", "OnReviewFailed")
// 4. C部门在接到B部门传来的文件时，先再发布，然后对其归档
.AddConfig(typeof(Scenario1.C), typeof(Scenario1.C), "DocumentPublishedHandler", "OnReceiveFileToArchive");
scenario2Builder = new EventMediatorBuilder()
.AddConfig(typeof(Scenario2.A), typeof(Scenario2.B), "WriteDocumentFinishedHandler", "OnReceiveFileToReview")
.AddConfig(typeof(Scenario2.A), typeof(Scenario2.D), "WriteDocumentFinishedHandler", "OnReceiveFileToArchive")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.A), "ReviewDocumentFailedHandler", "OnReviewFailed")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.D), "ReviewDocumentFailedHandler", "OnReceiveFileToArchive")
.AddConfig(typeof(Scenario2.B), typeof(Scenario2.C), "ReviewDocumentSucceedHandler", "OnReceiveFileToPublish")
.AddConfig(typeof(Scenario2.C), typeof(Scenario2.D), "DocumentPublishedHandler", "OnReceiveFileToArchive");
}
/// <summary>
/// 测试通过Event Mediator Builder构造现有业务流程下的协作关系
/// </summary>
[TestMethod]
public void TestScenario1()
{
// 通过Event Mediator以及配置信息建立三个部门Colleague间的协作关系
// 所有协调关系统一剥离到作为Mediator的.NET事件机制上
scenario1Builder.BuildAUpColleagues(a1, b1, c1);
// 成功的路径
Trace.WriteLine("Succeed path");
a1.Write("a", "b", "c");
// 失败的路径
Trace.WriteLine("\n\nFailed path");
a1.Write("a", "", "");
// 修正错误的内容，重新执行流程
Trace.WriteLine("Modified after review failed path");
a1.Write("a", "b", "c");
}
/// <summary>
/// 测试通过Event Mediator Builder构造管理层期望的未来业务流程下的协作关系
/// </summary>
[TestMethod]
public void TestScenario2()
{
// 通过Event Mediator以及配置信息建立三个部门Colleague间的协作关系
// 所有协调关系统一剥离到作为Mediator的.NET事件机制上
scenario2Builder.BuildAUpColleagues(a2, b2, c2, d2);
// 成功的路径
Trace.WriteLine("Succeed path");
a2.Write("a", "b", "c");
// 失败的路径
Trace.WriteLine("\n\nFailed path");
a2.Write("a", "", "");
// 修正错误的内容，重新执行流程
Trace.WriteLine("Modified after review failed path");
a2.Write("a", "b", "c");
}
}
}
备注1：现有情景下的A、B、C类型定义
namespace Scenario1
{
class A : Department
{
public event EventHandler<DocumentEventArgs> WriteDocumentFinishedHandler;
public void Write(string subject, string body, string comment)
{
if (Document == null) throw new NullReferenceException("Document");
Trace.WriteLine("A begin write");
Document.Subject = subject;
Document.Body = body;
Document.Comment = comment;
Trace.WriteLine("A write finished");
Trace.WriteLine(Document);
if(WriteDocumentFinishedHandler != null)
WriteDocumentFinishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReviewFailed(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("A received doc review failed from " + sender.GetType().Name);
Document = eventArgs.Document;
}
}
class B : Department
{
public event EventHandler<DocumentEventArgs> ReviewDocumentSucceedHandler;
public event EventHandler<DocumentEventArgs> ReviewDocumentFailedHandler;
public void Review()
{
Trace.WriteLine("B begin review");
var result =
(Document != null) &&
! string.IsNullOrEmpty(Document.Subject) &&
! string.IsNullOrEmpty(Document.Body);
if (result)
{
Trace.WriteLine("B review succeed");
if (ReviewDocumentSucceedHandler != null)
ReviewDocumentSucceedHandler(this, new DocumentEventArgs(Document));
}
else
{
Trace.WriteLine("B review failed");
if (ReviewDocumentFailedHandler != null)
ReviewDocumentFailedHandler(this, new DocumentEventArgs(Document));
}
}
public void OnReceiveFileToReview(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("B received doc from " + sender.GetType().Name + " to review");
Document = eventArgs.Document;
Review();
}
}
class C : Department
{
public event EventHandler<DocumentEventArgs> DocumentPublishedHandler;
public event EventHandler<DocumentEventArgs> DocumentArchivedHandler;
public void Publish()
{
Trace.WriteLine("C published ");
if(DocumentPublishedHandler != null)
DocumentPublishedHandler(this, new DocumentEventArgs(Document));
}
public void Archive()
{
Trace.WriteLine("C archived");
if(DocumentArchivedHandler != null)
DocumentArchivedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToPublish(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to publish from " + sender.GetType().Name);
Document = eventArgs.Document;
Publish();
}
public void OnReceiveFileToArchive(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to archive from " + sender.GetType().Name);
Document = eventArgs.Document;
Archive();
}
}
}
{
class A : Department
{
public event EventHandler<DocumentEventArgs> WriteDocumentFinishedHandler;
public void Write(string subject, string body, string comment)
{
if (Document == null) throw new NullReferenceException("Document");
Trace.WriteLine("A begin write");
Document.Subject = subject;
Document.Body = body;
Document.Comment = comment;
Trace.WriteLine("A write finished");
Trace.WriteLine(Document);
if(WriteDocumentFinishedHandler != null)
WriteDocumentFinishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReviewFailed(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("A received doc review failed from " + sender.GetType().Name);
Document = eventArgs.Document;
}
}
class B : Department
{
public event EventHandler<DocumentEventArgs> ReviewDocumentSucceedHandler;
public event EventHandler<DocumentEventArgs> ReviewDocumentFailedHandler;
public void Review()
{
Trace.WriteLine("B begin review");
var result =
(Document != null) &&
! string.IsNullOrEmpty(Document.Subject) &&
! string.IsNullOrEmpty(Document.Body);
if (result)
{
Trace.WriteLine("B review succeed");
if (ReviewDocumentSucceedHandler != null)
ReviewDocumentSucceedHandler(this, new DocumentEventArgs(Document));
}
else
{
Trace.WriteLine("B review failed");
if (ReviewDocumentFailedHandler != null)
ReviewDocumentFailedHandler(this, new DocumentEventArgs(Document));
}
}
public void OnReceiveFileToReview(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("B received doc from " + sender.GetType().Name + " to review");
Document = eventArgs.Document;
Review();
}
}
class C : Department
{
public event EventHandler<DocumentEventArgs> DocumentPublishedHandler;
public event EventHandler<DocumentEventArgs> DocumentArchivedHandler;
public void Publish()
{
Trace.WriteLine("C published ");
if(DocumentPublishedHandler != null)
DocumentPublishedHandler(this, new DocumentEventArgs(Document));
}
public void Archive()
{
Trace.WriteLine("C archived");
if(DocumentArchivedHandler != null)
DocumentArchivedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToPublish(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to publish from " + sender.GetType().Name);
Document = eventArgs.Document;
Publish();
}
public void OnReceiveFileToArchive(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to archive from " + sender.GetType().Name);
Document = eventArgs.Document;
Archive();
}
}
}
备注2：管理层期望的A、B、C、D类型定义
namespace Scenario2
{
class A : Department
{
public event EventHandler<DocumentEventArgs> WriteDocumentFinishedHandler;
public void Write(string subject, string body, string comment)
{
if (Document == null) throw new NullReferenceException("Document");
Trace.WriteLine("A begin write");
Document.Subject = subject;
Document.Body = body;
Document.Comment = comment;
Trace.WriteLine("A write finished");
Trace.WriteLine(Document);
if(WriteDocumentFinishedHandler != null)
WriteDocumentFinishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReviewFailed(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("A received doc review failed from " + sender.GetType().Name);
Document = eventArgs.Document;
}
}
class B : Department
{
public event EventHandler<DocumentEventArgs> ReviewDocumentSucceedHandler;
public event EventHandler<DocumentEventArgs> ReviewDocumentFailedHandler;
public void Review()
{
Trace.WriteLine("B begin review");
var result =
(Document != null) &&
! string.IsNullOrEmpty(Document.Subject) &&
! string.IsNullOrEmpty(Document.Body);
if (result)
{
Trace.WriteLine("B review succeed");
if (ReviewDocumentSucceedHandler != null)
ReviewDocumentSucceedHandler(this, new DocumentEventArgs(Document));
}
else
{
Trace.WriteLine("B review failed");
if (ReviewDocumentFailedHandler != null)
ReviewDocumentFailedHandler(this, new DocumentEventArgs(Document));
}
}
public void OnReceiveFileToReview(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("B received doc from " + sender.GetType().Name + " to review");
Document = eventArgs.Document;
Review();
}
}
class C : Department
{
public event EventHandler<DocumentEventArgs> DocumentPublishedHandler;
public void Publish()
{
Trace.WriteLine("C published ");
if(DocumentPublishedHandler != null)
DocumentPublishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToPublish(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to publish from " + sender.GetType().Name);
Document = eventArgs.Document;
Publish();
}
}
class D : Department
{
public event EventHandler<DocumentEventArgs> DocumentArchivedHandler;
public void Archive()
{
Trace.WriteLine("D archived");
if(DocumentArchivedHandler != null)
DocumentArchivedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToArchive(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to archive from " + sender.GetType().Name);
Document = eventArgs.Document;
Archive();
}
}
}
{
class A : Department
{
public event EventHandler<DocumentEventArgs> WriteDocumentFinishedHandler;
public void Write(string subject, string body, string comment)
{
if (Document == null) throw new NullReferenceException("Document");
Trace.WriteLine("A begin write");
Document.Subject = subject;
Document.Body = body;
Document.Comment = comment;
Trace.WriteLine("A write finished");
Trace.WriteLine(Document);
if(WriteDocumentFinishedHandler != null)
WriteDocumentFinishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReviewFailed(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("A received doc review failed from " + sender.GetType().Name);
Document = eventArgs.Document;
}
}
class B : Department
{
public event EventHandler<DocumentEventArgs> ReviewDocumentSucceedHandler;
public event EventHandler<DocumentEventArgs> ReviewDocumentFailedHandler;
public void Review()
{
Trace.WriteLine("B begin review");
var result =
(Document != null) &&
! string.IsNullOrEmpty(Document.Subject) &&
! string.IsNullOrEmpty(Document.Body);
if (result)
{
Trace.WriteLine("B review succeed");
if (ReviewDocumentSucceedHandler != null)
ReviewDocumentSucceedHandler(this, new DocumentEventArgs(Document));
}
else
{
Trace.WriteLine("B review failed");
if (ReviewDocumentFailedHandler != null)
ReviewDocumentFailedHandler(this, new DocumentEventArgs(Document));
}
}
public void OnReceiveFileToReview(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("B received doc from " + sender.GetType().Name + " to review");
Document = eventArgs.Document;
Review();
}
}
class C : Department
{
public event EventHandler<DocumentEventArgs> DocumentPublishedHandler;
public void Publish()
{
Trace.WriteLine("C published ");
if(DocumentPublishedHandler != null)
DocumentPublishedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToPublish(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to publish from " + sender.GetType().Name);
Document = eventArgs.Document;
Publish();
}
}
class D : Department
{
public event EventHandler<DocumentEventArgs> DocumentArchivedHandler;
public void Archive()
{
Trace.WriteLine("D archived");
if(DocumentArchivedHandler != null)
DocumentArchivedHandler(this, new DocumentEventArgs(Document));
}
public void OnReceiveFileToArchive(object sender, DocumentEventArgs eventArgs)
{
Trace.WriteLine("C received doc to archive from " + sender.GetType().Name);
Document = eventArgs.Document;
Archive();
}
}
}
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