JCO 2011 발표 자료용 - DSM 관련 내용 업데이트 - Code Metrics 관련 내용 업데이트

1. Framework EngineeringArchitecting, Designing, and Developing Reusable Libraries http://www.arload.net

2. 손영수 arload@live.com동완이 아빠, 인옥이 남편!!EVA팀 리더PLoP패턴 저자AsianPLoP공동의장Blog http://www.arload.net

3. Framework is ..

4. Framework is…

5. Douglas C. Schmidt Says.. Frameworks define “semi-complete” application that embody domain-specific object structures and functionality.

6. Libraries is.. Application Block DATABASE ADTs MATH NETWORKING App Specific Logic OO Design Invocations GRAPHICS GUI Event Loop Singleton Strategy Selections Reactor Adapter State Active Object Design Pattern Class Library Component Architecture

7. But Framework is .. Active Object State NETWORKING GUI Control – Flow (IoC) MATH Reactor Event Loop App Specific Logic Invocations Callbacks ADTs Singleton Adapter DATABASE GRAPHICS Application Framework Component Architecture

8. Why Do You Need Framework? Productivity Avoid Duplication

9. Why Do You Need Framework? De Facto War

10. Welcome to My Framework Journey!

11. Seed References “Framework Engineering”, TechED 2007 Europe “Framework Design Guidelines” , Addison Wesley Krzysztof Cwalina Program Manager on .NET Framework Team

12. 5 Topics.. D O P A V

13. OrganizationThe most powerful design tool O

14. Project Management Triangle Scope Time Cost O

15. Organization Project Management Triangle + 1 O

16. Do understand how organizational structure, culture, and decision making processes impact your product. O

17. Conway's law If you have 4 groups working on a compiler, you’ll get a 4-pass compiler. O

18. Conway's law O

19. Conway's Clean State Approach O

20. Your Company Culture Is .. Voluntary ?? O

21. Your Company Culture Is .. Familial ?? O

22. Remember Your Company Culture .. O Peremptory

23. Organizational InfluencesSize of Organization Simple Design Consistency Design Focus on 80/20 Rules Small Team O

24. Organizational InfluencesSize of Organization Powerful Design Lack Consistency Remove Requirements Large Team O

25. Organizational InfluencesOrganization’s Culture/Biases Customer-Focused End-2-End Scenarios O

26. Organizational InfluencesOrganization’s Culture/Biases Technology-Focused Long Lasting Architecture O

27. Decision Making Process is.. 呼兄呼弟 O

28. Solution ?? Give this book your boss..

29. Planning Ensuring we are building the right thing P

30. P

31. P

32. Skyscrapers Peanut Butter Focus: features Results: stability, incremental improvements, not great end-to-end scenarios Focus: scenarios Results: Excitement, breakthroughs, but beware of leaving existing customers behind P

33. Moderation (中庸)MileStone = Scenarios + Feature Vision statement RTM Feature complete Release Testing Planning M1 M2 Technology Preview Beta 1 Beta 2 RC1 P

34. ArchitectureEnsuring the long term health of the framework A

35. Right Way??Choose right types. A

36. Taxonomy of TypesLibraries , Primitives, Abstractions A

37. Primitives Very little policy (behavior design decisions) Stable design Commonly appear in publicly accessible APIs Almost impossible to evolve/change design; any design changes have huge breaking change impact on other APIs Example: Int32, String A

38. Libraries Definition: Libraries are types that are not passed between components Examples EventLog, Debug. Easy to Evolve Leave old in, add new one Beware of duplication! A

39. Abstractions Definition: Abstractions are interfaces or classes with unsealed members that are passed between components. Examples Stream, IComponent Hard to Evolve Unfortunately, pressure to evolve A

40. Primitive Oriented Design A.K.A. “Handle based design” (functional) Great evolvability, poor usability (sometimes) Low level stable primitives + high level reusable components with limited dependencies other than to the primitives E.g. Type.GetType(object) – works, but not as convenient as Object.GetType A

41. Extension Method for primitive.. C# 3.0 New Feature namespace MyCompany.StringManipulation { public static class StringExtensions{ public static bool IsNullOrEmpty(this string s){ return String.IsNullOrEmpty(s); } } } … using MyCompany.StringManipulation; string message= “hello world”; if(message.IsNullOrEmpty()){ Console.WriteLine(“EMPTY”); }

42. Component Oriented Design Rich APIs with lots of features, thus with lots of dependencies Great usability, poor evolvability Good for higher level components, not for the core of a platform A

43. Do Manage Dependencies.. A A

44. Component is .. Lego, Plug ?? A

45. Component is .. .. a set of types that ship and evolve as a unit. A

46. Types of Dependencies A

47. API Dependency Component A has an API dependency on component B, if a type in B shows in the publicly accessible API surface of a type in A. This includes: Base types and implemented interfaces Generic parameter constraints Return types and parameters of members Applied attributes Nested types A

48. Implemenatin Dependency If a type in A uses a type in B in its implementation. Hard Dependencies (required to run) Soft Dependencies (optional) A

49. Circular Dependency Component A depends on component B and Component B depends on component A (even indirectly). A

50. Solution is Layering.. A

51. Solution is Layering.. A

52. WPF XML    BCL Reflection A Dependency Management

53. 상황을 파악하는 좋은 방법DSM (Dependency Structure Matrix)

54. 간단한 DSM

55. 잘 계층화된 DSM

56. 엄격한 계층화를 유지한 시스템의 DSM

57. 불완전한 계층구조를 가진 시스템 Circular Dependency 발생.

58. 또 하나의 도구– Code Metrics

59. xDepend(Ndepend, Xdepend, CDepend) NDepend - http://www.xdepend.com

60. Solution is.. Create a new package. A

61. circular dependency GUI Comm Analysis Protocol Modem Control Comm Error Database Message Manager A

62. Indirect circular dependency A X B Y A

63. Use Interface. A X Y <<interface>> BY B A

64. Heavy Depedency.. A

65. Solution is IoC A

66. Heavy Dependency. // your API public class Tracer { MessageQueue mq = new MessageQueue(…); public void Trace(string message){ mq.Send(message); } } // your customer’s program that is hard to test Tracer tracer = new Tracer(); public void ProcessOrder(Order order){ tracer.Trace(order.Id); … } A

67. Inversion of Control // your better API public abstract class TraceListener { public abstract void Trace(string message); } public class Tracer { TraceListener listener; public Tracer(TraceListener listener){ this.listener = listener; } public void Trace(string message){ listener.Trace(message); } } A

68. Dependency Injection // your customer’s program that is easier to test Tracer tracer = new Tracer(new FileListener()); public void ProcessOrder(Order order){ tracer.Trace(order.Id); … } A

69. Dependency Injection Containers // customer’s program that is even easier to test Tracer tracer = container.Resolve<Tracer>(); public void ProcessOrder(Order order){ tracer.Trace(order.Id); … } Check outDI Containers (a.k.a. IoC Containers):autofac, Castle Windsor, PicoContainer.NET, Spring.NET, StructureMap, Unity, nInject and others. http://www.nInject.org A

70. Packaging Principle Package Cohesion Principle REP (Release Reuse Equivalency) CCP (Common Closure Principle) CRP (Common Reuse Principle) Package Coupling Principle ADP (Acyclic Dependencies Principle) SDP (Stable Dependencies Principle) SAP (Stable Abstraction Principle) A Robert C. Martin, Principle of Package Architecture http://www.objectmentor.com/resources/articles/Principles_and_Patterns.pdf

71. Do balance advances with compatibility. A

72. Types of “Compatibility” Backward Cross-Version Forward A

73. Cross-Redist. A

74. A

75. Establishing Compatibility Bar Define what’s a “breaking change” This definition depends on the objective E.g. Enable portable code between Silverlight and .NET Framework E.g. Enable cross-version portability? A

76. Avoid duplication and overlap. A

77. Team Space Show and Tell Problem Space PLoP – Capable, Productive and Satisfied Patterns for Productivity http://hillside.net/plop/plop98/final_submissions/P54.pdf A

78. When to Replace Existing APIs When the new technology is “10x better” Make sure you understand the impact on the ecosystem What would happen if the BCL team added a new String? What’s the migration path for code using the old API? Support Automatic Migration Tool. (VB -> VB.NET, .NET 1.0 -> .NET 2.0) Provide Code Based Migration Manual. COM+ -> WCF , ASP.NET Web Service -> WCF A

79. DesignThis is where quality happens D

80. Is using your framework correctly like… Running across a desert? D

81. You need Feedback. D

82. Do design APIs by first writing code samples for the main scenarios and then defining the object model to support the code samples. D

83. Code Samples D

84. Read File static void Main(string[] args) { StreamReadersr = File.OpenText("MyFile.txt"); string s = sr.ReadLine(); while (s != null) { s = sr.ReadLine(); Console.WriteLine(s); } } D

85. Feedback (Read File) static void Main(string[] args) { foreach (string s in File.ReadAllLines("MyFiles.text")) { Console.WriteLine(s); } } D

86. Object Model Listing D

87. Framework Design Studio Assembly Exploer Project -> Add -> Assembly D Download here - http://code.msdn.microsoft.com/fds

88. Framework Design Studio Assembly Review Comment D

89. Framework Design StudioCompare API Versions D

90. Framework Design StudioCompare API Versions Red is removed, Green is added, Grey means inherited. D

91. Framework Design StudioExporting to Microsoft Word Tools -> Export to Document D

92. Do treat simplicity as a feature. D

93. KISS (Keep It Simple! Stupid!) Remove Requirements (ATAM). Reuse Existing Concepts or APIs Adjust Abstraction Level Consider framework users(experience, knowledge) Three Example D

94. Domeasure, measure, and measure! D

95. Specification Document: Qualities Performance Goals (XML Parser..) Baseline: What do is the best my API could do? Measure delta from the baseline Threat Models (Security ..) Threat: What is the worst that my component could do? Mitigate the threats Keep a balance between many other qualities you want your framework to have (ATAM) D

96.  The POWER oFSameness D

97. Read the manual?? When you pick up your rental car…. Push the seat all the way back Find an NPR station Find the exit D

98. Oh, down to lock… D

99. How to use a key… D

100. Oh, you push the PRESS button… D

101. Who actually needs this data? D

102. Why you don’t read manuals ??? You know how to drive your car All cars work basically the same way Your rental car is a car Therefore, you can drive your rental car That is… The power of sameness D

103. Static Analysis Tool http://en.wikipedia.org/wiki/List_of_tools_for_static_code_analysis D

104. DevelopmentThe bits customers get, … or not V

105. Branches and Integrations- Feature Crew http://www.codeplex.com/BranchingGuidance/Wiki/View.aspx?title=Feature%20Crews%3a%20How%20Microsoft%20Does%20It V

106. Avoid integrating unfinished features. V

107. Feature Complete & Quality Gates Functional Specification Developer Design Specification Test Plan Threat Model API review Architectural Review Dependency Management Static Analysis Code Coverage Testing (Unit and Integration Tests) 0 Bugs Performance V

108. Do pay your debt. V

109. Milestone Quality Vision statement RTM Feature complete Release Testing Planning M1 M2 Technology Preview Beta 1 Beta 2 RC1 Milestone Quality V

110. Milestone Quality (MQ) Initiatives that are hard to do in regular milestones Large productivity and efficiency improvements Infrastructure changes For example, a new source control system Refactoring of fragile subsystems Internal implementation documentation Bugs backlog V

111. Summary Dounderstand how organizational structure, culture, and decision making processes impact your product. Avoidpeanut-butter in Scenario Based Application. Domanage your dependencies. Dobalance advances with compatibility. Avoidduplication and overlap. Do design APIs by first writing code samples for the main scenarios and then defining the object model to support the code samples. Do treat simplicity as a feature. Domeasure, measure, and measure! Avoidintegrating unfinished features. Do pay your debt.

112. Resources Krzysztof Cwalina, Brad Abrams Framework Design Guidelines: Conventions, Idioms, and Patterns for Reusable .NET Libraries http://channel9.msdn.com/pdc2008/PC58/ http://www.gotdotnet.com/team/fxcop

113. Resources Douglas C. Schmidt (PLoP Editor, POSA 2, 4 Writter) JAWS: An Application Framework for High Performance Web System http://citeseer.ist.psu.edu/81775.html (En) http://www.devpia.com/net2/EvaCast/Lecture/?cu=view&r=11 (Kr) Ralph Johnson (GoF , Design Patterns) Evolving Frameworks http://st-www.cs.uiuc.edu/users/droberts/evolve.html (En) http://arload.wordpress.com/2008/09/15/evolvingframeworks/ (Kr)

114. Resources Robert C. Martin Principles of Package Architecture (Design Principles and Design Patterns) http://www.objectmentor.com/resources/articles/Principles_and_Patterns.pdf (En) http://www.devpia.com/net2/EvaCast/Lecture/?cu=view&r=108 (Kr) For Korean People.. Load to Architect http://www.arload.net EvaCast (Online Free Lecture) http://www.evacast.net

115. 최근 저서 및 곧 나올 저서..

116. 곧 나올 저서..

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