When it comes to Microsoft .NET-connected development, more and more frameworks are entering the market, both from Microsoft and from open source. Think of ASP.NET MVC, Castle, Windows Workflow Foundation (WF), Entity Framework, Unity, Linq2SQL, ADO.NET Data Services, Windows Communication Foundation (WCF), nHibernate, Spring.NET, CSLA, NUnit, Enterprise Library, MEF or ADF. Once you apply one or more frameworks to a project, the trouble begins. What if you require features that aren’t implemented in the framework? What if you decide that another framework would have been better and want to switch halfway through your project? What if the author of your favorite open source framework suddenly stops developing? What if the framework contains bugs or omissions? And what if a new version of the framework is released that is implemented differently? These and many more everyday problems can bring your project a halt, or at least require serious refactoring. During this highly interactive talk, Sander Hoogendoorn, chief architect of Capgemini’s agile Accelerated Delivery Platform and member of Microsoft’s Partner Advisory Council .NET, demonstrates pragmatic architectures and patterns that will help your projects avoid framework issues and to keep code independent of framework choices. Sander presents models of layered architectures, and looks at applying bridge patterns, managers-providers, dependency injection, descriptors and layer super-types, accompanied by lots of demos and (bad) code examples using blocks from Microsoft’s Enterprise Library, NHibernate, Log4Net, and the Entity Framework. Join this interactive discussion to share your experience of improving the structure and quality of your software architecture and code, and to discuss how to avoid common pitfalls of applying frameworks to .NET software development.

1. And patterns to help you avoid getting killed
Sander Hoogendoorn | Principal Technology Officer | Capgemini | @aahoogendoorn
ARC203 - HOW FRAMEWORKS CAN KILL YOUR PROJECTS

2. 2HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
Capgemini
Principal technology officer
Global agile thought leader
Chief architect Accelerated Delivery Platform (ADP)
Other
Microsoft Partner Advisory Council .NET
Author books and articles in international
magazines
Appreciated speaker at international conferences
Columns in several magazines
Editorial boards
Web
www.sanderhoogendoorn.com
www.smartusecase.com
Twitter: @aahoogendoorn
SANDER HOOGENDOORN

3. 3HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
ARC203 – How frameworks can kill your
projects
Tuesday 12:00
Hall 3.2 Interactive 2
ARC202 - How frameworks can kill your
projects
Wednesday 13:20
Hall 7.1b London 2
ARC203 – How frameworks can kill your
projects (repeat)
Thursday 10:30
Hall 3.2 Interactive 6
ARC205 – How smart use cases drive web
development
Friday 10:30
Hall 7.3 Berlin 1
SANDER HOOGENDOORN – TECHED 2010 SESSIONS

4. 4HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

5. 5HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

6. It always takes longer than you expect,
even when you take into account Hofstadter’s Law
HOFSTADTER’S LAW

7. 7HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MYFIRSTSURVEY

8. 8HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MYFIRSTSURVEY

9. Frameworks, like pizzas, come in only two sizes: too big and too small.
LIFE IS NEVER EASY …

10. 10HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MYFIRSTSURVEY

11. 11HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
WHAT’S IT GONNA BE PUNK?
General purpose frameworks
Enterprise Library, Spring.Net, Castle, NakedObjects,
Accelerated Delivery Framework (ADF), SubSonic
Single goaled frameworks – verticals
Dependency injection: ObjectBuilder, Unity, Castle
Windsor
Logging: Log4Net, Logging Block, Common.Logging
Exception handling: Exception Handling Block
Apect orientation: PostSharp, SetPoint
Search: Lucene.net, NLucene
Portals: DotNetNukeSpatial, Umbraco
Single goaled frameworks – architectural
User interface: Silverlight, ASP.NET MVC, WPF, ASP.NET
Ajax, Spring MVC
Process: UI Process Application Block, WF
Domain: Entity Framework, Hibernate, NEO
Data: Entity Framework, Hibernate, Castle ActiveRecord,
CSLA
Service s: WCF, WCF RIA

12. 12HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
FRAMEWORKS - CODEPLEX

13. 13HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
FRAMEWORKS – WWW.CSHARPOPENSOURCE.COM

14. 14HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
FRAMEWORKS – MICROSOFT ENTERPRISE LIBRARY

15. 15HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
FRAMEWORKS – PROJECT CASTLE

16. 16HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DON’T BELIEVE THE HYPE – IT’S A SQL

17. 17HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CONVINCING THE MANAGEMENT TO APPLY THE FRAMEWORK (25.5 %)

18. 18HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
UNDERSTANDING THE FRAMEWORK (56.4 %)

19. 19HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CONVINCING OTHER DEVELOPERS TO USE THE FRAMEWORK (23.6 %)

20. 20HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
TRAINING THE DEVELOPERS (20 %)

21. 21HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
THE EYE OF THE TIGER

22. 22HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

23. My software never has bugs. It just develops random features
APPLYING FRAMEWORKS

24. 24HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
SO GLAD YOU MADE IT!
What if we require
additional features that
aren’t covered by our
framework?
What if we decide that
another framework might
be better than the one
we’re using now?
What if the author of our
favorite framework suddenly
stops developing it?
What if the framework
contains bugs?
And what if the new version
of our framework is
implemented totally
different?

25. 25HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MORE THAN ANYTHING, DEPENDENCIES WILL KILL YOUR PROJECT

26. A short story about framework developers and application developers
KENTUCKY FRIED ARCHITECTURE

27. 27HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
THE CUSTOMER IS NOT ALWAYS RIGHT

28. 28HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
PIGS & CHICKENS
The application
developer
The framework
developer

29. 29HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
KFC ARCHITECTURE – ENTITY FRAMEWORK

30. 30HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
KFC ARCHITECTURE – ENTITY FRAMEWORK

31. 31HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
KFC ARCHITECTURE – ENTITY FRAMEWORK

32. I don’t care if it works on your machine! We are not shipping your machine!
LETTING THE LUNATICS RUN THE ASYLUM
Here’s … beta!

33. 33HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
ON THE WRONG TRACK

34. 34HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
HOT OR NOT?
Hot? From hot to not? Not?
HTML5
LightSwitch
WCF RIA Services
Silverlight 4.0
ASP.NET MVC 2 (3?)
ASP.NET Dynamic Data
ADO.NET Data Services
MEF
Azure Services
jQuery
NService Bus
Oslo
M
MGrammar
Expression Blend
ASP.NET Ajax
REST
Dublin
BizTalk
Surface
Duet
SketchFlow
Entity Framework 2.0
LINQ2SQL
LINQ2Entities
Entity Data Model
WPF
Unity
DSL’s
Silverlight 2.0
F#
ASP.NET
PopFly

35. 35HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
HERE’S JOHNNY! – ASP.NET MVC

36. 36HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
HERE’S JOHNNY! – ASP.NET MVC

37. It’s only in theory that practice and theory are the same
NO STRINGS ATTACHED

38. 38HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MYFIRSTSURVEY

39. 39HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CHANGING BASE CLASSES – – NHIBERNATE / LOG4NET

40. 40HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CHANGING BASE CLASSES – NHIBERNATE / LOG4NET

41. Programming is like sex.
One mistake and you have to support it for the rest of your life
YES, YOUR FRAMEWORKS VERSION TOO

42. 42HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
IT AIN’T OVER TILL IT’S OVER

43. 43HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MISSING BASE CLASSES – WORKFLOW FOUNDATION 4.0

44. 44HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MISSING BASE CLASSES – WORKFLOW FOUNDATION 4.0

45. HOW TO AVOID GETTING KILLED

46. 46HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

47. Architecture starts when you carefully put two bricks together. There it begins.
SOUND ARCHITECTURE

48. (SOFTWARE.ARCHITECTURE != LIST<FRAMEWORK>)

49. 49HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
A SOFTWARE ARCHITECTURE

50. 50HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
Presentation
Process
Domain
Data / Services
Outside world
Pages
UserControls
Panels
Use cases
Workflow
Domain objects / Entities
Factories / Repositories
Enums / Value objects / Smart references
[Mapping]
Service gateways
Service locators
[Mapping]
Databases
Services / ESB
Exact SAP BizTalk Java
Silverlight
XAML
Entities
(from EF)
Domain
Services
Metadata
Entity Framework
LINQ
Nhibernate?
MVVM?
MVP?

51. 51HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
THE GOOD, THE BAD AND THE UGLY
Dependencies
Using frameworks is simply good, gringo
However, being dependant on third parties
can put your project at risk
How stable are the frameworks you use?
How stable is the framework vendor?
Minimize dependencies
Map frameworks to your software architecture,
not vice versa
Define your own layer supertypes
Wrap framework functionality
Apply manager-provider pattern
Implement extension methods if all fails

52. 52HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

53. From a programmer's point of view the user is a peripheral
that types when you issue a read request.
LAYER SUPERTYPE

54. 54HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE What’s a layer supertype Ollie?
Acts as a supertype for all types in
its layer
All types inherit from the layer
supertype
Well Stan, it’s characteristics are
Name expresses common behaviour
Forces common features on all inherited types
Ideal starting point for services
Initially the layer supertype is empty
Reserve layer supertype for future additions
Extension methods don’t (always) help, you know

55. 55HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE – ASP.NET MVC

56. 56HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE – ASP.NET MVC

57. 57HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
Presentation
Process
Domain
Data / Services
Outside world
Pages
UserControls
Panels
Use cases
Workflow
Domain objects / Entities
Factories / Repositories
Enums / Value objects / Smart references
[Mapping]
Service gateways
Service locators
[Mapping]
Databases
Services / ESB
Exact SAP BizTalk Java

58. 58HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE – USING A LAYER SUPERTYPE

59. 59HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE – DEFINE SERVICES ON LAYER SUPERTYPES

60. 60HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
LAYER SUPERTYPE – EXTENSION METHODS ON LAYER SUPERTYPES

61. 61HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

62. Always code as if the guy who ends up maintaining your code
will be a violent psychopath who knows where you live.
DESCRIPTOR

63. 63HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
I KNOW NOTHING. I’M FROM BARCELONA
What is the matter
Mister Fawlty?
The problem Manual, is that
I want to use constants in my
application
But I want to define them in my
framework and extend them in my
application
Enumeration won’t do – there’s no
inheritance

64. 64HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR – THE PROBLEM (1)

65. 65HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR – THE PROBLEM (2)

66. 66HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
ENUM?

67. 67HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
STRING COLLECTION?

68. 68HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
STRING COLLECTION

69. 69HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
I KNOW NOTHING. I’M FROM BARCELONA
Descriptor
Defines a restricted but
application specific
extendible list of
definitions
Useful when
Enums can not be inherited
Framework defines enumeration
types that need to be extended in
application code
Define layer supertype using
reflection
Pre-define frequently used instances

70. 70HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN

71. 71HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN - DEFINITION

72. 72HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN – EXTENDED DEFINITION

73. 73HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN – USE IN FRAMEWORK

74. 74HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN – USE IN APPLICATION

75. 75HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MYFIRSTSURVEY

76. 76HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN – USE IN ASP.NET MVC

77. 77HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DESCRIPTOR PATTERN – USE IN ASP.NET MVC

78. 78HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
AGENDA
An short story
about frameworks
How frameworks can
get you in trouble
Software architecture
versus frameworks
The layer
supertype
Introducing the
descriptor pattern
The
manager-provider

79. XML is like violence.
If it doesn’t solve your problems, you are not using enough of it.
DEPENDENCY INJECTION

80. 80HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
A NEW DISEASE?
What do you think it is?
Create true separation between
definition and implementation, so
that the two can vary independently
and can be replaced easily
Looks like a typical case of dependency
injection to me
Call functionality without having to know
the actual implementation
Implement replaceable services
Apply implementations in different contexts
Plug-in services at run-time
So …
Single topic services
Single or multiple implemenations
need to be handled, which differs
dependant on context, like with
Windows API, logging or error
handling
Unit testing

81. 81HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DIFFERENT VARIATIONS? Did you know that there
are different types of this
dependency injection?
Arggh…
Yeah, sure. There’s
Constructor injection
Property (setter) injection
And even manual injection
Who cares doc?

82. 82HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DEPENDENCY INJECTION – CONSTRUCTOR INJECTION

83. 83HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DEPENDENCY INJECTION – MANUAL INJECTION
c

84. 84HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
DEPENDENCY INJECTION – WHAT TO PLUG IN
Yes, XML will hurt you too!

85. "Teamwork is a lot of people doing what I say“
Marketing executive, Citrix Corporation
MANAGER – PROVIDER

86. 86HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
Definition
Create a simple static facade (manager) for
a (set of) interfaced implementations
(providers)
In practice
Manager holds one or a collection of
providers
Provider implement a particular interface
Manager has methods to call methods
from interface
At run-time, using dependency injection,
actual providers are injected
MANAGER-PROVIDER PATTERN

87. 87HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MANAGER – VALIDATIONMANAGER

88. 88HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
INTERFACE

89. 89HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MANAGER – INITIALIZATION (USING DEPENDENCY INJECTION)

90. 90HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CONFIGURATION OF IMPLEMENTATION

91. 91HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
MANAGER - EXECUTING METHODS

92. 92HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
CLIENT – CALLING METHODS

93. 93HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
Useful when
Generic services need to be called, which may have
different implementations
Manager prevents having to loop through each of a
list of providers
Flexibility to add or remove providers without
changing application code
Providers differ e.g. in development code, test code
or deployed code
Use for
Task Management
View Management
Binding and Persisting
Resource Management
State Management
Logging
Datasource interaction
Testing!
MANAGER-PROVIDER PATTERN

94. 94HOW FRAMEWORKS CAN KILL YOUR PROJECTS
©2010 Capgemini. All Rights Reserved
THE GOOD, THE BAD AND THE UGLY
Dependencies
Using frameworks is simply good, gringo
However, being dependant on third parties
can put your project at risk
How stable are the frameworks you use?
How stable is the framework vendor?
Minimize dependencies
Map frameworks to your software architecture,
not vice versa
Define your own layer supertypes
Wrap framework functionality
Apply manager-provider pattern
Implement extension methods if all fails

95. www.accelerateddeliveryplatform.com
WWW.SMARTUSECASE.COM

96. sander.hoogendoorn@capgemini.com
www.sanderhoogendoorn.com | www.smartusecase.com
Twitter: @aahoogendoorn
REFERENCES AND QUESTIONS