Mar 2, 2007 ... What are the drivers and tradeoffs? • What technologies to select? • Fowler:
Patterns of Enterprise Application Architecture, Addison. Wesley ...
Enterprise Application Patterns
Ingolf H. Krueger
Department of Computer Science & Engineering University of California, San Diego La Jolla, CA 92093-0404, USA
California Institute for Telecommunications and Information Technologies La Jolla, CA 92093-0405, USA
Typical Business Information System
Client Devices
Presentation & Content
Appliances
Client Tier
Web Server
Presentation Tier
App Server Business Processing
Data Management
Business Tier
Info Server
Information Tier adapted from [M05]
March 2, 2007
© Ingolf H. Krueger
CSE
2
Enterprise Application Patterns • How to build and integrate layers: – Client (access devices) – Presentation (handling of client requests) – Domain (application logic) – Data (databases, other data sources)
• What alternative approaches exist? • What are the drivers and tradeoffs? • What technologies to select? • Fowler: Patterns of Enterprise Application Architecture, Addison Wesley, 2003
March 2, 2007
© Ingolf H. Krueger
CSE
3
Enterprise Application Patterns
Domain Logic: • • • •
Transaction Script Domain Model Table Module Service Layer
adapted from [F03] March 2, 2007
© Ingolf H. Krueger
CSE
4
Example: Domain Model
Data Mapper
Data Store
Selection Made
Init
Add to Cart
Checkout
Application Server
March 2, 2007
© Ingolf H. Krueger
CSE
5
Enterprise Application Patterns
Presentation:
adapted from [F03] March 2, 2007
• • • • •
MVC Page/Front Controller Template/Two Step View Application Controller …
© Ingolf H. Krueger
CSE
6
Example: Page Controller
• handle HTTP get/post • select model/view
servlet JSP
Selection Made
Init
display HTTP
Add to Cart
Checkout
Application Server adapted from [F03] March 2, 2007
© Ingolf H. Krueger
CSE
7
Enterprise Application Patterns adapted from [F03]
Data Access: • • • • • •
Table/Row Data Gateway Active Record Data Mapper Unit of Work Identity Map Lazy Load March 2, 2007
• • • • • •
Identity Field Foreign Key Mapping Association Table Mapping Dependent Mapping Embedded Value Lazy Load © Ingolf H. Krueger
• Serialized LOP • Single/ Class/ Concrete Table Inheritance • Inheritance Mappers CSE
8
Enterprise Application Patterns
Data Access: • Metadata Mapping • Query Object • Repository adapted from [F03] March 2, 2007
© Ingolf H. Krueger
CSE
9
Example: Data Mapper
Data Store
Application Server
Data Mapper adapted from [F03]
March 2, 2007
© Ingolf H. Krueger
CSE
10
Enterprise Application Patterns adapted from [F03]
Distribution, Concurrency, State: • Remote Facade • Data Transfer Object
• Optimistic/Pessimistic Offline Lock • Coarse Grained/Implicit Lock
• Client/Server/Database Session State March 2, 2007
© Ingolf H. Krueger
CSE
11
Enterprise Application Patterns adapted from [F03]
Base: • • • •
Gateway Mapper Layer Supertype Separated Interface
March 2, 2007
• • • •
Registry Value Object Money Special Case
© Ingolf H. Krueger
• Plugin • Service Stub • Record Set
CSE
12
Configuration Example: Simple Application
Transaction Script MVC with Two Step View or Application Controller
March 2, 2007
© Ingolf H. Krueger
Table Data Gateway
CSE
13
Configuration Example: Complex Application
Domain Model Service Layer MVC Data Mapper Metadata Mapper
March 2, 2007
© Ingolf H. Krueger
CSE
14
Archetype Example: Person (partial) adapted from [AN03]
March 2, 2007
© Ingolf H. Krueger
CSE
15
Archetype Example: PartyRole (partial) adapted from [AN03]
March 2, 2007
© Ingolf H. Krueger
CSE
16
Archetype Example: ProductCatalog (partial) ProductCatalog
adapted from [AN03]
1 0..* CatalogEntry
0..* 1..* 1
1..*
1
mandatory
ProductType
ProductIdentifier
0..*
1..*
optional 0..*
ProductFeature Type
1
0..* SerialNumber
March 2, 2007
1 0..1
ProductInstance
ProductFeatureInstance
1 © Ingolf H. Krueger
1..* CSE
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Example: Party – Role – Relationship – Policy Model* * courtesy of Matthew Arrott; adapted from [AN03]
March 2, 2007
© Ingolf H. Krueger
CSE
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