Domain Engineering

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Domain Engineering

• Arie van Deursen
• May 2001

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Software Product Line
SAP, Baan, PeopleSoft

• Group of products
• sharing a common, managed set of features
• to satisfy the needs of a selected market
• Examples
• Telephone switches 5ESS
• Mortgage / insurance portals
• Customer Relation Management
• On line banking

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Object-OrientedApplication Framework

• Framework
• Set of cooperating classes embodying an abstract
  design
• For solutions to a family of related problems
• Supporting reuse beyond the class level.
• Building an appliction consists of adding class
  specializations
• Inverse control

4
Product Line Savings

• Economies of scale
• Savings from using technology to
• produce a greater volume of a single output
• with the same or less inputs
• Economies of scope
• Savings from using technology to
• build a greater diversity of outputs
• with the same or less inputs

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Domain / ApplicationEngineering

• Domain engineering
• Systematic approach to construct reusable assets
  in a given problem domain
• Application engineering
• Use the assets to build specialized software
  systems in the given domain.
• ( Product / customer development )

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What is a Domain?

• Domain as the real world
• Adopted in OO / AI community
• Domain as a set of systems
• Systematic software reuse community
• Domain criteria
• Mature, stable, economically viable
• Use legacy systems to understand domain.

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Domain Engineering

• Activity of
• collecting, organizing and storing past
  experience in building (parts of) systems
• in a particular domain
• in the form of reusable assets
• as well as providing means for resuing these
  assets (retrieve, adapt, assemble, ...)
• when building new systems

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ODM Organization Domain Modeling

• 1. Plan Domain
• Set objectives, analyze stakeholders
• Scope domain selection criteria
• Define domain boundary conditions, examples,
  counter examples, main features,
• relations to other domains.

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ODM (2)

• 2. Model Domain
• Acquire domain information experts, legacy
  systems, literature, prototyping, ...
• Describe domain lexicon of terms, commonality
  variability feature diagrams
• Refine domain build overall domain, analyze
  trade offs, innovative feature combinations

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ODM (3)

• 3. Engineer Asset Base
• Scope correlate features and customers,
  prioritize, select.
• Architect external and internal constraints,
  components, domain-specific languages,
  generators, framework, ...
• Implement OO, code generation, ...

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Car Feature Diagram
Car
Car body
Engine
Pulls trailer
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Car Class Diagram
CarBody
Cartransmission
Trailer
O..1
O..1
ElectricGasolineCar transmission
ElectricCar transmission
GasolineCar transmission
ElectricEngine
GasolineEngine
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Feature Diagrams
Car
Engine
Pulls trailer

• Node types
• Mandatory / Optional
• Alternatives / Or-features
• Diagram generates instances
• Commonality feature in all instances
• Variation point optional, alternative, or.
• Find variation dependencies.
• No implementation bias

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Imperative Lists
List
Length Counter
Tracing
Ownership
Morphology
Mono morphic
Poly morphic
External Reference
Owned Reference
Copy
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Interest Rate Products
Product
Swap
Deposit
Fixed Deposit
Floating Deposit
Interest Amount
Principle Amount
Period
Convention
Rate
Start Date
Maturity Date
Currency
Simple, Dutch, 360, ...
DEM, USD, EUR, ...
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Finding Features

• Use feature starter sets
• Record similarities between instances
• Record differences between instances
• Organize features into hierarchies
• Analyze feature combinations
• Record additional feature information
• Identify more features than needed

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Generative Programming

• A software engineering paradigm in which
• given a particular requirements specification
• a highly customized and optimized intermediate or
  end-product
• can be automatically manufactured on demand
• from elementary, reusable implementation
  components
• by means of configuration knowledge

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Domain-SpecificLanguages

• Expressive over variable features
• Composition, defaults, dependencies, pragmas,
  illegal combinations
• Common features built-in / in compiler.
• Expression DSL
• Domain-specific computations
• Configuration DSL
• Specify a concrete program family member

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Further Reading

• ODM Guide Book
• Generative programming chapter 2 4, and
  examples in chs 12, 13, 14.
• From the Transform Wiki
• Annotated Bibliography
• Little Languages Little Maintenance?
• Draco transformation system and domain
  engineering methodology.

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Summary

• Domain engineering
• Product Line
• Economy of Scope
• Domain
• ODM
• Variability
• Commonality

• Feature Diagrams
• Class Diagrams
• Generative Programming
• Domain Specific Languages

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Project

• Tool support for feature diagrams
• Design language
• apply to simple examples
• analyze consequences of realistic examples
• Implement normalizations
• Generate pictures
• Suggest class diagram options