Chapter 13: Capturing Framework Requirements

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Chapter 13 Capturing Framework Requirements

• Bonnie Hou
• 3/30/2000

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Road Show

• Background
• Framework Requirements
• Requirement Lvl
• Use-case Assortment
• Create a Business Case
• Large Use-Case Model
• Related Works
• Summary
• (abbr. FW-Framework, UC-Use Case)

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Background

• Experiences in a broad spectrum of domains by
  authors
• Formal method developed over yrs of experiences
• Domain analysis domain knowledge and think
  abstractly
• UC modeling
• Solid process

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FW Requirements

• FW Development two approaches
• Refactoring Approach
• Priori Approach
• Reenskaugs 4 generalized FW conditions
• There must be multiple elements with common
  characteristics
• Requirement for FW must be well understood
• Sufficient business justification must exist for
  FW
• Pattern must be abstracted

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FW Requirements- Requirement Lvl

• Hierarchical classification of requirements
• Business / Application / Design
• Corresponding Lvl of Requirements, UC and FW (?)

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FW Requirements UC Assortment

• A technique supporting the capture of domain
  info. during UC modeling, which is then used for
  FW development in priori approach.
• A step btwn requirement analysis and analysis
  modeling.
• (contd)

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FW Requirements UC Assortment (cond)

• Technique Abstraction (Pattern figured out)
• Heuristics
• 1. UCs that represent common behavior, but that
  do not share a primary actor, maybe grouped by
  creating an abstract actor
• 2. Each ensemble UC must follow all of the
  behavior defined in the FW UC, although the
  ensemble UC may determine how it will follow that
  behavior
• (cond)

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FW Requirements UC Assortment (cond)

• Heuristics
• 3. When two UCs have an extends relationship with
  the same higher-lvl UC, their primary actors
  should be specializations of the abstract primary
  actor associated with the higher-lvl UC
• 4. UCs that describe action on a common domain
  object should be grouped under a common actor.
• (cond)

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FW Requirements UC Assortment (cond)

• Examples UC Modeling and

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FW Requirements UC Assortment (cond)

• UC Assortment
• Find abstract actors
• Identify abstract UC through grouping
• Describe abstract UC
• (depending on domain knowledge and abstract
  thinking / help of heuristics)
• More successful as size grows

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FW Requirements Create a Business Case

• Make to justify amount of effort/money
• Could be made on variety of lvls
• Easier with well defined UC model
• Helpful in risk control, but not necessary
• A field for future research

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FW Requirement- Large UC Model

• Increase in functionality and size could provide
  more opportunities to factor out commonality
• Change cases included to capture near-future
  changes
• Attention Use Case Explosion
• Too much details
• Too much change cases
• (Thought there is always tradeoff.)

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Related Works

• Gause and Weinberg
• grouping requirement attributes
• Taligent
• view domain expertise as the focus
• Jacobson, Griss and Jonsson
• utilize use case to identify component systems
  using feedback fm application engineers
• Koskimies and Mossenbock
• two-phases (generalization of problem and
  implementation)

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Summary

• Isomorphism of 3 Lvls of UC and FW
• UC assortment to capture FW requirements in a
  priori approach

Building Application Framework, pp320