Analysis

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Analysis
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Why analysis?

• Yield a more precise specification of the
  requirements.
• Introduce formalism and reasoning about the
  internal system using the developers language
• Structure the requirements in a way to be ready
  for design and implementation.
• First cut at a design model.

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Analysis Class

• Fig 8.4
• An analysis class represents an abstraction of
  one or several classes and or subsystems in the
  systems design
• Characteristics
• Focus on handling functional requirements
  (conceptual)
• Define behavior as responsibility, not operations
  
• Define conceptual attributes from problem domain
• Define conceptual relationships

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Boundary classes

• Responsibility
• Model interaction between the system and its
  actors
• Model the parts of the system that depend on its
  actors
• Clarify and collect the requirements on the
  systems boundaries
• Isolate user interfaces with the systems
  internal structure
• Boundary classes represent abstractions of visual
  interface components
• Each boundary class should be related to at least
  one actor

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Entity classes

• Responsibility
• Model information that is long-lived and often
  persistent
• Model information and associated behavior of some
  phenomenon or concept (e.g. individual, real-life
  object, real-life event)
• Show logical data structure and contribute to the
  understanding of what information the system
  dependent upon.
• Usually derived from business entities from
  business model
• An entity object encapsulates its persistent data
  as attributes and behaviors or operations to
  manipulate the data.

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Control classes

• Responsibility
• Model dynamics of the system, including
  coordination, sequencing, transactions and
  control of other objects
• Encapsulate control related to a use case
• Represent business logic, complex derivation and
  calculations
• A control object coordinates the main actions and
  control flow of a use case, and delegate work to
  other (boundary, entity, as well as control)
  objects

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Artifact Use-case Realization Analysis

• What is a use-case realization analysis?
• A collaboration within the analysis model
• It describes how a specific use case is realized
  and performed in terms of analysis classes and
  their interacting analysis objects
• It provides a straightforward trace to a specific
  use case in the use-case model
• consists of
• Class diagrams
• Interaction diagrams
• Flow of events - analysis

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• Class diagrams
• For each use-case realization, show participating
  analysis classes and their collaboration through
  their relationships
• Interaction diagrams (collaboration diagrams)
• Collaboration diagrams are used to describe how
  typical scenarios or use-case instances are
  realized with collaborations of objects from the
  participating analysis classes.
• Flow of events analysis
• Rewrite in text the flow of events from the
  use-case model for each use-case realization
  using in terms of collaboration of analysis
  objects.
• No reference to objects attributes,
  responsibilities, and associations.