Checkpoints: Use-Case Model

• The Introduction section of the use-case model provides a clear, concise overview of the purpose and functionality of the system.

• The use case model clearly presents the behavior of the system; it is easy to understand what the system does by reviewing the model.

  • No long chains of include and extend relationships, such as when an included use case is extended, or when an extended use case includes other use cases.  These can obscure comprehensibility.
  • Minimal cross-dependencies where an included, extending, or specialized use case must know about the structure and content of other included, extending or specialized use cases.

• All use cases have been identified; the use cases collectively account for all required behavior.

• All functional requirements are mapped to at least one use case.

• All non-functional requirements that must be satisfied by specific use cases have been mapped to those use cases.

• The use-case model contains no superfluous behavior; all use cases can be justified by tracing  them back to a functional requirement.

• All relationships between use cases are required (i.e. there is justification for all  include-, extend-, and generalization-relationships).

• Where the model is large and/or the responsibilities for parts of the model are distributed, use case packages have been appropriately used.

  • Cross-package dependencies have been reduced or eliminated to prevent model element ownership conflicts.
  • Packaging is intuitive and makes the model easier to understand.