Why do we need use cases?
Use cases allow to describe even a complex system in an easy to understand way, and tell in simple terms what the system is going to do for its users. The most difficult aspect of developing a system is the precise conceptualisation and specification of the system to be built. Use cases help establish and communicate requirements of a system in a simple manner.
Use Cases (Formal Definition):
“A description of a set of sequences of actions, including variants, that a system performs that yield an observable result of value to an actor.”
[Rumbaugh, James, Ivar Jacobson, and Grady Booch. “The unified modeling language reference manual.” (1999).]
A use case can be developed as a use case narrative and/or represented diagrammatically using use case diagrams.
Elements of good choice cheap online viagra a use case:
- Actor: An entity that interacts with the system fot the only now purpose of completing an event.
- Functional requirement: Use cases capture functional requirements that specify the intended behaviour of the system.
- Goals: Use cases are typically initiated by a user to fulfil goals describing the activities and variants involved in attaining the goal.
2. Online Resources
Use case specification: http://epf.eclipse.org/wikis/openup/core.tech.common.extend_supp/guidances/examples/use_case_spec_CD5DD9B1.html
More formal introduction to use cases: http://www.uio.no/studier/emner/matnat/ifi/INF5120/v04/undervisningsmateriale/UseCases.pdf