Representation of an elementary work situation
Introduction to the notion
A use case implies an interaction between an actor and the system. The definition given by the UML standard allows different interpretations. On the ground, modelers find it difficult to agree on the level of granularity of this notion.
The Praxeme definition helps to overcome this difficulty. It implicitly provides an identification criterion with the following practical consequences (the three unities):
- Only a single user participates in the run of a use case (one occurrence).
- This run-through of a use case is uninterruptible (excepting run-exceptions, error cases).
- The use case covers a precise user intention towards the system.