On the refinement of use case models with variability support

Modeling software product lines shall imply modeling from different perspectives with different modeling artifacts such as use case diagrams, component diagrams, class diagrams, activity diagrams, sequence diagrams and others. In this paper, we elaborate on use cases for modeling product lines and we explore them from the perspective of variability by working with the unified modeling language (UML) ?extend? relationship. We also explore them from the perspective of detail by (functionally) refining use cases with ?extend? relationships between them. This paper’s intent is to provide for comprehension about use case modeling with functional refinement when variability is present.