Lambers, LeenJurack, StefanMehner, KatharinaRunge, OlgaTaentzer, Gabriele2020-06-172020-06-1720081436-9915https://depositonce.tu-berlin.de/handle/11303/11399http://dx.doi.org/10.14279/depositonce-10283In use case-driven approaches to requirements modeling, UML activity diagrams are a wide-spread means for refining the functional view of use cases. Early consistency validation of activity diagrams is therefore desirable but difficult due to the semi-formal nature of activity diagrams. In this paper, we specify well-structured activity diagrams and define activities more precisely by pre- and post- conditions. They can be modeled by interrelated pairs of object diagrams based on a domain class diagram. This activity refinement is based on the theory of graph transformation and paves the ground for a consistency analysis of the required system behavior. A formal semantics for activity diagrams refined by pre- and post-conditions allows us to establish sufficient criteria for consistency. The semi-automatic checking of these criteria is supported by a tool for graph transformation.en004 Datenverarbeitung; Informatikclass diagramgraph transformationactivity blockactivity diagramtype graphResearch Paper