Automated composition of sequence diagrams via Alloy

Design of large systems often involves the creation of models that describe partial specifications. Model composition is the process of combining partial models to create a single coherent model. This paper presents an automatic composition technique for creating a sequence diagram from partial specifications captured in multiple sequence diagrams with the help of Alloy. Our contribution is twofold: a novel true-concurrent semantics for sequence diagram composition, and a model-driven transformation of sequence diagrams onto Alloy that preserves the semantics of composition defined. We have created a tool called SD2Alloy that implements the automated technique and works as follows: two given sequence diagrams are transformed in two Alloy models, and then combined according to a set of logical constraints, determined by our compositional semantics, into a final composed Alloy model. The technique can also be used to detect problems and inconsistencies in the composition of diagrams.