Semantics-Based Weaving of UML Sequence Diagrams

In this paper we briefly introduce an aspect language that can define cross-cutting effects on a set of UML 2.0 sequence diagrams. Our main contribution is to weave aspects and sequence diagrams at the model level. By basing the weaving upon a formal trace model for sequence diagrams, we ensure that the weaving is semantics-based. To avoid the intractability of working on complete trace sets, we define a lifeline-based weaving upon trace-based equivalence classes. A major challenge is to handle unbounded loops which produce infinite trace sets. We establish a systematic way to rewrite the original loop definition so that the weaving can be performed on a finite structure. A weaving tool has been implemented to validate the approach.