A Concrete Syntax for UML 2.1 Action Semantics Using +CAL

Since UML 1.4 (the Unified Modeling Language, version 1.4), executable UML relies on the Precise Action Semantics for UML. The role of the action semantics is to provide the specification of actions. The UML has actions and activities, but no standard concrete syntax for describing them. Therefore, an action language is required to map higher- level constructs to the actions. This action language has to encompass both primitive actions and the control mechanisms provided by behaviors. In our paper, we present the advantages of adopting a more generic action language, in order to raise the level of abstraction. For the particular do- maine of Distributed Real-time Embedded (DRE) Systems, we have identified a need for formal verifications that leads us to implement a generic action language with formal features.