Action Semantics for Model Transformation Systems

Recently, the main trends in software engineering have been dominated by the Model Driven Architecture (MDA) [1] vision of the Object Management Group (OMG). According to MDA, software development will be driven by a thorough modeling phase where (i) first a platform independent model (PIM) of the business logic is constructed from which (ii) platform specific models (PSMs) including details of the underlying software architecture are derived by model transformations (iii) followed by an automatic generation of the target application code. The PIMs and PSMs are defined by means of the Unified Modeling Language (UML), which has become the de facto standard visual object-oriented modeling language in systems engineering. Moreover, the recent inclusion of an action specification language to the UML standard (Action Semantics for UML [2]) seems to become a breakthrough for tool vendors to develop highly automated and optimized code generators for UML CASE tools. However, UML still lacks a precise formal semantics, which hinders the formal verification and validation of system design. Moreover, several shortcomings of the language have been revealed in domain specific applications as well. To provide formal semantics, UML models are typically projected into various mathematical domains (Petri nets, transition systems, process algebras, etc.), and the results of the formal analysis are back–annotated to the UML-based system model to hide the mathematics from designers [3].