Coping with Semantic Variation Points in Domain-Specific Modeling Languages

International audienceEven if they exhibit differences, many Domain-Specific Modeling Languages (DSMLs) share elements from their concepts, notations and semantics. StateCharts is a well known family of DSMLs that share many concepts but exhibit notational differences and many execution semantics variants (called Semantic Variation Points – SVPs –). For instance, when two conflicting transitions in a state machine are enabled by the same event occurrence, which transition is fired depends on the language variant (Harel original StateCharts, UML, Rhapsody, etc.) supported by the execution tool. Tools usually provide only one implementation of SVPs. It complicates communication both between tools and end-users, and hinders the co-existence of multiple variants. More generally, Language Workbenches dedicated to the specification and implementation of eXecutable Domain-Specific Modeling Languages (xDSMLs) often do not offer the tools and facilities to manage these SVPs, making it a time-consuming and troublesome activity. In this paper, we describe a modularized approach to the operational execution semantics of xDSMLs and show how it allows us to manage SVPs. We illustrate this proposal on StateCharts

Weaving Concurrency in eXecutable Domain-Specific Modeling Languages

International audienceThe emergence of modern concurrent systems (e.g., Cyber-Physical Systems or the Internet of Things) and highly-parallel platforms (e.g., many-core, GPGPU pipelines, and distributed platforms) calls for Domain-Specific Modeling Languages (DSMLs) where concurrency is of paramount importance. Such DSMLs are intended to propose constructs with rich concurrency semantics, which allow system designers to precisely define and analyze system behaviors. However , specifying and implementing the execution semantics of such DSMLs can be a difficult, costly and error-prone task. Most of the time the concurrency model remains implicit and ad-hoc, embedded in the underlying execution environment. The lack of an explicit concurrency model prevents: the precise definition, the variation and the complete understanding of the semantics of the DSML, the effective usage of concurrency-aware analysis techniques, and the exploitation of the concurrency model during the system refinement (e.g., during its allocation on a specific platform). In this paper, we introduce a concurrent executable metamodeling approach, which supports a modular definition of the execution semantics , including the concurrency model, the semantic rules, and a well-defined and expressive communication protocol between them. Our approach comes with a dedicated metalanguage to specify the communication protocol, and with an execution environment to simulate executable models. We illustrate and validate our approach with an implementation of fUML, and discuss the modularity and applicability of our approach