xMOF: Executable DSMLs Based on fUML

The basic ingredients of a domain-specific modeling language (DSML) are its syntax and semantics. For defining the abstract syntax in terms of metamodels, MOF constitutes a standardized language. For specifying the behavioral semantics, however, no standardized language exists, which hampers the emergence of model execution facilities, such as debugging and simulation support. The contribution of this paper is an integrated approach for specifying the abstract syntax and behavioral semantics of DSMLs based exclusively on standardized modeling languages. In particular, we integrate fUML, a standardized executable subset of UML, with MOF leading to a new metamodeling language xMOF. Moreover, we propose a methodology for developing executable DSMLs fostering the separation of abstract syntax and behavioral semantics. To evaluate our approach, we provide an EMF-based implementation and report on lessons learned from performing three case studies in which we implemented executable DSMLs using xMOF.