Domain-specific model verification with QVT

Model verification is the process of checking models for known problems (or anti-patterns). We propose a new approach to declaratively specify and automatically detect problems in domain-specific models using QVT (Query/View/Transformation). Problems are specified with QVT-Relations transformations from models where elements involved in problems are identified, to result models where problem occurrences are reported in a structured and concise manner. The approach uses a standard formalism, applies generically to any MOF-based modeling language and has well-defined detection semantics. We apply the approach by defining a catalog of problems for a particular but important kind of models, namely metamodels. We report on a case study where we used the catalog to verify recent revisions of the UML metamodel. We detected many problem occurrences that we analyzed and helped resolve in the (latest) UML 2.4 revision. As a result, the metamodel was found to have improved dramatically by the experts defining it.