Movie Database Case: An EMF-IncQuery Solution

Automated model transformations are frequently integrated to modeling environments, requiring both high performance and a concise programming interface to support software engineers. The objective of the EMF-INCQUERY [2] framework is to provide a declarative way to define queries over EMF models. EMF-INCQUERY extended the pattern language of VIATRA with new features (including transitive closure, role navigation, match count) and tailored it to EMF models [1]. EMF-INCQUERY is developed with a focus on incremental query evaluation. The latest developments extend this concept by providing a preliminary rule execution engine to perform transformations. As the engine is under heavy development, the design of a dedicated rule language (instead of using the API of the engine) is currently subject to future work. Conceptually, the environment relies on graph transformation (GT) rules: conditions are specified as EMF-INCQUERY patterns, while model manipulation and environment configuration is managed using the Xtend language [3]. One case study of the 2014 Transformation Tool Contest describes a movie database transformation [4]. The main characteristics of the transformation related to the application of EMF-INCQUERY are that i) it only adds new elements to the input model (i.e. couple and group are does not modify the input model), and ii) it is non-incremental (i.e. creating a new group will not affect rule applicability). The rest of the paper is structured as follows: Section 2 gives an overview of the implementation, Section 3 describes the solution including measurement results, and Section 4 concludes our paper.