On Leveraging UML/OCL for Model Synchronization

Modelling complex system often results in different but overlapping modelling artifacts which evolve independently. Thus, inconsistencies may arise which lead to unintended effects on the modelled system. To mitigate this situation, model synchronization is seen as a recurring and crucial maintenance task which requires to restore consistency between multiple models using the most suitable changes. Currently, different languages and tools are used for inter-model consistency management than for intra-model consistency where UML/OCL is an accepted solution. Consequently, the result of synchronizing models solely based on inter-model constraints might result into inappropriately evolved models w.r.t. intra-model constraints. In this paper, we present a synchronization model formalized in UML/OCL which covers explicit consistency and change models including costs and which considers both, inter-model and intra-model constraints at the same time. Instances of this synchronization model represent successful synchronization scenarios. In particular, models can be synchronized, also taking into account their predecessor versions, by finding a constraint violation-free extension of a partial model including those instances which may be optimized for minimal cost. We prototypically implemented this approach using a model finder to automatically retrieve synchronized models and the change operations to compute them by completing the partial model.