Flexible Interconnection of Graph Transformation Modules

Modularization is a well-known concept to structure software systems as well as their specifications. Modules are equipped with export and import interfaces and thus can be connected with other modules requesting or providing certain features. In this paper, we study modules the interfaces of which consist of behavioral specifications given by typed graph transformation systems. We introduce a framework for classifying and systematically defining relations between typed graph transformation systems. The framework comprises a number of standard ingredients, like homomorphisms between type graphs and mappings between sets of graph transformation rules. The framework is applied to develop a novel concept of substitution morphism by separating preconditions and effects in the specification of rules. This substitution morphism is suited to define the semantic relation between export and import interfaces of requesting and providing modules.