Defining Operational Behavior of Object Specifications by Attributed Graph Transformations

. A single pushout approach to the transformation of attributed partial graphs based on categories of partial algebras and partial morphisms is introduced. A sufficient condition for pushouts in these categories is presented. As the synchronization mechanism we use amalgamation of rules and show how synchronization can be minimized. We point out how the results obtained can be employed in order to define an operational semantics for object specification languages. 1 Introduction Graphs and graph grammars usually yield intuitive descriptions of complex phenomena in computer science. Therefore, numerous approaches to graph grammars have been put forward, among them the logical approach [6], the set theoretic approach [29], and the algebraic approach [9]. Graph-based techniques have for instance been successfully applied in the realm of software engineering development environments [13, 14], for object-oriented languages based on asynchronous communication [22, 24, 20, 21] and in logic p..