Extending high-level Petri nets for object-oriented design

An integrated model for the high level representation of both the structural and the functional properties of complex concurrent real-time systems is presented. The model, called τ-nets, based on an extension to high-level Petri nets, is hierarchical, includes a type-checking mechanism, and supports the definition of taxonomic hierarchies of token, node and arc types. The proposed extensions of high-level Petri nets are thus embedded in an object-oriented development framework. τ-nets allow a type safe utilization of Petri nets in a multiparadigm programming environment. Petri nets are used to describe the dynamic relationships among different communicating processes while a functional language is used to specify the code tied with the firing of each transition. Every part of the system is strongly object-oriented. Nets, nodes, arcs and tokens belong to disjoint hierarchies of types supporting a single inheritance mechanism