Structured Algebraic Nets with Object-Orientation

Abstract

The aim of this paper is to briefly introduce the Concurrent Object-Oriented Petri Net specification language CO-OPN/2 which has overcome some limitations of its object-based ancestor CO-OPN. Classes are described by means of algebraic nets in which places play the role of attributes, and methods function as external parameterized transitions. Inheritance and sub-typing are distinguished, with the former is considered as a mechanism for reuse while the later is viewed on a semantic level, based on the substitutability principle with respect to the behavior of the objects. As in the CO-OPN language, cooperation between the objects is achieved by means of synchronization expressions which allow the designer to select object interaction policies. 1 Introduction In recent years several formalisms based on P/Tnets with structuring capabilities have been developed, and many of these have adopted the objectorientation paradigm. Among these is included the CO-OPN (Concurrent Object-Oriented P...