Olivier Biberstein

Object-oriented nets with algebraic specifications: the CO-OPN/2 formalism

This paper presents and formally defines the CO-OPN/2 formalism (Concurrent Object-Oriented Petri Net) which is devised for the specification of large concurrent systems. We introduce the basic principles of the formalism, and describe how some aspects of objectorientation - such as the notions of class/object, object reference, inheritance and subtyping - are taken into account. In CO-OPN/2, classes (considered as templates) are described by means of algebraic nets in which places play the role of attributes, and methods are external parameterized transitions. A semantic extension for the management of the object references is defined. Inheritance and subtyping are clearly distinguished. Interaction between objects consists of synchronizations. Synchronization expressions are provided which allow the designer to select interaction policies between the partners. We also provide a step semantics which expresses the true concurrency of the object behaviors. Finally, in order to illustrate the modeling capabilities of our formalism, we adopted a case study on groupware or, more specifically, on a cooperative editor of hierarchical diagrams.

CO-OPN/2: a concurrent object-oriented formalism

In this article we present the concurrent object-oriented specification language CO-OPN/2 which extends the CO-OPN (Concurrent Object Oriented Petri Nets) formalism, destined to support the specification of large distributed systems. The CO-OPN/2 approach proposes a specification language, based on the object-oriented paradigm, which includes a fine description of true concurrent behavior.