High-Level Petri Nets with Object-Orientation - A High-Level Petri Net Model Allowing Multiple Inheritance and Multiple Polymorphism

This paper presents a high-level Petri net model called High-Level Petri Nets with Object-Orientation (HLPNOO), a new approach for introducing object-oriented concepts into the framework of Petri nets. An important feature of the HLPNOO formalism is the fact that it allows distinct hierarchies for subtyping and sub-classing. We use order-sorted algebras in order to specify the notion of subtyping for object type hierarchies. Moreover we use the notions from category theory and institutions in order to allow composable Petri nets and multiple inheritance. We use encapsulated multi-methods and a multi-dispatching mechanism for messages in order to safety integrate the concepts of covariant and contravariant specialization of inherited methods and to allow the multiple polymorphism.