Behavior-consistent specialization of object life cycles

Abstract

Object-oriented design methodologies represent the behavior of instances of an object type not merely by a set of operations, but also by providing an overall description on how instances evolve over time. Such a description is often referred to as "object life cycle."Object-oriented systems organize object types in hierarchies in which subtypes inherit and specialize the structure and behavior of their supertypes. Past experience has shown that unrestricted use of inheritance mechanisms leads to system architectures that are hard to understand and to maintain, since arbitrary differences between supertype and subtype are possible. Evidently, this is not a desirable state of affairs and the behavior of a subtype should specialize the behavior of its supertype according to some clearly defined consistency criteria. Such criteria have been formulated in terms of type systems for semantic data models and object-oriented programming languages. But corresponding criteria for the specialization of object life cycles have so far not been thoroughly investigated.This paper defines such criteria in the realm of Object Behavior Diagrams, which have been originally developed for the design of object-oriented databases. Its main contributions are necessary and sufficient rules for checking behavior consistency between object life cycles of object types in specialization hierarchies with multiple inheritance.

Process Compliance Measurement Based on Behavioural Profiles

“…A model inherits the behaviour of a parent model, if it shows the same external behaviour when all actions that are not part of the parent model are either blocked (protocol inheritance) or hidden (projection inheritance). Similar ideas have been presented in [14,15]. The boolean characteristics of these notions have been criticized as inadequate for many process measurement scenarios [2].…”

A Foundational Approach for Managing Process Variability

“…Behavioural profiles provide an abstraction which approximates trace equivalence at the weaker end of this spectrum. Notions of inclusion are discussed in work on behavioural equivalence [7,8,9]. Recent works calculate a degree of behavioural similarity between process models based on linguistic, graphmatching, and state-based concepts, see [31] for an overview.…”

“…Throughout this paper, we will demonstrate that the essential variant management questions can be answered based on set algebraic operations of complementation, intersection, and union, and the relations of set equivalence and inclusion. Although there are several works on particular subsets of these aspects such as inclusion (or behaviour inheritance) [7,8,9] and union (or merging behaviour) [10,11,12,13], we currently miss an overarching set algebra which provides the means to efficiently calculate with behaviour.…”

“…Existing work on behaviour inheritance [8,9,14] builds on an adapted notion of branching bisimilarity. That is, activities that are without counterpart can either be blocked or hidden when assessing behavioural equivalence.…”

Efficient Computation of Causal Behavioural Profiles Using Structural Decomposition

“…Moreover, work on equivalence-preserving refinements for Petri nets, refer to [38] for a thorough survey, illustrates that common notions of equivalence are preserved solely under certain refinement operators. Similarly, work on net morphisms [39] and behaviour inheritance [40,41] shows that any extension of a net has to be done in a structured manner in order to preserve common equivalences. Third, notions of behavioural equivalence are computationally hard, which precludes an application for large scale industrial process models.…”