Patterns for Refinement Automation

Abstract

Formal modelling is indispensable for engineering highly dependable systems. However, a wider acceptance of formal methods is hindered by their in-sufficient usability and scalability. In this paper, we aim at assisting developers in rigorous modelling and design by increasing automation of development steps. We introduce a notion of refinement patterns -generic representations of typical correctnesspreserving model transformations. Our definition of a refinement pattern contains a description of syntactic model transformations, as well as the pattern applicability conditions and proof obligations for verification of correctness preservation. This establishes a basis for building a tool supporting formal system development via pattern reuse and instantiation. We present a prototype of such a tool and some examples of refinement patterns for automated development in the Event B formalism. AbstractFormal modelling is indispensable for engineering highly dependable systems. However, a wider acceptance of formal methods is hindered by their in-sufficient usability and scalability. In this paper, we aim at assisting developers in rigorous modelling and design by increasing automation of development steps. We introduce a notion of refinement patterns -generic representations of typical correctness-preserving model transformations. Our definition of a refinement pattern contains a description of syntactic model transformations, as well as the pattern applicability conditions and proof obligations for verification of correctness preservation. This establishes a basis for building a tool supporting formal system development via pattern reuse and instantiation. We present a prototype of such a tool and some examples of refinement patterns for automated development in the Event B formalism. About the authorAlexei Ilasov is a Research Associate within the School of Computing Science, Newcastle University.Alexander Romanovsky is a Research Professor. He has been involved in a number of ESPRIT, FP and EPSRC/UK projects on system dependability within which a wide range of general fault tolerance mechanisms and architectures have been developed (DSoS, PDCS, DeVa, CaberNet, MAFTIA, ReSIST, DISCS, RODIN). He has been a co-investigator of two EPSRC/UK projects (DOTS and TrAmS). Now he is coordinating a major FP7 Integrated Project DEPLOY aiming to make major advances in engineering methods for dependable systems through the deployment of formal engineering methods in 5 sectors of European industry. His main interests are in fault tolerance, rigorous design of resilient systems, software architectures, exception handing, mobile agents and service oriented architectures. Abstract. Formal modelling is indispensable for engineering highly dependable systems. However, a wider acceptance of formal methods is hindered by their insufficient usability and scalability. In this paper, we aim at assisting developers in rigorous modelling and design by increasing automation of development steps. Suggested keywordsWe introduce a notion...

Event-B formalization of a variability-aware component model patterns framework

“…The generation of correct-by-construction B/Event-B refinements has already been studied. They either propose a dedicated language for the expression of patterns ( [24] for B, [17] for Event-B), or a pattern is seen as a usual Event-B machine that is mapped on the Event-B machine to be refined [15]. However, rather than focusing on patterns applied on Event-B models, our objective is the formalization using Event-B of the instantiation and the application of patterns for system architectures expressed using component models.…”

Use of Tabular Expressions for Refinement Automation

“…The refinement calculus provides a formal stepwise approach for constructing a program from an abstract program to a concrete program by preserving essential properties. There are a few papers published on automating the refinement pattern [4] and principles for refinement [5]. In [4], the authors propose refinement patterns using syntactic model transformation, pattern applicability conditions and proof obligations for verifying correctness preservation.…”

“…There are a few papers published on automating the refinement pattern [4] and principles for refinement [5]. In [4], the authors propose refinement patterns using syntactic model transformation, pattern applicability conditions and proof obligations for verifying correctness preservation. To handle the design complexity of applying Event-B refinement and consistency rules, one paper [5], presents refinement planning from an informal/semi-formal specification.…”

“…Practicalities of performing automatic refinements are largely an open problem. It is, clearly, unrealistic to carry out such refinements entirely by hand, which is well illustrated by the complexity of the examples in [4,5]. Some refinement steps are, however, inherently difficult to automate.…”

Component Based Software Architecture Refinement and Refactoring Method into Extreme Programming

“…Re-finement allows us to ensure that a refined, i.e., more elaborated, model retains all the essential properties of its abstract counterpart. Since refinement is transitive, the model-driven refinementbased development process enables development of systems correct-by construction [8].…”