Extension to UML-B Notation and Toolset

The UML-B notation has been created as an attempt to combine the success and ease of use of UML, with the verification and rigorous development capabilities of formal methods. However, the notation currently only supports a basic diagram set. To address this we have, in this project, designed and implemented a set of extensions to the UML-B notation that provide a much fuller software engineering experience, critically making UML-B more appealing to industry partners. These extensions comprise five new diagram types, which are aimed at supplying a broader range of design capabilities, such as conceptual Use-Case design and future integration with the ProB animator tool

A Model Driven Approach to the Analysis of Timeliness Properties

Abstract. The need for a design language that is rigorous but accessible and intuitive is often at odds with the formal and mathematical nature of languages used for analysis. UML and Petri Nets are a good example of this dichotomy. UML is a widely accepted modelling language capable of modelling the structural and behavioural aspects of a system. However UML lacks the mathematical foundation that is required for rigorous analysis. Petri Nets on the other hand have a strong mathematical base that is well suited for analysis of a system but lacks the appeal and ease-of-use of UML. Design in UML languages such as Sequence Diagrams and analysis in Petri Nets require on one hand some expertise in potentially two incompatible systems and their tools, and on the other a seamless transition from one system to the other. One way of addressing this impediment is to focus the software development mainly on the design language system and to facilitate the transition to the formal analysis by means of a combination of automation and tool support. The aim of this paper is to present a transformation system, which takes UML Sequence Diagrams augmented with time constraints and generates semantically equivalent Petri Nets that preserve the timing requirements. A case study on a small network is used in order to illustrate the proposed approach and in particular the design, the transformation and the analysis processes.

Using formal metamodels to check consistency of functional views in information systems specification

UML notations require adaptation for applications such as Information Systems (IS). Thus we have defined IS-UML. The purpose of this article is twofold. First, we propose an extension to this language to deal with functional aspects of IS. We use two views to specify IS transactions: the first one is defined as a combination of behavioural UML diagrams (collaboration and state diagrams), and the second one is based on the definition of specific classes of an extended class diagram. The final objective of the article is to consider consistency issues between the various diagrams of an IS-UML specification. In common with other UML languages, we use a metamodel to define IS-UML. We use class diagrams to summarize the metamodel structure and a formal language, B, for the full metamodel. This allows us to formally express consistency checks and mapping rules between specific metamodel concepts. (C) 2007 Elsevier B.V. All rights reserved

Towards a method for rigorous development of generic requirements patterns

We present work in progress on a method for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. Our chosen application domain is the failure detection and management function for engine control systems: here generic requirements drive a software product line of target systems. A pilot formal specification and design exercise is undertaken on a small (twosensor) system element. This exercise has a number of aims: to support the domain analysis, to gain a view of appropriate design abstractions, for a B novice to gain experience in the B method and tools, and to evaluate the usability and utility of that method.We also present a prototype method for the production and verification of a generic requirement set in our UML-based formal notation, UML-B, and tooling developed in support. The formal verification both of the structural generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

Towards a methodology for rigorous development of generic requirements patterns

We present work in progress on a methodology for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. We consider the failure detection and management function for engine control systems as an application domain where product line engineering is useful. The methodology produces a generic requirement set in our, UML based, formal notation, UML-B. The formal verification both of the generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

An open extensible tool environment for Event-B

Abstract. We consider modelling indispensable for the development of complex systems. Modelling must be carried out in a formal notation to reason and make meaningful conjectures about a model. But formal modelling of complex systems is a difficult task. Even when theorem provers improve further and get more powerful, modelling will remain difficult. The reason for this that modelling is an exploratory activity that requires ingenuity in order to arrive at a meaningful model. We are aware that automated theorem provers can discharge most of the onerous trivial proof obligations that appear when modelling systems. In this article we present a modelling tool that seamlessly integrates modelling and proving similar to what is offered today in modern integrated development environments for programming. The tool is extensible and configurable so that it can be adapted more easily to different application domains and development methods.

UML-B and Event-B: an integration of languages and tools

UML-B is a graphical front end for Event-B. It adds support for class-oriented modelling but retains the Event-B concept of a closed system characterized by families of spontaneous events. UML-B is similar to UML but is essentially a new notation based on a separate meta-model. We provide tool support for UML-B, including drawing tools and a translator to generate Event-B models. The tools are closely integrated with the Event-B verification tools so that when a drawing is saved the translator automatically generates the corresponding Event-B model. The Event-B verification tools (syntax checker and prover) then run automatically providing an immediate display of problems. We introduce the UML-B notation its tool support and its integration with Event-B