A Formally Grounded Software Specification Method

One of the goals of software engineering is to provide what is necessary to write relevant, legible, useful descriptions of the systems to be developed, which will be the basis of successful developments. This goal was addressed both from informal approaches (providing in particular visual notations) and formal ones (providing a formal sound semantic basis). Informal approaches are often driven by a software development method, and, while formal approaches sometimes provide a user method, it is usually aimed at helping to use the proposed formalism when writing a speci\ufb01cation. Our goal here is to provide a companion method that helps the user to understand the system to be developed, and to write the corresponding formal speci\ufb01cations. We also aim at supporting visual presentations of formal speci\ufb01cations, so as to \u201cmake the best of both formal and informal worlds\u201d. We developed this method for the (logical-algebraic) speci\ufb01cation languages Casl (Common Algebraic Speci\ufb01cation Language, developed within the joint initiative CoFI) and for an extension for dynamic systems Casl-Ltl, and we believe it is general enough to be adapted to other paradigms. Another challenge is that a method that is too general does not encompass the different kinds of systems to be studied, while too many different specialized methods result in partial views that may be difficult to integrate in a single global one. We deal with this issue by providing a limited number of instances of our method, \ufb01tted for three different kinds of software items, while keeping a common \u201cmeta\u201d- structure and way of thinking. More precisely, we consider here that a software item may be a simple dynamic system, a structured dynamic system, or a data structure, and we show here how to support property-oriented (axiomatic) speci\ufb01cations. We are thus providing support for the \u201cbuilding-bricks\u201d tasks of specifying software artifacts that in our experience are needed for the development process. Our approach is illustrated with a lift case study

CASL-MDL, modelling dynamic systems with a formal foundation and a UML-like notation

In this paper we present a part of Casl-Mdl, a visual modelling notation based on Casl-Ltl (an extension for dynamic system of the algebraic specification language Casl). The visual constructs of Casl-Mdl have been borrowed from the UML, thus existing editors may be used. A Casl-Mdl model is a set of diagrams but it corresponds to a Casl-Ltl specification, thus Casl-Mdl is a suitable means to easily read and write large and complex Casl-Ltl specifications. We use as a running example a case study that describes the functioning of a consortium of associations

Using UML for Problem Frame Oriented Software Development

We propose a software development approach that combines the use of the UML notation, the use of the structuring concepts provided by the problem frames, together with our methodological approach for wellfounded methods. The problem frames are used to provide a rst idea of the main elements of the problem under study. Then we provide ad hoc UML based development methods for some of the most relevant problem frames together with precise guidelines for the users. The general idea of our method is that, for each frame, several artifacts have to be produced, each one corresponding to a part of the frame. The description level may range from informal and sketchy, to formal and precise, while this approach is drawn from experience in formal speci cations

Activity Diagrams Patterns for Modeling Business Processes

Designing and analyzing business processes is the starting point of the development of enterprise applications, especially when following the SOA (Service Oriented Architecture) paradigm. UML activity diagrams are often used to model business processes. Unfortunately, their rich syntax favors mistakes by designers; furthermore, their informal semantics prevents the use of automated verification techniques. In this paper, (i) we propose activity diagram patterns for modeling business processes, (ii) we devise a modular mechanism to compose diagram fragments into a UML activity diagram, and (iii) we propose a semantics for the produced activity diagrams, formalized by colored Petri nets. Our approach guides the modeler task (helping to avoid common mistakes), and allows for automated verification

Formal or not, but Precise Modelling of Services with CASL4SOA and SoaML

The emergence of service-oriented architecture (SOA) enables business functionalities to be invoked over a remote network, and thus requires speci\ufb01c modelling methods to develop service-oriented solutions. In this paper, we focus on precise service modelling and provide two approaches, one based on a standard widespread not formal notation (SoaML), and the other based on a formal notation (CAS L 4 SOA). We chose SoaML introduced by OMG as a standard UML pro\ufb01le for modelling services, and CAS L 4 SOA, a formal visual notation for service oriented systems based on CAS L that resulted from a uni\ufb01cation effort of the algebraic speci\ufb01cation approaches using a case study