. This paper presents a conceptual toolbox for software specification and design that contains techniques from structured and objectoriented specification and design methods. The toolbox is called TRADE (Toolkit for Requirements and Design Engineering). The TRADE tools are used in teaching informatics students structured and object-oriented specification and design techniques, but the toolkit may be of use to practicing software engineers as well. The conceptual framework of TRADE distinguishes external system interactions from internal components. External interactions in turns are divided into external functions, behavior and communication. The paper shows that structured and OO analysis offer a small number of specification techniques for these aspects, most of which can be combined in a coherent software design specification. It is also shown that the essential difference between structured and object-oriented software design approaches lies in the separation of data storage, data ...

This paper discusses the recent work of the authors in developing Integrated CASE (ICASE) tools which support multiple development notations. We use a four-step methodology to develop these integrated tools. The conceptual data models of different notations are first developed, and then merged into an integrated conceptual data model. Dynamic mappings between different notation components are used to describe how related notation components are kept consistent under change. The conceptual data models and mappings are used to implement individual CASE tools for each notation. Separate tools are then integrated by linking their repositories via a shared repository based on the integrated conceptual data model. We discuss extensions to this work which will provide MetaCASE facilities for environment generation and evolution

In this paper we develop a specification of requirements and conceptual design of a decision support system for the maintenance of the lamps in traffic regulation systems. Requirements and design are both specified using semiformal techniques in TRADE (Toolkit for Requirements and Design Engineering). The decision support system is non-trivial and provides an existing need in a company that works in the traffic system management area. The TRADE specification is based upon an existing algebraic specification in PSF (Process Specification Formalism). The rationale for doing this is that the PSF specification is very detailed and lacks a proper requirements specification. It turns out that TRADE, at least in this case, is much better suited as a means to specify abstract requirements. We discuss how algebraic specification could fit in a TRADE framework. 1 Introduction An important part of the maintenance of traffic light is lamp replacement. According to the Dutch firm Nederland Haarlem...

A new method for providing integrated support for multiple development notations (including analysis, design, and implementation) within Information Systems Engineering Environments (ISEEs) is described. Our method supports both static integration of multiple notations and the implementation of dynamic support for them within an integrated ISEE. First, conceptual data models of different analysis and design notations are identified and modelled, and then merged into an integrated conceptual data model. Second, mappings are derived from the integrated conceptual data model, which translates data changes in one notation to appropriate data changes in the other notations. Third, individual ISEEs for each notation are developed. Finally, the individual ISEEs are integrated via an integrated repository based on the integrated conceptual data model and mappings. An environment supporting integrated tools for Object-Oriented Analysis and Extended EntityRelationship diagrams is described, which has been built using this technique.

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