Iain Sommerville

Viewpoints: principles, problems and a practical approach to requirements engineering

The paper includes a survey and discussion of viewpoint‐oriented approaches to requirements engineering and a presentation of new work in this area which has been designed with practical application in mind. We describe the benefits of viewpoint‐oriented requirements engineering and describe the strengths and weaknesses of a number of viewpoint‐oriented methods. We discuss the practical problems of introducing viewpoint‐oriented requirements engineering into industrial software engineering practice and why these have prevented the widespread use of existing approaches.We then introduce a new model of viewpoints called Preview. Preview viewpoints are flexible, generic entities which can be used in different ways and in different application domains. We describe the novel characteristics of the Preview viewpoints model and the associated processes of requirements discovery, analysis and negotiation. Finally, we discuss how well this approach addresses some outstanding problems in requirements engineering (RE) and the practical industrial problems of introducing new requirements engineering methods.

Viewpoints for requirements definition

This paper is a survey of the current viewpoint-oriented requirements approaches and a description of an alternative object-oriented viewpoint-based approach. The paper sets out a case for a multiple viewpoint-oriented approach in requirements definition and, using a simple case study, examines the viewpoint approach adopted by three requirements methodologies. The paper concludes by proposing an alternative object-oriented viewpoint-based approach.

Architectural support for cooperative multiuser interfaces

Computer support for cooperative work requires the construction of applications that support interaction by multiple users. The highly dynamic and flexible nature of cooperative work makes the need for rapid user-interface prototyping a central concern. We have designed and developed a software architecture that provides mechanisms to support rapid multiuser-interface construction and distributed user-interface management. Rapid prototyping requires mechanisms that make the information determining interface configuration visible, accessible, and tailorable. We developed the architecture as part of a project investigating support for the cooperative work of air traffic controllers. Extensive use of prolonged ethnographic investigation helped to uncover the nature of cooperation in air traffic control. The aim of the architecture is to support an environment in which a multidisciplinary team can experiment with a wide range of alternate user-interface designs for air traffic controllers. Thus, we use examples from this domain to illustrate the architecture.<<ETX>>

Interacting with an active, integrated environment

Software engineering environments are intended to provide a cohesive and integrated set of tools to support the process of software engineering with much current research into environment design focussed on maximising the degree to which these tools can be integrated. This paper describes the architecture of a prototype environment which attempts to achieve a high degree of integration using techniques drawn from artificial intelligence, office automation and object-oriented programming. This environment is implemented as a federation of intelligent, co-operating agents which communicate, with each other and with users, by message passing. This paper is particularly concerned with user interface integration including the mechanisms employed to permit inter-agent and agent-user communications.

Direct manipulation of an object store

Integrated project support environments (IPSEs) are intended to provide a cohesive and integrated set of tools to support the process of design and development in software engineering projects. Much current research is concentrated on maximising the degree to which these tools can be integrated. This paper briefly describes the architecture of a prototype IPSE which attempts to achieve a high degree of integration using techniques drawn from the disciplines of intelligent knowledge-based systems, office automation and object-oriented programming. The remainder of the paper deals with the design of a user interface to the IPSE based on direct manipulation. It argues that this provides a consistent and integrated method with which users can interact with the objects in the IPSEs object store.

Database object display definition and management with Moggetto

This paper describes a user interface framework called Moggetto for an object-oriented database system (OODB). Moggetto is proposed as an approach to the definition and management of tailorable object displays. The novelty of the approach lies in the use of embedded, inherently reconfigurable user interface components to realise object user interfaces which are modelled in the database. This obviates the need for close coupling between the OODB and the host windowing system through, for example, common language bindings and code libraries.

Distributed systems management as a group activity

It is important to consider systems management as part of a whole organizational management strategy, and, as such, to be aware of the impact of people on management. Within a flexible management framework we bring people within the terms of reference associated with systems management.<<ETX>>