This paper presents a methodology for agent-oriented analysis and design. The methodology is general, in that it is applicable to a wide range of multi-agent systems, and comprehensive, in that it deals with both the macro-level (societal) and the micro-level (agent) aspects of systems. The methodology is founded on the view of a system as a computational organisation consisting of various interacting roles. We illustrate the methodology through a case study (an agent-based business process management system).

Is there such a thing anymore as a software system that doesn't need to be secure? Almost every softwarecontrolled system faces threats from potential adversaries, from Internet-aware client applications running on PCs, to complex telecommunications and power systems accessible over the Internet, to commodity software with copy protection mechanisms. Software engineers must be cognizant of these threats and engineer systems with credible defenses, while still delivering value to customers. In this paper, we present our perspectives on the research issues that arise in the interactions between software engineering and security.

Goals are a logical mechanism for identifying, organizing and justifying software requirements. Strategies are needed for the initial identification and construction of goals. In this paper we discuss goals from the perspective of two themes: goal analysis and goal evolution. We begin with an overview of the goal-based method we have developed and summarize our experiences in applying our method to a relatively large example. We illustrate some of the issues that practitioners face when using a goal-based approach to specify the requirements for a system and close the paper with a discussion of needed future research on goalbased requirements analysis and evolution. 1 Introduction Goal-based methods stress the need to characterize, categorize, decompose and structure goals as requirements, but usually fail to offer strategies to identify goals, taking it for granted that the goals have already been documented [1] [4] [12]. If goals have not been previously documented, how do we first...

System testing is concerned with testing an entire system based on its specifications. In the context of object-oriented, UML development, this means that system test requirements are derived from UML analysis artifacts such as use cases, their corresponding sequence and collaboration diagrams, class diagrams, and possibly Object Constraint Language (OCL) expressions across all these artifacts. Our goal here is to support the derivation of functional system test requirements, which will be transformed into test cases, test oracles, and test drivers once we have detailed design information. In this paper, we describe a methodology in a practical way and illustrate it with an example. In this context, we address testability and automation issues, as the ultimate goal is to fully support system testing activities with high-capability tools.

A program's object model captures the essence of its design. For some programs, no object model was developed during design; for others, an object model exists but may be out-of-sync with the code. This paper describes a tool that automatically extracts an object model from the classfiles of a Java program. Unlike existing tools, it handles container classes, by inferring the types of elements stored in a container, and eliding the container itself. This feature is crucial for obtaining models that show the structure of the abstract state, and bear some relation to conceptual models. Although the tool performs only a simple, heuristic analysis that is almost entirely local, the resulting object model is surprisingly accurate. The paper explains what object models are and why they are useful; describes the analysis, its assumptions and limitations; evaluates the tool for accuracy, and illustrates its use, on a suite of sample programs. 1 Introduction Womble is a tool that extracts obj...

An approach for guiding the construction of use case specifications is presented. A use case specification comprises contextual information of the use case, its change history, the complete graph of possible pathways, attached requirements and open issues. The proposed approach delivers a use case specification as an unambiguous natural language text. This is done by a stepwise and guided process which progressively transforms initial and partial natural language descriptions of scenarios into well structured, integrated use case specifications. The basis of the approach is a set of linguistic patterns and linguistic structures. The former constitutes the deep structure of the use case specification whereas the latter corresponds to the surface structures. The paper presents the use case model, the linguistic basis and the guided process along with the associated guidelines and support rules. The process is illustrated with the automated teller machine (ATM) case study.

The Unified Modeling Language (UML) is rapidly emerging as a de-facto standard for modelling OO systems. Given this role, it is imperative that the UML have a welldefined, fully explored semantics. Such semantics is required in order to ensure that UML concepts are precisely stated and defined. In this paper we describe and motivate an approach to formalizing UML in which formal specification techniques are used to gain insight into the semantics of UML notations and diagrams. We present work carried out by the Precise UML (PUML) group on the development of a precise semantic model for UML class diagrams. The semantic model is used as the basis for a set of diagrammatical transformation rules, which enable formal deductions to be made about UML class diagrams. It is also shown how these rules can be used to verify whether one class diagram is a valid refinement (design) of another. Because these rules are presented at the diagrammatical level, it will be argued that UML can be successfully used as a formal modelling tool without the notational complexities that are commonly found in formal specification techniques.

The Unified Modeling Language (UML) is likely to become an important industry standard language for modelling object-oriented systems. However, its use as a precise analysis tool is limited due to a lack of precise semantics and practical analysis techniques. This paper proposes a rigorous analysis technique for UML based on the use of diagrammatical transformations. A precise description of a subset of UML class diagrams is presented. This is then used to identify a number of deductive transformations on class diagrams. Conditions for checking the soundness of the rules are also given. Because the reasoning system is based on the manipulation of diagrams, it is proposed that they can be successfully used by practitioners without recourse to complex linguistic proof techniques. 1

Abstract. The use of scenarios has become a popular technique for requirements elicitation and specification building. Since scenarios capture only partial descriptions of system behavior, an approach for scenario composition and integration is needed to produce more complete specifications. The Unified Modeling Language (UML), which is emerging as a unified notation for objectoriented modeling, provides a suitable framework for scenario acquisition using Use Case diagrams and Collaboration diagrams and for behavioral specification using StateChart diagrams; yet it does not propose any specific modeling process, let alone a process for transforming scenarios into behavioral specifications. In this paper, we suggest a four-step process for synthesizing behavioral specifications from scenarios. It generates from a given set of Collaboration diagrams the StateChart diagrams of all the objects involved. Our approach is incremental and is fully compliant with the UML. Furthermore, it provides an elegant solution to the problem of scenario interleaving. The underlying algorithm has been implemented and validated with several examples, and is fit for integration into CASE tools supporting the UML. 1

There is much interest in developing a firm semantic basis for object-oriented modeling concepts. By providing precise characterizations of object-oriented (OO) modeling concepts one gains the ability to build precise OO models of behavior and structure that can be rigorously analyzed. In this paper we present the current results of our ongoing formalization of the Unified Modeling Language (UML). UML is a proposed common OO modeling language, thus it is important that it have a formally defined semantic base. The focus of this paper is the formalization of the primary UML constructs used to build class structures. We use the Z notation to precisely express the meaning of UML class structures. Keywords: Formal Specification Techniques, Integrated Methods, Object-Oriented Analysis and Modeling, Unified Modeling Language, Z. 1 Introduction Most popular graphical object-oriented (OO) modeling techniques provide mechanisms that allow one to: ffl abstract over details best left to later st...