Requirements analysis and UML - interaction diagrams and state transition diagrams

Abstract

UML provides a powerful framework and notation for modelling business processes and objects. In part 1 of this article four arguments for conceptual modelling were advanced: to clarify our thinking about an area of concern; as an illustration of a concept; as an aid to defining structure and logic; and, as a prerequisite to design. The unified modelling language (UML) is a widely accepted object-oriented notation for modelling and specifying system requirements. In part 1, the UML use case diagram and class diagram were introduced and applied to the fictional Barchester Playhouse, an organisation investigating the implementation of an Internet theatre ticket booking system. Use cases represent the system from a functional, user-centred perspective, while the class diagram exposes the structure of the system. In this article, the behavioural and dynamic aspects are explored using interaction diagrams and state transition diagrams.