Empowering UML application design with task models

Abstract

This paper describes a practical method to include task modelling into Unified Modeling Language-based (UML-based) software engineering. The reason for this undertaking is increasing awareness of the capability and handiness of task models to picture the functionalities of a system (as awaited by customers), but also the lack of expressive power of UML use case diagrams, when underspecified, to make the functionalities of a system fully understandable to software developers. The described method builds on a task modelling software, a plugin transforming task models into use case diagrams and use case descriptions, and a UML software enabling to display use case diagrams. The plugin puts a set of rules interpreting the content of task models at work, in order to generate an XML file readable by the UML software, and a ready-to-use PDF output containing the use case descriptions. The advantages of this workflow are to enforce the link between the different project stakeholders (customer, architect, developers), to allow for cost-free iterations affecting the requirement scheme, to enable usable incremental modelling and to introduce interface design into the first step of the design process.