XML-based method and tool for handling variant requirements in domain models

Abstract

A domain model describes common and variant requirements for a system family. UML notations used in requirements analysis and software modeling can be extended with "variation points" to cater for variant requirements. However, UML models for a large single system are already complicated enough. With variants - UML domain models soon become too complicated to be useful. The main reasons are the explosion of possible variant combinations, complex dependencies among variants and inability to trace variants from a domain model down to the requirements for a specific system, member of a family. We believe that the above mentioned problems cannot be solved at the domain model description level alone. In the paper, we propose a novel solution based on a tool that interprets and manipulates domain models to provide analysts with customized, simple domain views. We describe a variant configuration language that allows us to instrument domain models with variation points and record variant dependencies. An interpreter of this language produces customized views of a domain model, helping analysts understand and reuse software models. We describe the concept of our approach and its simple implementation based on XML and XMI technologies.