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

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. 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.