Realizing changes by aspects at the design level

The cost of a change is high, but changes are an inevitable part of software development lifecycle, which comes to be recognized under a more general term: software evolution. To mitigate this problem, an approach to aspect-oriented change realization has been proposed earlier based on the idea of representing change by aspect. In many cases, software development relies on graphical modeling, mainly UML, and thus a legitimate question is how aspect-oriented change realization could be supported at the modeling level. This paper proposes an approach to achieve this based on Theme, a comprehensive approach to aspect-oriented analysis and design. One of the results of the work reported here is a catalog of change type models for the domain of web applications comprising the models of eleven specification change types and seven implementation change types. Apart from the examples presented in the paper, the approach was successfully applied to a real web mail system. As no dedicated Theme modeling tool is available, a UML profile for both analytical (Theme/Doc) and design part (Theme/UML) of the Theme approach has been designed and implemented in IBM Rational Software Architect.