Extending the UML Metamodel to Provide Support for Crosscutting Concerns

Aspect-orientation is a term used to describe approaches that explicitly capture, model and implement crosscutting concerns (or aspects). There is currently a number of new programming languages as well as extensions to current programming languages, the design dimensions of most of which have been influenced by the AspectJ language through three concepts and their respective constructs, namely join points, point cuts and advice which can support two principles recognized as being key concepts of aspect-oriented programming (AOP): quantification and obliviousness. At the modeling level, the reception of AOP has long been focused on the modeling of AspectJ programs, and there exists no model that is generic enough to capture non-AspectJ aspects either as a source language during forward engineering or as a target language during reverse engineering. In this paper, we present an extension to the UML metamodel to explicitly capture crosscutting concerns. The model is independent from any programming language and abstracted away from platform specific details. An instantiation of the newly created metamodel can be represented in standard XMI format, which enables current CASE tools to read and to visualize the instance models in UML. This language-independent aspectual description can support model transformations vital to software development and maintenance, such as forward engineering, reverse engineering, and reengineering.