An Evaluation of Maintainability of Aspect-Oriented Systems: a Practical Approach

Maintenance of software systems is becoming major concern for software developers and users. In software projects/products, where software changes/updates are frequently required to improve software quality, maintainability is an important characteristic of ISO 9126 quality standard to evaluate. Analyzability, changeability, stability, and testability are sub attributes/characteristics of maintainability in ISO 9126. In this paper, changeability is measured by making changes at code level of an AspectOriented (AO) system. The approach taken to evaluate the changeability of an AO system is to compute the impact of changes made to modules of the system. Some projects in aspect-oriented programming (AOP) language, AspectJ, have been taken for testing. The results suggest that the AO system can easily absorb changes and AO design metrics can be used as indicators of changeability as well as of maintainability. The results also suggest that a code level change in AO systems not always cause less change impact to other modules than a code level change in Object-Oriented (OO) systems.