Aspectual Mixin Layers

Feature-Oriented Programming (FOP) is an appropriate programming paradigm to implement program families and incremental designs. Beside numerous strengths in doing that FOP yields several drawbacks, especially regarding the ability to localize and modularize crosscutting concerns. This is exactly the strength of another prominent programming paradigm, Aspect-Oriented Programming (AOP). In this article we contribute a set of evaluation criteria as well as a detailed evaluation and comparison of AOP and FOP. The evaluation criteria are tailored especially for incremental software development. The evaluation reveals that aspects and features are not concurrent concepts. In fact AOP has several strengths to improve FOP in order to implement crosscutting features. Based on these results we introduce the novel notion of aspectual mixin layers (AMLs) that integrate AOP concepts into FOP. Our evaluation of AMLs reveals that they improve the crosscutting modularity of features. In a subsequent case study we clarify and discuss the benefits and limitations of AMLs. Finally, we suggest two potential derivates of AMLs that yield different promising properties.