Uniform Genericity for Aspect Languages

Aspect-oriented programming languages promise to provide better modularity than pure object-oriented decomposition. A typical benefit of increased modularity is ease of maintenance, evolution and reuse. However, it has been noted by various researchers that many of the first generation aspect languages do not provide the degree of reusability initially hoped for. In this paper, we argue that the problem is due to a lack of support for aspect genericity, respectively to a lack of support for a sufficiently powerful kind of genericity. We introduce the concept of uniform genericity for aspect languages and discuss in which ways it goes beyond previous approaches to generic aspects. Then we present LogicAJ, a uniformly generic aspect language. Using LogicAJ as an example, we show how uniform aspect genericity recommends itself for implementing reusable solutions of various problems discussed in literature, ranging from the generic replacement of object instantiation, over verification of constraints and conventions, to the generic implementation of design pattern variants. We believe uniform genericity to be an important ingredient for second generation aspect languages whose aspects are only loosely coupled to base programs, thus easing aspect reuse and independent evolution of aspects and base programs.