Aspects and Annotations for Controlling the Roles Application Classes Play for Design Patterns

Design patterns are an invaluable resource for developers. Yet, for some of them the implementation of an application concern and the code needed to enforce the design pattern solution can be tangled within the same class. This potent ially makes classes more complex, more prone to changes and less reusable. In order to keep the complexity of classes under manageable levels, this paper proposes a solution based on aspect-orientation. Our solution makes aspects and application classes independent of each other, while connecting code is used to concisely express the role played by classes within design patterns. Developers needing to modify the role of an application class should only update such connecting code, thus keeping changes to application code to a minimum. The performance overhead of such an approach is evaluated and compared with the standard implementation.