An Aspect-Oriented Design Framework for Concurrent Systems

The goal of AOP is to achieve an improved separation of concerns in both design, and implementation. Our work concentrates on the aspectual decomposition of concurrent object-oriented systems. Following a component hierarchy within the object-oriented programming paradigm we categorized aspects as intra-method, intra-object and intra-package according to their hierarchical level of cross-cutting. We achieve composition of concerns, through the use of an object we call the moderator that coordinates the interaction of components and aspects while preserving the semantics of the overall system. As aspects can cut across components at every level, we view the moderator is a recurring pattern from intra-method to intra-package. Our design framework provides an adaptable model and a component hierarchy using a design pattern as well as it allows for an open language where new aspects (specifications) can be added and their semantics can be delivered to the compiler through the moderator. In essence the moderator is a program that extends the language itself. Our goal is to achieve separation of concerns and retain this separation without having to produce an intermingled source code.