Formal Models for Architecture Aspects and Their Weaving

Aspect-oriented concepts are currently introduced in early stages of software development to achieve better separation of concerns. However, at the architecture level, there exists no strict model for aspects and their weaving, which makes it difficult for analyzing and reasoning about the semantic problems introduced in the composition of the aspects and the base system. We present a formal model to specify architecture aspects. Its underlying formalism is Process Algebra. In the model, an aspect is specified as an extended architecture model, in which aspect components encapsulate the function of the aspect while aspect connectors encapsulate the weaving logics of the aspect. The separation of weaving logics can promote reuse. Then, we give a formal definition for aspect weaving. The definition builds the structural and behavioral relationship between the woven and wove models, which lays foundations for future semantic analysis and reasoning. An example illustrates the notions and models.