Nicolas Pessemier

A model for developing component-based and aspect-oriented systems

Aspect-Oriented Programming (AOP) and Component- Based Software Engineering (CBSE) offer solutions to improve the separation of concerns and to enhance a program structure. If the integration of AOP into CBSE has already been proposed, none of these solutions focus on the application of CBSE principles to AOP. In this paper we propose a twofold integration of AOP and CBSE. We introduce a general model for components and aspects, named Fractal Aspect Component (FAC). FAC decomposes a software system into regular components and aspect components (ACs), where an AC is a regular component that embodies a crosscutting concern. We reify the aspect domain of an AC and the relationship between an AC and a component, called an aspect binding, as first-class runtime entities. This clarifies the architecture of a system where components and aspects coexist. The system can evolve from the design to the execution by adding or removing components, aspects or bindings.

A component-based and aspect-oriented model for software evolution

Component-Based Software Development (CBSD) and Aspect Oriented Software Development (AOSD) are solutions to support software evolution by decomposing a software system into concerns. In this paper, we propose Fractal Aspect Component (FAC), a general and symmetrical model for components and aspects. FAC decomposes a software system into regular components and aspect components which embody crosscutting concerns. We reify the relationship between an aspect component and a component, called an aspect binding, as a first-class runtime entity. The evolution of the system can be expressed by adding or removing components (aspect or regular) and by setting bindings (regular or crosscutting).

A component model engineered with components and aspects

This paper presents AOKell, a framework for engineering component-based systems. This framework implements the Fractal model, a hierarchical and dynamic component model. The novelty of this paper lies in the presentation of AOKell, an implementation of the Fractal model with aspects. Two dimensions can be isolated with Fractal: the functional dimension, which is concerned with the definition of application components, and the control dimension, which is concerned with the technical services (e.g. lifecycle, binding, persistence, etc.) that manage components. The originality of AOKell is, first, to provide an aspect-oriented approach to integrate these two dimensions, and second, to apply a component-based approach for engineering the control dimension. Hence, AOKell is a reflective component framework where application components are managed by other, so-called, control components and where aspects glue together application components and control components.