A Component-Based and Aspect-Oriented Model for Software Evolution

International audienceComponent-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 article, 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)

On the footprints of join points : the blueprint approach

Aspect-oriented techniques are widely used to better modularize object-oriented programs by introducing crosscutting concerns in a safe and non-invasive way, i.e., aspectoriented mechanisms better address the modularization of functionality that orthogonally crosscuts the implementation of the application. Unfortunately, as noted by several researchers, most of the current aspect-oriented approaches are too coupled with the application code, and this fact hinders the concerns separability and consequently their re-usability since each aspect is strictly tailored on the base application. Moreover, the join points (i.e., locations affected by a crosscutting concerns) actually are defined at the operation level. It implies that the possible set of join points includes every operation (e.g., method invocations) that the system performs. Whereas, in many contexts we wish to define aspects that are expected to work at the statement level, i.e., by considering as a join point every point between two generic statements (i.e., lines of code). In this paper, we present our approach, called Blueprint, to overcome the abovementioned limitations of the current aspect-oriented approaches. The Blueprint consists of a new aspect-oriented programming language based on modeling the join point selection mechanism at a high-level of abstraction to decouple aspects from the application code. To this regard, we adopt a high-level pattern-based join point model, where join points are described by join point blueprints, i.e., behavioral patterns describing where the join points should be found

μ-DSU:A Micro-Language Based Approach to Dynamic Software Updating

Today software systems play a critical role in society’s infrastructures and many are required to provide uninterrupted services in their constantly changing environments. As the problem domain and the operational context of such software changes, the software itself must be updated accordingly. In this paper we propose to support dynamic software updating through language semantic adaptation; this is done through use of micro-languages that confine the effect of the introduced change to specific application features. Micro-languages provide a logical layer over a programming language and associate an application feature with the portion of the programming language used to implement it. Thus, they permit to update the application feature by updating the underlying programming constructs without affecting the behaviour of the other application features. Such a linguistic approach provides the benefit of easy addition/removal of application features (with a special focus on non-functional features) to/from a running application by separating the implementation of the new feature from the original application, allowing for the application to remain unaware of any extensions. The feasibility of this approach is demonstrated with two studies; its benefits and drawbacks are also analysed

Impact-Analyse für AspectJ - Eine kritische Analyse mit werkzeuggestütztem Ansatz

Aspect-Oriented Programming (AOP) has been promoted as a solution for modularization problems known as the tyranny of the dominant decomposition in literature. However, when analyzing AOP languages it can be doubted that uncontrolled AOP is indeed a silver bullet. The contributions of the work presented in this thesis are twofold. First, we critically analyze AOP language constructs and their effects on program semantics to sensitize programmers and researchers to resulting problems. We further demonstrate that AOP—as available in AspectJ and similar languages—can easily result in less understandable, less evolvable, and thus error prone code—quite opposite to its claims. Second, we examine how tools relying on both static and dynamic program analysis can help to detect problematical usage of aspect-oriented constructs. We propose to use change impact analysis techniques to both automatically determine the impact of aspects and to deal with AOP system evolution. We further introduce an analysis technique to detect potential semantical issues related to undefined advice precedence. The thesis concludes with an overview of available open source AspectJ systems and an assessment of aspect-oriented programming considering both fundamentals of software engineering and the contents of this thesis

First-class features

Magdeburg, Univ., Fak. für Informatik, Diss., 2011von Sagar Sunkl