Towards aspect weaving applications

Abstract

Software must be adapted to accommodate new features in the context of changing requirements. In this paper, we illustrate how applications with aspect weaving capabilities can be easily and dynamically adapted with unforseen features. Aspects were used at three levels: in the context of semantic analysers, within a BPEL engine that orchestrates Web Services, and finally within BPEL processes themselves. Each level uses its own tailored domain-specific aspect language that is easier to manipulate than a generalpurpose one (close to the programming language) and the pointcuts are independent from the implementation.

Runtime Monitoring CompositeWeb Services Through Stateful Aspect Extension

“…The attributes of an activity can be used as predicates to choose relevant join points [13] . Similar to the work in [5,13], we choose XPath as the pointcut language since WS-BPEL processes are XML-based documents. The set operators XPath provides, such as union operator and intersect operator, can be used to combine pointcuts that select different types of activities.…”

“…Aspect-oriented programming (AOP) offers a new set of language features to increase modularity and separation of concerns, which makes it very suitable for runtime monitoring [5,6] . However, monitoring composite Web services based on AOP technology is not yet adequately supported in existing work.…”

“…However, monitoring composite Web services based on AOP technology is not yet adequately supported in existing work. In most aspect extension to WS-BPEL [5,7,8] , the observation that an aspect can make are confined to the current process state: it is not possible to directly observe the history (or the event trace) of the process execution. "Stateful Aspect" [9,10] , the advanced feature in Aspect-Oriented Software Development (AOSD), is not supported currently, which makes it difficult to express complex monitoring tasks, such as the behavior constraints mentioned above in the OTA process.…”

Architecture pour l'adaptation de systèmes d'information interactifs orientés services

“…La prise en compte de propriétés non-fonctionnelles (sécurité, traçage, cryptographie...) qui enrichissent les services est abordée via différents travaux (Charfi et al, 2004, Courbis et al, 2005a, Courbis et al, 2005b qui s'appuient sur le paradigme de la programmation par aspects (Kiczales et al, 1997, Douence, 2004. L'utilisation de ce paradigme pour modifier les orchestrations est montrée dans les travaux d'Anis Charfi (Charfi et al, 2005b, Charfi et al, 2005a …”

Three applications of aspect technology

“…To address these issues, we have extended a BPEL engine with dynamic aspects [9,10]. This engine prototype makes it possible to plug in and out new behaviours at run time and to modify the structure of running business processes.…”