Pointcut

Abstract: In aspect-oriented programming, pointcuts are used to describe crosscutting structure. Pointcuts that abstract over irrelevant implementation details are clearly desired to better support maintainability and modular reasoning. We present an analysis which shows that current pointcut languages support localization of crosscutting concerns but are problematic with respect to information hiding. To cope with the problem, we present a pointcut language that exploits information from different models of program semantics, such as the execution trace, the syntax tree, the heap, static type system, etc., and supports ion mechanisms analogous to functional abstraction. We show how this raises the abstraction level and modularity of pointcuts and present first steps toward an efficient implementation by means of a static analysis technique.

Abstract: AspectS is an approach to general-purpose aspect-oriented programming in the Squeak/Smalltalk environment. Based on concepts of AspectJ it extends the Smalltalk metaobject protocol to accommodate the aspect modularity mechanism. In contrast to systems like AspectJ, weaving and unweaving in AspectS happens dynamically at runtime, on-demand, employing metaobject composition. Instead of introducing new language constructs, AspectS utilizes Smalltalk itself as its pointcut language. AspectS benefits from the expressiveness of Smalltalk, its elegance and power.

Abstract: Distribution-related concerns, such as data replication, often crosscut the business code of a distributed application. Currently such crosscutting concerns are frequently realized on top of distributed frameworks, such as EJBs, and initial AO support for the modularization of such crosscutting concerns, e.g., JBoss AOP and Spring AOP, has been proposed.Based on an investigation of the implementation of replicated caches using JBoss Cache, we motivate that crosscutting concerns of distributed applications benefit from an aspect language for explicit distributed programming. We propose AWED, a new aspect language with explicit distributed programming mechanisms, which provides three contributions. First, remote pointcut constructors which are more general than those of previous related approaches, in particular, supporting remote sequences. Second, a notion of distributed advice with support for asynchronous and synchronous execution. Third, a notion of distributed aspects including models for the deployment, instantiation and state sharing of aspects. We show several concrete examples how AWED can be used to modularly implement and extend replicated cache implementations. Finally, we present a prototype implementation of AWED, which we have realized by extending JAsCo, a system providing dynamic aspects for Java.

Abstract: A dataflow-based pointcut is proposed for aspect-oriented programming (AOP) languages. The pointcut specifies where aspects should be applied based on the origins of values. It is designed to be compatible with the other kinds of pointcuts in existing AOP languages. Primary application fields of the pointcut are the aspects in which flow of information is important, such as security. This paper presents the design of the pointcut with a web-application example, and its prototype implementation.