Aspect IX A Middleware for Aspect-Oriented Programming

Abstract

Abstract:Object-based middleware systems, like CORBA, provide the basis for object-based distributed applications. For aspects concerning distributed programming an aspect weaver has to generate code which interacts with the middleware system. As parts of these aspects often have to be implemented on top of the middleware, weavers are very dependent on the middleware system and on the implementations on top of it. This paper introduces a middleware called AspectIX that provides aspects as a generic mechanism to implement and control nonfunctional properties of a distributed object (e.g., properties related to the communication mechanisms used for a distributed object or the consistency policies between replicated data parts of the distributed objects). AspectIX provides an open and generic interface to all of these nonfunctional aspects. Aspect configuration can be controlled and changed at run-time with an immediate effect on the distributed object.The AspectIX architecture allows implementations of a distributed AspectIX object to be dynamically replaced in order to fulfill a new aspect configuration. Thus, an AspectIX implementation is also open for new aspects.

THAOP: An Aspect Oriented Programming Framework

“…The JAC (Java Aspect Components) project [10] provides a framework to build aspect-oriented distributed applications in Java. The AspectlX project [11] provides a middleware that provides aspects as a generic mechanism to implement and control non-functional properties of a distributed object (e.g., properties related to the communication mechanisms used for a distributed object or the consistency policies between replicated data parts of the distributed objects). Aspect configuration can be controlled and changed at run-time with an immediate effect on the distributed object.…”

Enabling collaborative adaptation across legacy components

“…Many others place adaptive behavior in middleware which, in addition to its traditional role in hiding resource distribution and platform heterogeneity, can be used to address concerns such as quality-of-service, energy management, fault tolerance, and security policy. Examples include Iguana/J [3], TAO [4], DynamicTAO [5], Open ORB [6], QuO [7], ORBacus [8], Squirrel [9], IRL [10], AspectIX [11], and ACT [12]. Finally, several projects focus on dynamic recomposition within the application itself, either directly by using a language that supports recomposition (e.g., CLOS or Python) or indirectly by modifying code as it is loaded by a virtual machine (as in Kava), or dynamically weaving new behavior into running programs (e.g., Iguana/J, TRAP/J, DADO, ABASCO, and Reflex.…”

A Middleware Architecture for Scalable, QoS-Aware, and Self-Organizing Global Services

“…In AspectIX, a distributed object is partitioned into fragments [5]. Clients need a local fragment to invoke methods at a distributed object.…”

“…As the developer knows that the service may have millions of users, he has to take care of scalability. Thus, he provides two additional fragment implementations: a replicating and a caching fragment 5 . The caching fragment has the same functionality as the stub fragment, but can store query results in a local cache.…”

“…4 This is especially interesting if only some of the application objects need to be truly partitioned, e.g., if a legacy application is ported to AspectIX. 5 Instead of hand-coding the replicating fragment, the replication framework of Globe [26] or BOAR [12] could be used to create it. Stub and cache fragments can contact either a server or a replica.…”