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Abstract. J2EE is a middleware architecture augmented with supporting tools for developing large scale client/server and multi-tier applications. J2EE uses En-terprise JavaBeans as its component model. The realization of these componentsby a J2EE application server can be conceptually decomposed into distinct as-pects such as persistence, transaction management, security, and load balancing.However, current servers do not employ aspect-oriented programming in theirimplementation. In this paper, we describe a new aspect language, AspectJ2EE,geared towards the generalized implementation of J2EE application servers, andapplications within this framework. AspectJ2EE can be easily employed to ex-tend the fixed set of services that these servers provide with new services such aslogging and performance monitoring. Even tier-cutting concerns like encryption,data compression, and memoization can be added while avoiding the drags ofcross-cutting and scattered code.AspectJ2EE is less general (and hence less complicated) than AspectJ, yetdemonstrably powerful enough for the systematic development of large scale(and distributed) applications. The introduction of parameterized aspects makesaspects in AspectJ2EE more flexible and reusable than aspects in AspectJ.AspectJ2EE also generalizes the process of binding services to user applicationsin the application server into a novel deploy-time weaving of aspects. Deploy-time weaving is superior to traditional weaving mechanisms, in that it preservesthe object model, has a better management of aspect scope, and presents a moreunderstandable and maintainable semantic model.