make decisions about an agent property while only
looking at its description and its interface with other
Smooth Transition in Software Life-Cycle Phases.
Aspect-oriented agent architectures are directly
mapped to implementation abstractions using well-known aspect-oriented programming languages, such
as AspectJ [ 1]. AspectJ, which extends the Java programming language, is the most popular aspect language. Architectural aspects are decomposed into a set
of AspectJ aspects and classes. The crosscutting interfaces are realized as pointcuts, advice, and inter-type
declarations, because they define different ways an
aspect affects other design and implementation modules. Join points are well-defined points in the
dynamic execution of the system components. Examples of join points are method calls and method executions. Pointcuts have a name and are collections of
join points. Advice is a special method-like construct
attached to pointcuts. Inter-type declarations introduce attributes, methods, and interface implementation declarations into the components to which the
crosscutting interface is attached. We have implemented an AspectJ framework that supports this
aspect-oriented architectural style at the implementation level [ 5]. It helps to guarantee a smooth transition
from the specification of heterogeneous agent architectures to their detailed design and implementation. We
have also developed several other aspect-oriented techniques to cope with agent aspects in different software
development phases in order to facilitate the traceability of the software engineering artifacts.
Coping with Dynamic Adaptability and Cus-tomizability. Architecting software agents with
improved separation of concerns is of paramount
importance in open, dynamic agent-based systems.
Dynamic reconfiguration of agent roles and collaboration protocols are often required as the agents move to
different environments. In addition, with the growing
number of applications for pervasive computing, the
selection of learning and coordination strategies may
depend on the context in which the agent is being executed. As such, agent architectures need to be designed
properly, and the dependency inversion gained with
aspect-oriented agent architectures is a key factor to
allow the agent adaptation and customization.
Numerous types of agent architectures are prevalent
[ 8] and must be developed in a way that meets the
stringent modern requirements of evolvability,
reusability, and dynamic reconfigurability. Existing
architectural styles are rigid by their very nature and
unable to cope with the crosscutting nature of agent
properties as well as the complexity of heterogeneous
agent architectures, which are often required in realistic modern systems. On the other hand, aspect-oriented software development is gaining wide
attention both in research environments and in
industry as a paradigm to promote improved modularity of complex software systems. The exploration
of aspect-oriented techniques clearly seems a promising step forward to allow the construction of more
flexible agent architectures and to foster enhanced
quality of realistic multi-agent systems. c
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ALESSANDRO GARCIA ( firstname.lastname@example.org) is a lecturer of
computer science at Lancaster University, U.K.
CARLOS LUCENA ( email@example.com) is a professor of computer
science at Pontifical Catholic University of Rio de Janeiro, Rio de
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