aspect-oriented programming

programming (AOP) A style of programming that attempts to

abstract out features common to many parts of the code beyond

simple functional modules and thereby improve the quality of

software.

Mechanisms for defining and composing abstractions are

essential elements of programming languages. The design style

supported by the abstraction mechanisms of most current

languages is one of breaking a system down into parameterised

components that can be called upon to perform a function.

But many systems have properties that don't necessarily align

with the system's functional components, such as failure

handling, persistence, communication, replication,

coordination, memory management, or real-time constraints,

and tend to cut across groups of functional components.

While they can be thought about and analysed relatively

separately from the basic functionality, programming them

using current component-oriented languages tends to result

in these aspects being spread throughout the code. The

source code becomes a tangled mess of instructions for

different purposes.

This "tangling" phenomenon is at the heart of much needless

complexity in existing software systems. A number of

researchers have begun working on approaches to this problem

that allow programmers to express each of a system's aspects

of concern in a separate and natural form, and then

automatically combine those separate descriptions into a final

executable form. These approaches have been called

aspect-oriented programming.

Xerox AOP homepage.

AspectJ .

ECOOPP'99 AOP workshop.

(1999-11-21)