A Selective, Just-in-Time Aspect Weaver

Dynamic AOP (Aspect-Oriented Programming) is receiving growing interests in both the academia and the industry. Since it allows weaving aspects with a program at runtime, it is useful for rapid prototyping and adaptive software. However, the previous implementations of dynamic AOP systems suffered from serious performance penalties. This paper presents our new efficient dynamic AOP system in Java for addressing the underlying problem. This system called Wool is a hybrid of two approaches. When a new aspect is woven in, the programmers can select to reload into the JVM a modified class file in which hooks for executing advice are statically embedded, or they can insert hooks as breakpoints in the JVM. Since the two approaches have different performance characteristics, the programmers can select the best one for each join point. Our experimental result shows, under a certain circumstance, Wool runs dynamic AOP application about 26% faster than a traditional static code translation approach.