I have a question on how to swap the class? At the moment I have an existing class ClassA.foo, and I want this to use a different class instead ClassB to do a different implementation of the call (I am not using interfaces). I am not very familiar with AspectJ, but this concept is working of AspectJ, that is, it automatically swaps the class with pattern similar to the ClassA name and packaging. However for Spring, it seems like I couldnt find a way to automatically allow the his. I still have to use an interface first to specify in the context xml the advisors, and I have to use the application context xml.