Spring AOP - why do i need aspectjweaver?

Question

i wrote a very simple Aspect with Spring AOP. It works, but i have some problems understanding what is really going on. I don't understand why i have to add the aspectjweaver.jar? The Spring-AOP documentation clearly states that i don't need aspectj compiler or weaver as long as i just use Spring-AOP:

The AOP runtime is still pure Spring AOP though, and there is no dependency on the AspectJ compiler or weaver.

My configuration looks like this:

<aop:aspectj-autoproxy />

@Aspect
@Service
public class RemoteInvocationAspect {

    @Before("execution(* at.test.mypackage.*.*(..))")
    public void test() {
        System.out.println("test");
    }
    ...

I also tried XML configuration, didn't change anything though. Maybe i could just let it go, but i really would like to understand why aspectj-weaver is used? If i don't add the dependency in maven i get java.lang.ClassNotFoundException: org.aspectj.weaver.reflect.ReflectionWorld$ReflectionWorldException

Answer 1

Spring AOP implementation I think is reusing some classes from the aspectj-weaver. It still uses dynamic proxies - doesn't do byte code modification.

The following comment from the spring forum might clarify.

Spring isn't using the AspectJ weaver in this case. It is simply reusing some of the classes from aspectjweaver.jar.

-Ramnivas