| [aspectj-users] Around advice and return type |
| Ok, around advice and return type matching that uses + notation does not really work for decorating or proxy-ing objects. Since the class hierarchy I would like to decorate using an aspect is fairly small, I decided to go with the following solution: public abstract aspect Base<T> { pointcut matchGetA() : call(T *.*(..)); T around() : matchGetA() { T result = proceed(); ... return result; } static aspect BaseA extends Base<A> {}; static aspect BaseB extends Base<B> {}; static aspect BaseC extends Base<C> {}; } where B and C derive from A. Adam > Hi all, > > This is probably a beginner question. > In the following code snippet I would like to > catch all calls to methods that return an instance of class A > and all derived classes, do some operations on the object > and return it back. > > @Pointcut("call(A+ *.*(..))") > void matchGetA() {}; > > @Around("matchGetA()") > public A processA(ProceedingJoinPoint thisJoinPoint) { > try { > A result = (A)thisJoinPoint.proceed(); > ... > return result; > } catch (Throwable e) { > throw new Exception(e); > } > } > > This snippet does not compile when I have a method > public B getB() {} > and B is derived from A. > > The only option I can think of is to set the return type of processA () advice to Object. > Does a better (more type save) method exist to build this kind of advices. > > Thanks, > Adam |