Spring AOP point cut for 'nested' annotation

Question

I need to define a point cut which triggers the execution on all methods of a spring service annotated with a custom annotation. The annotation I would like to define the po

Answer 1

This is not a Spring or AspectJ problem. In Java, annotations on interfaces, other annotations or methods are never inherited by implementing classes, classes using annotated annotations or overriding methods. Annotation inheritance only works from classes onto subclasses, but only if the annotation type used in the superclass bears the meta annotation @Inherited.

Update: Because I have answered this question several times before, I have just documented the problem and also a workaround in Emulate annotation inheritance for interfaces and methods with AspectJ.

Here is a little proof that what you want does not work and thus also cannot be utilised by an aspect:

package de.scrum_master.app;

import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Inherited
@Retention(RetentionPolicy.RUNTIME)
public @interface OuterAnnotation {}

package de.scrum_master.app;

import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Inherited
@Retention(RetentionPolicy.RUNTIME)
@OuterAnnotation
public @interface InnerAnnotation {}

package de.scrum_master.app;

import java.lang.annotation.Annotation;

@InnerAnnotation
public class Application {
    public static void main(String[] args) {
        for (Annotation annotation : Application.class.getAnnotations())
            System.out.println(annotation);
    }
}

The console output shows that only the inner annotation is seen by the JVM, not the outer one used on the inner annotation:

@de.scrum_master.app.InnerAnnotation()

---

Update: Intrigued by Bradley M Handy's answer, I re-checked if it would also work for the situation described in my code, and indeed it does. Thise type of AspectJ syntax was unknown to me, even though I think I know a lot about AspectJ. So thanks, Bradley. :-) This aspect would work:

package de.scrum_master.aspect;

import de.scrum_master.app.OuterAnnotation;

public aspect MetaAnnotationAspect {
  after() : within(@(@OuterAnnotation *) *) && execution(* *(..)) {
    System.out.println(thisJoinPoint);
  }
}

Console log when running the application:

@de.scrum_master.app.InnerAnnotation()
execution(void de.scrum_master.app.Application.main(String[]))