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javaspringannotationsaspectjaspect

Spring AspectJ get method annotation from ProceedingJoinPoint


I have an aspect that handles all methods that have a custom annotation.

The annotation has an enum parameter and I have to get the value in the aspect:

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface Monitored {
    MonitorSystem monitorSystem();
}

My case is very similar to that question and the accepted answer works for Spring beans that do not implement an interface.

The aspect:

@Aspect
@Component
public class MonitorAspect {

    @Around("@annotation(com.company.project.monitor.aspect.Monitored)")
    public Object monitor(ProceedingJoinPoint pjp) throws Throwable {
        MethodSignature signature = (MethodSignature) pjp.getSignature();
        MonitorSystem monitorSystem = signature.getMethod().getAnnotation(Monitored.class).monitorSystem();
        ...
    }
}

But if the Spring bean that is annotated with @Monitored (only the implementation class is annotated) implements an interface - pjp.getSignature() returns the signature of the interface and it does not have an annotation.

This is OK:

@Component
public class SomeBean {
   @Monitored(monitorSystem=MonitorSystem.ABC) 
   public String someMethod(String name){}
}

This does not work - pjp.getSignature() gets the signature of the interface.

@Component
public class SomeBeanImpl implements SomeBeanInterface {
   @Monitored(monitorSystem=MonitorSystem.ABC) 
   public String someMethod(String name){}
}

Is there a way to get the signature of the implementation method from ProceedingJoinPoint?


Solution

  • Managed to do it with:

    @Aspect
    @Component
    public class MonitorAspect {
    
        @Around("@annotation(com.company.project.monitor.aspect.Monitored)")
        public Object monitor(ProceedingJoinPoint pjp) throws Throwable {
            MethodSignature signature = (MethodSignature) pjp.getSignature();
            Method method = pjp.getTarget()
               .getClass()
               .getMethod(signature.getMethod().getName(),     
                          signature.getMethod().getParameterTypes());
            Monitored monitored = method.getAnnotation(Monitored.class);
            ...
        }
    }