Get annotated parameters inside a pointcut

问题

I have two annotation @LookAtThisMethod and @LookAtThisParameter, if I have a pointcut around the methods with @LookAtThisMethod how could I extract the parameters of said method which are annotated with @LookAtThisParameter?

For example:

@Aspect
public class LookAdvisor {

    @Pointcut("@annotation(lookAtThisMethod)")
    public void lookAtThisMethodPointcut(LookAtThisMethod lookAtThisMethod){}

    @Around("lookAtThisMethodPointcut(lookAtThisMethod)")
    public void lookAtThisMethod(ProceedingJoinPoint joinPoint, LookAtThisMethod lookAtThisMethod) throws Throwable {
        for(Object argument : joinPoint.getArgs()) {
            //I can get the parameter values here
        }

        //I can get the method signature with:
        joinPoint.getSignature.toString();


        //How do I get which parameters  are annotated with @LookAtThisParameter?
    }

}

回答1:

I modeled my solution around this other answer to a different but similar question.

MethodSignature signature = (MethodSignature) joinPoint.getSignature();
String methodName = signature.getMethod().getName();
Class<?>[] parameterTypes = signature.getMethod().getParameterTypes();
Annotation[][] annotations = joinPoint.getTarget().getClass().getMethod(methodName,parameterTypes).getParameterAnnotations();

The reason that I had to go through the target class was because the class that was annotated was an implementation of an interface and thusly signature.getMethod().getParameterAnnotations() returned null.

回答2:

final String methodName = joinPoint.getSignature().getName();
    final MethodSignature methodSignature = (MethodSignature) joinPoint
            .getSignature();
    Method method = methodSignature.getMethod();
    GuiAudit annotation = null;
    if (method.getDeclaringClass().isInterface()) {
        method = joinPoint.getTarget().getClass()
                .getDeclaredMethod(methodName, method.getParameterTypes());
        annotation = method.getAnnotation(GuiAudit.class);
    }

This code covers the case where the Method belongs to the interface

来源：https://stackoverflow.com/questions/6604428/get-annotated-parameters-inside-a-pointcut

标签

java

annotations

aop

aspectj