Cannot get aspect to work with java.lang.reflect.Method in signature

[spitbag]

Hi,

I'd appreciate any help with a problem I'm having with an aspect. I've read the Spring documentation and Spring In Action but I still cannot see what I'm doing wrong!

Basically, I've an after-throwing aspect configured using the AOP tags. The aspect works fine when my method just takes a Throwable object.
But I need access to java.lang.reflect.Method as my aspect needs to find out the return type from my Business Layer.
So when my aspect's method takes ([Method], [args], [target], Throwable) it just does not work. What configuration am I missing here?

(Would post my code config but don't have access to it today)

Thanks

[spitbag]

This is my application context:

<aop:config proxy-target-class="true">
       		<aop:aspect ref="serviceExceptionAspect">
       			<aop:after-throwing 
       			method="catchThrowable"
       			pointcut="execution(* com.application.business.impl.*.*(..)) and args(method, args, target)"
       			throwing="ex" />
       		</aop:aspect>
       </aop:config>

And my serviceExceptionAspect method which is never entered:

public Wrapper catchThrowable(Method method, Object[] args, Object target, Throwable ex)
	{

What is wrong with this config? The pointcut works fine if I only have Throwable in the method signature....

[denis.zhdanov]

Am I right assuming that you think that spring aop will automatically match your aspect Method parameter to the method metadata (Method object)?

[spitbag]

You probably are. How is this done so? Thanks.

[denis.zhdanov]

AopService.java

package com.spring.aop;

import org.springframework.stereotype.Component;

@Component
public class AopService {

    public void service() {
        System.out.println("xxxxxxxxxx: AopService.service()");
        throw new IllegalArgumentException("test exception");
    }
}

TestAspect.java

package com.spring.aop;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.reflect.MethodSignature;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class TestAspect {

    @AfterThrowing(pointcut = "execution(* com.spring.aop.AopService.*(..))", throwing = "e")
    public void advice(JoinPoint joinPoint, Throwable e) {
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        System.out.println("xxxxxxxxx: TestAspect.advice(). Return type is " + signature.getReturnType());
    }
}

spring-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:util="http://www.springframework.org/schema/util"
       xsi:schemaLocation="
  http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
  http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
  http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
  http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.5.xsd">

    <context:component-scan base-package="com.spring.aop"/>
    <aop:aspectj-autoproxy proxy-target-class="true"/>

</beans>

SpringStart.java

package com.spring;

import com.spring.aop.AopService;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class SpringStart {
    public static void main(String[] args) throws Exception {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring-config.xml");

        AopService aopService = (AopService)context.getBean("aopService");
        aopService.service();
    }
}

Output:

xxxxxxxxxx: AopService.service()
xxxxxxxxx: TestAspect.advice(). Return type is void
Exception in thread "main" java.lang.IllegalArgumentException: test exception
	at com.spring.aop.AopService.service(AopService.java:10)
	at com.spring.aop.AopService$$FastClassByCGLIB$$a6d02733.invoke(<generated>)
	at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
	at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:700)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
	at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:54)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:89)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
	at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:635)
	at com.spring.aop.AopService$$EnhancerByCGLIB$$e28809a7.service(<generated>)
	at com.spring.SpringStart.main(SpringStart.java:11)

[juk]

You should access the method using the JoinPoint class. Change your method signature from (Method method, Object[] args, Object target, Throwable ex) to (JoinPoint joinPoint, Throwable ex).

[jraven76]

Denis and Juk - thank you so much for replying to this question. I have been searching for the solution to this exact problem all day! You saved me a lot of time of experimenting.