Question

我想捕获实现 Processor 接口的类抛出的异常。在方面我需要访问处理器，它会抛出异常。我定义了以下切入点：

@Pointcut("target(some.package.Processor) && args(message)")
  public void processor(Message message) {
}

方面：

@AfterThrowing(pointcut="processor(message)", throwing="ex")
public void onExceptionInProcessor(Processor target, Exception ex, Message message) {
  // code skipped
}

但是，我得到以下例外：

Caused by: java.lang.IllegalArgumentException: error at ::0 formal unbound in pointcut 
    at org.aspectj.weaver.tools.PointcutParser.parsePointcutExpression(PointcutParser.java:301) ~[aspectjweaver-1.6.12.jar:1.6.12]
    at org.springframework.aop.aspectj.AspectJExpressionPointcut.buildPointcutExpression(AspectJExpressionPointcut.java:207) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.aspectj.AspectJExpressionPointcut.buildPointcutExpression(AspectJExpressionPointcut.java:193) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.aspectj.AspectJExpressionPointcut.checkReadyToMatch(AspectJExpressionPointcut.java:182) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.aspectj.AspectJExpressionPointcut.getClassFilter(AspectJExpressionPointcut.java:163) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.support.AopUtils.canApply(AopUtils.java:209) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.support.AopUtils.canApply(AopUtils.java:263) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.support.AopUtils.findAdvisorsThatCanApply(AopUtils.java:295) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAdvisorAutoProxyCreator.findAdvisorsThatCanApply(AbstractAdvisorAutoProxyCreator.java:117) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAdvisorAutoProxyCreator.findEligibleAdvisors(AbstractAdvisorAutoProxyCreator.java:87) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAdvisorAutoProxyCreator.getAdvicesAndAdvisorsForBean(AbstractAdvisorAutoProxyCreator.java:68) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:359) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:322) ~[spring-aop-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:407) ~[spring-beans-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1461) ~[spring-beans-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) ~[spring-beans-3.1.0.RELEASE.jar:3.1.0.RELEASE]
    ... 58 common frames omitted

将目标对象绑定到方面的正确方法是什么？我找到的唯一方法是绑定 JoinPoint ，但它建议遵循：

除非您特别需要这种反射访问，否则您应该使用目标切入点指示符获取此对象以获得更好的静态打字和表现

有人如何做到这一点？

Answer 1

您的target应该引用方法中的一个参数名称。例如说

@Pointcut("target(myProc) && args(message)")
public void processor(Processor myProc, Message message) {
}

会在Processor变量中以类型安全的方式为您提供myProc。

Spring AOP：将目标传递给Aspect

1 个答案: