Question

我有注释@Validatable，我希望拦截对该方法的所有调用，返回int。对于intsance：

@Validatable
public int method(){
   //...
}

如何编写pointcut来做到这一点？一般来说，我需要编写以下方面：

public aspect ValidateAspect {
    pointcut publicMethodExecuted(): execution(__HERE_SHOULD_BE_THE_PATTERN__);

    int around() : publicMethodExecuted() {
        //performing some validation and changing return value
    }
}

Answer 1

使用以下代码获取属于int method()方法的注释后，您可以执行所需的操作：

pointcut publicMethodExecuted(): execution(public int <classname>.method());
int around() : publicMethodExecuted() {
  //performing some validation and changing return value
  MethodSignature signature = (MethodSignature) thisJoinPoint.getSignature();
  String methodName = signature.getMethod().getName();
  Annotation[] annotations = thisJoinPoint.getThis().getClass().getDeclaredMethod(methodName).getAnnotations();
  for (Annotation annotation : annotations)
      System.out.println(annotation);
 }

Answer 2

AspectJ支持非常简单的PointCut Designators用于带注释的方法。对于您的用例，它是：

public aspect ValidateAspect {
    pointcut publicMethodExecuted(): @annotation(Validatable);

    int around() : publicMethodExecuted() {
        //performing some validation and changing return value
    }
}

如何拦截@Validatable注释的所有方法

2 个答案: