Spring-13 AOP 动态通知 & 静态通知

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本章会介绍 AOP 静态通知 和 动态通知, 静态通知很简单是指固定的表达式在编译器就已经确定了，动态通知 的表达式是在每次调用时动态的最终确定的。

场景

public class AopTest {

    @Aspect
    static class MyAspect {

        // 静态通知
        @Before("execution(* foo(..))")
        public void before1() {
            System.out.println("@Aspect @Before1 ------------------------------");
        }

        // 动态通知
        @Before("execution(* foo(..)) && args(x)")
        public void before2(int x) {
            System.out.println("@Aspect @Before2 ------------------------------ x = " + x);
        }

    }

    static class Target {
        public void foo(int x) {
            System.out.println("Target foo x = " + x);
        }
    }

    public static void main(String[] args) throws Throwable {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        Logger logger = loggerContext.getLogger(AnnotationAwareAspectJAutoProxyCreator.class);
        logger.setLevel(Level.TRACE);

        DefaultListableBeanFactory factory = new DefaultListableBeanFactory();

        AnnotationAwareAspectJAutoProxyCreator proxyCreator = new AnnotationAwareAspectJAutoProxyCreator();
        proxyCreator.setBeanFactory(factory);
        factory.addBeanPostProcessor(proxyCreator);

        factory.registerBeanDefinition("myAspect" , BeanDefinitionBuilder
                .genericBeanDefinition(MyAspect.class)
                .getBeanDefinition());

        // findEligibleAdvisors
        Method findEligibleAdvisors = AbstractAdvisorAutoProxyCreator.class.getDeclaredMethod("findEligibleAdvisors", Class.class, String.class);
        findEligibleAdvisors.setAccessible(true);
        List<Advisor> advisors = (List<Advisor>) findEligibleAdvisors.invoke(proxyCreator, Target.class, "target");
        for (Advisor advisor : advisors) {
            System.out.println("advisor => " + advisor);
        }



        Target target = new Target();
        ProxyFactory proxyFactory = new ProxyFactory();
        proxyFactory.addAdvisors(advisors);
        proxyFactory.setTargetClass(Target.class);
        proxyFactory.setTargetSource(new SingletonTargetSource(target));

        Object proxy = proxyFactory.getProxy();

        List<Object> chain = proxyFactory.getInterceptorsAndDynamicInterceptionAdvice(Target.class.getDeclaredMethod("foo" , int.class), Target.class);
        for (Object c : chain) {
            System.out.println(">>>>>>>>>>>>>>>>>>>>>>>>> " + c);
        }

        Constructor<ReflectiveMethodInvocation> constructor = ReflectiveMethodInvocation.class.getDeclaredConstructor(Object.class, Object.class, Method.class, Object[].class, Class.class, List.class);
        constructor.setAccessible(true);
        ReflectiveMethodInvocation invocation = constructor.newInstance(proxy , target ,
                Target.class.getDeclaredMethod("foo" , int.class) , new Object[]{666} , Target.class , chain);
        invocation.proceed();
    }

}

动态通知 InterceptorAndDynamicMethodMatcher

确定动态通知

DefaultAdvisorChainFactory#getInterceptorsAndDynamicInterceptionAdvice 方法内会根据 MethodMatcher 判断切面是否为动态通知。

ReflectiveMethodInvocation#proceed

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