Spring AOP 实现

public BeanDefinition parse(Element element, ParserContext parserContext) {
    CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(element.getTagName(), parserContext.extractSource(element));
    parserContext.pushContainingComponent(compositeDef);
 this.configureAutoProxyCreator(parserContext, element);
    List childElts = DomUtils.getChildElements(element);
    Iterator var5 = childElts.iterator();

    while(var5.hasNext()) {
        Element elt = (Element)var5.next();
        String localName = parserContext.getDelegate().getLocalName(elt);
        if("pointcut".equals(localName)) {
            this.parsePointcut(elt, parserContext);
        } else if("advisor".equals(localName)) {
            this.parseAdvisor(elt, parserContext);
        } else if("aspect".equals(localName)) {
            this.parseAspect(elt, parserContext);
        }
    }

    parserContext.popAndRegisterContainingComponent();
    return null;
}

public static BeanDefinition registerAspectJAutoProxyCreatorIfNecessary(BeanDefinitionRegistry registry, Object source) {
return registerOrEscalateApcAsRequired(AspectJAwareAdvisorAutoProxyCreator.class, registry, source);
}

public BeanDefinition parse(Element element, ParserContext parserContext) {
 AopNamespaceUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(parserContext, element);
    this.extendBeanDefinition(element, parserContext);
    return null;
}
public static BeanDefinition registerAspectJAnnotationAutoProxyCreatorIfNecessary(BeanDefinitionRegistry registry, Object source) {
return registerOrEscalateApcAsRequired(AnnotationAwareAspectJAutoProxyCreator.class, registry, source);
}

public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException { if(bean != null) { Object cacheKey = this.getCacheKey(bean.getClass(), beanName); if(!this.earlyProxyReferences.contains(cacheKey)) { return this.wrapIfNecessary(bean, beanName, cacheKey); } } return bean; }

public AopProxy createAopProxy(AdvisedSupport config) throws AopConfigException {
if(!config.isOptimize() && !config.isProxyTargetClass() && !this.hasNoUserSuppliedProxyInterfaces(config)) {
return new JdkDynamicAopProxy(config);
} else {
        Class targetClass = config.getTargetClass();
        if(targetClass == null) {
throw new AopConfigException("TargetSource cannot determine target class: Either an interface or a target is required for proxy creation.");
} else {
return (AopProxy)(targetClass.isInterface()?new JdkDynamicAopProxy(config):new ObjenesisCglibAopProxy(config));
}
    }
}

public Object getProxy(ClassLoader classLoader) {
if(logger.isDebugEnabled()) {
        logger.debug("Creating JDK dynamic proxy: target source is " + this.advised.getTargetSource());
}

    Class[] proxiedInterfaces = AopProxyUtils.completeProxiedInterfaces(this.advised);
    this.findDefinedEqualsAndHashCodeMethods(proxiedInterfaces);
    return Proxy.newProxyInstance(classLoader, proxiedInterfaces, this);
}

public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
    Object oldProxy = null;
    boolean setProxyContext = false;
TargetSource targetSource = this.advised.targetSource;
Class targetClass = null;
Object target = null;

Object retVal;
    try {
      //eqauls()方法，具目标对象未实现此方法 
if(!this.equalsDefined && AopUtils.isEqualsMethod(method)) {
            Boolean retVal2 = Boolean.valueOf(this.equals(args[0]));
            return retVal2;
}
 //hashCode()方法，具目标对象未实现此方法  
if(!this.hashCodeDefined && AopUtils.isHashCodeMethod(method)) {
            Integer retVal1 = Integer.valueOf(this.hashCode());
            return retVal1;
}
 //Advised接口或其父接口中定义的方法,直接反射调用,不利用通知  
if(this.advised.opaque || !method.getDeclaringClass().isInterface() || !method.getDeclaringClass().isAssignableFrom(Advised.class)) {
if(this.advised.exposeProxy) {
                oldProxy = AopContext.setCurrentProxy(proxy);
setProxyContext = true;
}
 //取得目标对象的类  
            target = targetSource.getTarget();
            if(target != null) {
                targetClass = target.getClass();
}
 //获得可以利用到此方法上的Interceptor列表  List chain = this.advised.getInterceptorsAndDynamicInterceptionAdvice(method, targetClass); if(chain.isEmpty()) {   //如果没有可以利用到此方法的通知(Interceptor)，此直接反射调用 method.invoke(target, args) 
                retVal = AopUtils.invokeJoinpointUsingReflection(target, method, args);
} else {
           //创建MethodInvocation ，封装 Interceptor调用链

 ReflectiveMethodInvocation invocation = new ReflectiveMethodInvocation(proxy, target, method, args, targetClass, chain);
         //调用proceed()方法， 顺次履行 Interceptor调用链 retVal = invocation.proceed(); }

            Class returnType = method.getReturnType();
            if(retVal != null && retVal == target && returnType.isInstance(proxy) && !RawTargetAccess.class.isAssignableFrom(method.getDeclaringClass())) {
                retVal = proxy;
} else if(retVal == null && returnType != Void.TYPE && returnType.isPrimitive()) {
throw new AopInvocationException("Null return value from advice does not match primitive return type for: " + method);
}

            Object var13 = retVal;
            return var13;
}

        retVal = AopUtils.invokeJoinpointUsingReflection(this.advised, method, args);
} finally {
if(target != null && !targetSource.isStatic()) {
            targetSource.releaseTarget(target);
}

if(setProxyContext) {
            AopContext.setCurrentProxy(oldProxy);
}

    }

return retVal;
}

通过this.advised.getInterceptorsAndDynamicInterceptionAdvice(method, targetClass)方法，获得通知拦截器链

public class DefaultAdvisorAdapterRegistry implements AdvisorAdapterRegistry, Serializable { private final Listadapters = new ArrayList(3); public DefaultAdvisorAdapterRegistry() { this.registerAdvisorAdapter(new MethodBeforeAdviceAdapter()); this.registerAdvisorAdapter(new AfterReturningAdviceAdapter()); this.registerAdvisorAdapter(new ThrowsAdviceAdapter()); } public Advisor wrap(Object adviceObject) throws UnknownAdviceTypeException { if(adviceObject instanceof Advisor) { return (Advisor)adviceObject; } else if(!(adviceObject instanceof Advice)) { throw new UnknownAdviceTypeException(adviceObject); } else { Advice advice = (Advice)adviceObject; if(advice instanceof MethodInterceptor) { return new DefaultPointcutAdvisor(advice); } else { Iterator var3 = this.adapters.iterator(); AdvisorAdapter adapter; do { if(!var3.hasNext()) { throw new UnknownAdviceTypeException(advice); } adapter = (AdvisorAdapter)var3.next(); } while(!adapter.supportsAdvice(advice)); return new DefaultPointcutAdvisor(advice); } } } public MethodInterceptor[] getInterceptors(Advisor advisor) throws UnknownAdviceTypeException { ArrayList interceptors = new ArrayList(3); Advice advice = advisor.getAdvice(); if(advice instanceof MethodInterceptor) { interceptors.add((MethodInterceptor)advice); } Iterator var4 = this.adapters.iterator(); while(var4.hasNext()) { AdvisorAdapter adapter = (AdvisorAdapter)var4.next(); if(adapter.supportsAdvice(advice)) { interceptors.add(adapter.getInterceptor(advisor)); } } if(interceptors.isEmpty()) { throw new UnknownAdviceTypeException(advisor.getAdvice()); } else { return (MethodInterceptor[])interceptors.toArray(new MethodInterceptor[interceptors.size()]); } } public void registerAdvisorAdapter(AdvisorAdapter adapter) { this.adapters.add(adapter); } }