主要内容SpringBoot是如何将AOP相关的类注入到BeanFactory中的，它是如何工作的？总结AopAutoConfiguration：自动注入AOP相关的配置类；AnnotationAwareAspectJAutoProxyCreator；populateBean时，每个bean都会扫描是否有section，并进行匹配；AnnotationAwareAspectJAutoProxyCreator.postProcessAfterInitialization;如果匹配成功，将通过cglib动态代理生成一个新的代理类；具体源码流程1.1自动配置类加载AOP相关类；加载AopAutoConfiguration时，加载CglibAutoProxyFactory时，有一个注解@EnableAspectJAutoProxy，有一个@Import注解，AspectJAutoProxyRegistrar；这个注册商很重要！！!其在ConfigurationClassPostProcessor类扫描加载bean的时候，处理loadBeanDefinitionsFromRegistrars的时候；加载进去；publicvoidregisterBeanDefinitions(AnnotationMetadataimportingClassMetadata,BeanDefinitionRegistryregistry){AopConfigUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(registry);.....registerAspectJAnnotationAutoProxyCreatorIfNecessary()的时候，把AnnotationAwareAspectJAutoProxyCreator封装BeanDefinition，对应key=internalAutoProxyCreator；@NullablepublicstaticBeanDefinitionregisterAspectJAnnotationAutoProxyCreatorIfNecessary(BeanDefinitionRegistryregistry,@NullableObjectsource){//将AnnotationAwareAspectJAutoProxyCreator封装成一个BeanDefinition；返回registerOrEscalateApcAsRequired(AnnotationAwareAspectJAutoProxyCreator.class,registry,source);调用所有BeanPostProcessor.postProcessAfterInitialization；其中，会调用AnnotationAwareAspectJAutoProxyCreator；检查是否有符合要求的切面方法；调用方法如下：protectedObjectwrapIfNecessary(Objectbean,StringbeanName,ObjectcacheKey){...//重点如下：找到这个bean的所有切面方法，然后调用createProxy创建代理类；只是返回。//如果我们有建议，则创建代理。Object[]specificInterceptors=getAdvicesAndAdvisorsForBean(bean.getClass(),beanName,null);if(specificInterceptors!=DO_NOT_PROXY){this.advisedBeans.put(cacheKey,Boolean.TRUE);Objectproxy=createProxy(bean.getClass(),beanName,specificInterceptors,newSingletonTargetSource(bean));this.proxyTypes.put(cacheKey,proxy.getClass());返回代理；}this.advisedBeans.put(cacheKey,Boolean.FALSE);返回豆；}1.3找到所有合适的通知protectedListfindEligibleAdvisors(ClassbeanClass,StringbeanName){//1找到所有候选建议ListcandidateAdvisors=findCandidateAdvisors();//2匹配看是否合适ListeligibleAdvisors=findAdvisorsThatCanApply(candidateAdvisors,beanClass,beanName);扩展顾问（合格顾问）；if(!eligibleAdvisors.isEmpty()){//3在这里排序顾问？eligibleAdvisors=sortAdvisors(eligibleAdvisors);}返回eligibleAdvisors；}1.3.1findCandidateAdvisorsprotectedListfindCandidateAdvisors(){//添加所有根据超类规则找到的Spring顾问。Listadvisors=super.找到CandidateAdvisors();//为bean工厂中的所有AspectJ方面构建顾问程序。if(this.aspectJAdvisorsBuilder!=null){//开始寻找@AspectJ注解类；advisors.addAll(this.aspectJAdvisorsBuilder.buildAspectJAdvisors());返回顾问；}this.aspectJAdvisorsBuilder.buildAspectJAdvisors()主要逻辑：遍历BeanDefinitionMap看是否有@AspectJ注解。如果有，它会遍历方法看是否是通知。如果是通知，会封装成一个InstantiationModelAwarePointcutAdvisorImpl类；然后包裹退货；这个方法也有排序！！在getAdvisorMethod中privateListgetAdvisorMethods(ClassaspectClass){Listmethods=newArrayList<>();ReflectionUtils.doWithMethods(aspectClass,methods::add,adviceMethodFilter);如果(methods.size()>1){methods.sort(adviceMethodComparator);}返回方法；按什么排序？privatestaticfinalComparatoradviceMethodComparator;static{//注意：虽然@After排在@Aft之前erReturning和@AfterThrowing，//@After建议方法实际上将在@AfterReturning和//@AfterThrowing方法之后调用，因为AspectJAfterAdvice.invoke(MethodInvocation)//在`try`块中调用proceed()且仅//在相应的`finally`块中调用@After建议方法。ComparatoradviceKindComparator=newConvertingComparator<>(newInstanceComparator<>(Around.class,Before.class,After.class,AfterReturning.class,AfterThrowing.class),(Converter)方法->{AspectJAnnotationann=AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(方法);返回(ann!=null?ann.getAnnotation():null);});比较器<方法>methodNameComparator=newConvertingComparator<>(Me方法::获取名称);adviceMethodComparator=adviceKindComparator.thenComparing(methodNameComparator);}我们发现是按Around,Before,After,AfterReturning排序的，如果有相同的，则按methodName排序；1.3.2findAdvisorsThatCanApply检查该类是否与PointCut匹配成功，匹配成功则返回列表；protectedListfindAdvisorsThatCanApply(ListcandidateAdvisors,ClassbeanClass,StringbeanName){ProxyCreationContext.setCurrentProxiedBeanName(beanName);}try{//检查这个类是否与PointCut匹配成功，匹配成功，即ok；返回AopUtils.findAdvisorsThatCanApply(candidateAdvisors,beanClass);}最后{ProxyCreationContext.setCurrentProxiedBeanName(null);}}1.3.3findAdvisorsThatCanApply比较两个类的订单大小；Chase，主题逻辑：找到所有Advisor，创建指定的拦截器，例如：在回调方法中加入dynamicAdvisorInterceptor；增强器.create();总结先想一想再做；命名艺术，AutoProxyCreator，AspectJAdvisor，AspectJAdvisorBuilder，XXFactory封装成对象，方便以后扩展
