位置在abstractApplicationContext.refresh()SpringBoot启动流程往期博客SpringBoot启动流程ConfigurationClassPostProcessorbean的加载流程publicvoidrefresh(){......invokeBeanFactoryPostProcessors(beanFactory);registerBeanPostProcessors(beanFactory);......finishBeanFactoryInitialization(beanFactory);......finishRefresh();}一、invokeBeanFactoryPostProcessors()先执行 beanDefinitionRegistryPostProcessor 的 postProcessBeanDefinitionRegistry()再执行 beanFactoryPostProcessor 的 postProcessBeanFactory()数据来源有 applicationContext.beanFactoryPostProcessors以及类型为BeanDefinitionRegistryPostProcessor、BeanFactoryPostProcessor的beanDefinition其中有非常重要的beanDefinitionRegistryPostProcessorConfigurationClassPostProcessor在postProcessBeanDefinitionRegistry()中加载自定义bean的beanDefinition参考博客ConfigurationClassPostProcessor二、registerBeanPostProcessors()提前创建beanDefinitionMap中类型为BeanPostProcessor的bean放到beanFactory的beanPostProcessors集合中。三、initApplicationEventMulticaster()再创建应用上下文时会创建AnnotatedBeanDefinitionReader对象在AnnotatedBeanDefinitionReader的构造函数中会向beanFactory注册两个beanDefinitionEventListenerMethodProcessor、DefaultEventListenerFactory。其中EventListenerMethodProcessor是SmartInitializingSingleton实现类在preInstantiateSingletons()方法的最后一步调用类型为SmartInitializingSingleton的bean的afterSingletonsInstantiated()方法。在EventListenerMethodProcessor的afterSingletonsInstantiated()方法中会遍历bean找出方法上含有EventListener的bean通过DefaultEventListenerFactory将含有EventListener的方法封装成一个ApplicationListenerApplicationListenerMethodAdapter然后将这个应用监听器保存到应用上下文的applicationListeners集合中以及引用上下文的SimpleApplicationEventMulticaster的DefaultListenerRetriever的applicationListeners集合中。通过applicationContext.publishEvent(new MyApplicationEvent(App.class, Arrays.asList(“a”,“b”,“c”)));发布事件时会调用应用上下文的SimpleApplicationEventMulticaster的multicastEvent()方法在multicastEvent()方法中会遍历DefaultListenerRetriever的applicationListeners集合根据publishEvent()方法的参数类型匹配EventListener注解的class类型匹配到对应的ApplicationListenerMethodAdapter后会调用该ApplicationListenerMethodAdapter的onApplicationEvent()方法在该方法中通过反射调用EventListener的方法。四、finishBeanFactoryInitialization()finishBeanFactoryInitialization()中会调用beanFactory 的 preInstantiateSingletons()publicvoidpreInstantiateSingletons()throwsBeansException{......ListStringbeanNamesnewArrayList(this.beanDefinitionNames);for(StringbeanName:beanNames){......getBean(beanName);......}for(StringbeanName:beanNames){ObjectsingletonInstancegetSingleton(beanName);if(singletonInstanceinstanceofSmartInitializingSingleton){......SmartInitializingSingletonsmartSingleton(SmartInitializingSingleton)singletonInstance;......smartSingleton.afterSingletonsInstantiated();......}}}getBean()为bean的加载流程参考博客bean的加载流程bean加载完后遍历bean集合如果实现SmartInitializingSingleton调用afterSingletonsInstantiated()方法。五、finishRefresh()遍历bean集合如果实现SmartLifecycle并且isAutoStartup()方法返回值为trueisRunning()方法返回值为false时调用其start()方法。
位置在abstractApplicationContext.refresh()SpringBoot启动流程往期博客SpringBoot启动流程ConfigurationClassPostProcessorbean的加载流程publicvoidrefresh(){......invokeBeanFactoryPostProcessors(beanFactory);registerBeanPostProcessors(beanFactory);......finishBeanFactoryInitialization(beanFactory);......finishRefresh();}一、invokeBeanFactoryPostProcessors()先执行 beanDefinitionRegistryPostProcessor 的 postProcessBeanDefinitionRegistry()再执行 beanFactoryPostProcessor 的 postProcessBeanFactory()数据来源有 applicationContext.beanFactoryPostProcessors以及类型为BeanDefinitionRegistryPostProcessor、BeanFactoryPostProcessor的beanDefinition其中有非常重要的beanDefinitionRegistryPostProcessorConfigurationClassPostProcessor在postProcessBeanDefinitionRegistry()中加载自定义bean的beanDefinition参考博客ConfigurationClassPostProcessor二、registerBeanPostProcessors()提前创建beanDefinitionMap中类型为BeanPostProcessor的bean放到beanFactory的beanPostProcessors集合中。三、initApplicationEventMulticaster()再创建应用上下文时会创建AnnotatedBeanDefinitionReader对象在AnnotatedBeanDefinitionReader的构造函数中会向beanFactory注册两个beanDefinitionEventListenerMethodProcessor、DefaultEventListenerFactory。其中EventListenerMethodProcessor是SmartInitializingSingleton实现类在preInstantiateSingletons()方法的最后一步调用类型为SmartInitializingSingleton的bean的afterSingletonsInstantiated()方法。在EventListenerMethodProcessor的afterSingletonsInstantiated()方法中会遍历bean找出方法上含有EventListener的bean通过DefaultEventListenerFactory将含有EventListener的方法封装成一个ApplicationListenerApplicationListenerMethodAdapter然后将这个应用监听器保存到应用上下文的applicationListeners集合中以及引用上下文的SimpleApplicationEventMulticaster的DefaultListenerRetriever的applicationListeners集合中。通过applicationContext.publishEvent(new MyApplicationEvent(App.class, Arrays.asList(“a”,“b”,“c”)));发布事件时会调用应用上下文的SimpleApplicationEventMulticaster的multicastEvent()方法在multicastEvent()方法中会遍历DefaultListenerRetriever的applicationListeners集合根据publishEvent()方法的参数类型匹配EventListener注解的class类型匹配到对应的ApplicationListenerMethodAdapter后会调用该ApplicationListenerMethodAdapter的onApplicationEvent()方法在该方法中通过反射调用EventListener的方法。四、finishBeanFactoryInitialization()finishBeanFactoryInitialization()中会调用beanFactory 的 preInstantiateSingletons()publicvoidpreInstantiateSingletons()throwsBeansException{......ListStringbeanNamesnewArrayList(this.beanDefinitionNames);for(StringbeanName:beanNames){......getBean(beanName);......}for(StringbeanName:beanNames){ObjectsingletonInstancegetSingleton(beanName);if(singletonInstanceinstanceofSmartInitializingSingleton){......SmartInitializingSingletonsmartSingleton(SmartInitializingSingleton)singletonInstance;......smartSingleton.afterSingletonsInstantiated();......}}}getBean()为bean的加载流程参考博客bean的加载流程bean加载完后遍历bean集合如果实现SmartInitializingSingleton调用afterSingletonsInstantiated()方法。五、finishRefresh()遍历bean集合如果实现SmartLifecycle并且isAutoStartup()方法返回值为trueisRunning()方法返回值为false时调用其start()方法。
