在refresh方法中,首先调用prepareRefresh方法,
prepareRefresh
getEnvironment().validateRequiredProperties();
校验必须的属性委托了
AbstractPropertyResolver
进行一个校验prepareRefresh方法中都是一些初始化工作,设置开始初始化的的时间startupDate,设置容器状态closed为未关闭状态,容器active设置为激活状态
initPropertySources
子类实现
/** * <p>Replace any stub property sources with actual instances. * @see org.springframework.core.env.PropertySource.StubPropertySource * @see org.springframework.web.context.support.WebApplicationContextUtils#initServletPropertySources */ protected void initPropertySources() { // For subclasses: do nothing by default. }
根据这个特性,我们在日常的开发过程当中,可以用它来判断某个环境变量是否配置,比如,我们可以用它来判定java
的环境变量是否配置了:
可以看到还是刚才的方法,如果我们在方法initPropertySources中,通过方法setRequiredProperties指定必须设置
环境变量名称为“
JAVA_ HOME
”我设置了一定需要属性“
JAVA_HOME
”,那该环境变量的值一定得要存在,否则
getEnvironmentO.validateRequiredPropertie
方法就会去判断名称为“JAVA_ HOME
”的这个环境变量是否存在对的值。
如果不存在相应的环境变量值,就像我们刚才看到的一样就会抛出一个异常,很显然我们通过这个功能特性,就可以在
Sprina容器初始化的时候,及时检测出哪些必要的环境变量有没有配置好.及时发现并排除隐患。初始化BeanFactory
判断是否已经有BeanFacory实例,没有则创建一个DefaultListableBeanFactory,并加载bean定义到此容器中
ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory(); /** * Tell the subclass to refresh the internal bean factory. * @return the fresh BeanFactory instance * @see #refreshBeanFactory() * @see #getBeanFactory() */ protected ConfigurableListableBeanFactory obtainFreshBeanFactory() { refreshBeanFactory(); return getBeanFactory(); }
@Override protected final void refreshBeanFactory() throws BeansException { //判断是否有beanFactory if (hasBeanFactory()) { //销毁容器里的bean信息 destroyBeans(); //关闭beanFactory closeBeanFactory(); } try { //创建 DefaultListableBeanFactory DefaultListableBeanFactory beanFactory = createBeanFactory(); beanFactory.setSerializationId(getId()); //定制化spring容器beanFactory() customizeBeanFactory(beanFactory); //加载bean信息 loadBeanDefinitions(beanFactory); synchronized (this.beanFactoryMonitor) { this.beanFactory = beanFactory; } } catch (IOException ex) { throw new ApplicationContextException("I/O error parsing bean definition source for " + getDisplayName(), ex); } }
prepareBeanFactory
prepareBeanFactorypostProcessBeanFactory
refresh中的postProcessBeanFactory方法,提供给子类的拓展点,可以在ApplicationContext初始化后,对内部的beanFactory进行修改
/** * Modify the application context's internal bean factory after its standard * initialization. All bean definitions will have been loaded, but no beans * will have been instantiated yet. This allows for registering special * BeanPostProcessors etc in certain ApplicationContext implementations. * @param beanFactory the bean factory used by the application context */ protected void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) { }
invokeBeanFactoryPostProcessors
调用bean工厂后置处理器
/** * Instantiate and invoke all registered BeanFactoryPostProcessor beans, * respecting explicit order if given. * <p>Must be called before singleton instantiation. */ protected void invokeBeanFactoryPostProcessors(ConfigurableListableBeanFactory beanFactory) { PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(beanFactory, getBeanFactoryPostProcessors()); // Detect a LoadTimeWeaver and prepare for weaving, if found in the meantime // (e.g. through an @Bean method registered by ConfigurationClassPostProcessor) if (beanFactory.getTempClassLoader() == null && beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) { beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory)); beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader())); } }
BeanFactoryPostProcessor接口提供了一个postProcessBeanFactory方法对内部的beanFactory进行修改
@FunctionalInterface public interface BeanFactoryPostProcessor { /** * Modify the application context's internal bean factory after its standard * initialization. All bean definitions will have been loaded, but no beans * will have been instantiated yet. This allows for overriding or adding * properties even to eager-initializing beans. * @param beanFactory the bean factory used by the application context * @throws org.springframework.beans.BeansException in case of errors */ void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException; }
自定义bean工厂后置处理器
和AbstractApplicationContext中的空方法postProcessBeanFactory()作用类型,但是实现的粒度不同,继承AbstractApplicationContext是基于 ApplicationContext的维度, 如果有多个处理逻辑,其实都耦合在一个ApplicationContext, 而bean工厂后置处理器更为轻量,不同的修改beanFactory的可以拆分成多个BeanFactoryPostProcessor实现
PostProcessorRegistrationDelegate.
invokeBeanFactoryPostProcessors
(beanFactory, getBeanFactoryPostProcessors());
public static void invokeBeanFactoryPostProcessors( ConfigurableListableBeanFactory beanFactory, List<BeanFactoryPostProcessor> beanFactoryPostProcessors) { // Invoke BeanDefinitionRegistryPostProcessors first, if any. Set<String> processedBeans = new HashSet<>(); if (beanFactory instanceof BeanDefinitionRegistry) { //DefaultListableBeanFactory实现了BeanDefinitionRegistry BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory; //常规后处理器 List<BeanFactoryPostProcessor> regularPostProcessors = new ArrayList<>(); //BeanDefinitionRegistryPostProcessor 注册后置处理器 //BeanDefinitionRegistryPostProcessor 继承 BeanFactoryPostProcessor List<BeanDefinitionRegistryPostProcessor> registryProcessors = new ArrayList<>(); for (BeanFactoryPostProcessor postProcessor : beanFactoryPostProcessors) { if (postProcessor instanceof BeanDefinitionRegistryPostProcessor) { BeanDefinitionRegistryPostProcessor registryProcessor = (BeanDefinitionRegistryPostProcessor) postProcessor; registryProcessor.postProcessBeanDefinitionRegistry(registry); registryProcessors.add(registryProcessor); } else { regularPostProcessors.add(postProcessor); } } // Do not initialize FactoryBeans here: We need to leave all regular beans // uninitialized to let the bean factory post-processors apply to them! // Separate between BeanDefinitionRegistryPostProcessors that implement // PriorityOrdered, Ordered, and the rest. List<BeanDefinitionRegistryPostProcessor> currentRegistryProcessors = new ArrayList<>(); // First, invoke the BeanDefinitionRegistryPostProcessors that implement PriorityOrdered. String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanDefinitionRegistryPostProcessor.class, true, false); for (String ppName : postProcessorNames) { if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) { currentRegistryProcessors.add(beanFactory.getBean(ppName, BeanDefinitionRegistryPostProcessor.class)); processedBeans.add(ppName); } } //对 PriorityOrdered或Ordered接口进行排序 sortPostProcessors(currentRegistryProcessors, beanFactory); registryProcessors.addAll(currentRegistryProcessors); invokeBeanDefinitionRegistryPostProcessors(currentRegistryProcessors, registry); //清空已经处理的BeanDefinitionRegistryPostProcessor currentRegistryProcessors.clear(); // Next, invoke the BeanDefinitionRegistryPostProcessors that implement Ordered. postProcessorNames = beanFactory.getBeanNamesForType(BeanDefinitionRegistryPostProcessor.class, true, false); for (String ppName : postProcessorNames) { if (!processedBeans.contains(ppName) && beanFactory.isTypeMatch(ppName, Ordered.class)) { currentRegistryProcessors.add(beanFactory.getBean(ppName, BeanDefinitionRegistryPostProcessor.class)); processedBeans.add(ppName); } } sortPostProcessors(currentRegistryProcessors, beanFactory); registryProcessors.addAll(currentRegistryProcessors); invokeBeanDefinitionRegistryPostProcessors(currentRegistryProcessors, registry); currentRegistryProcessors.clear(); // Finally, invoke all other BeanDefinitionRegistryPostProcessors until no further ones appear. //接口PriorityOrdered和Ordered都没有实现的BeanDefinitionRegistryPostProcessor boolean reiterate = true; while (reiterate) { reiterate = false; postProcessorNames = beanFactory.getBeanNamesForType(BeanDefinitionRegistryPostProcessor.class, true, false); for (String ppName : postProcessorNames) { if (!processedBeans.contains(ppName)) { //去除已经处理过的BeanDefinitionRegistryPostProcessor,防止重复处理 currentRegistryProcessors.add(beanFactory.getBean(ppName, BeanDefinitionRegistryPostProcessor.class)); processedBeans.add(ppName); reiterate = true; } } sortPostProcessors(currentRegistryProcessors, beanFactory); registryProcessors.addAll(currentRegistryProcessors); invokeBeanDefinitionRegistryPostProcessors(currentRegistryProcessors, registry); currentRegistryProcessors.clear(); } // Now, invoke the postProcessBeanFactory callback of all processors handled so far. invokeBeanFactoryPostProcessors(registryProcessors, beanFactory); invokeBeanFactoryPostProcessors(regularPostProcessors, beanFactory); } else { // Invoke factory processors registered with the context instance. invokeBeanFactoryPostProcessors(beanFactoryPostProcessors, beanFactory); } // Do not initialize FactoryBeans here: We need to leave all regular beans // uninitialized to let the bean factory post-processors apply to them! String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanFactoryPostProcessor.class, true, false); // Separate between BeanFactoryPostProcessors that implement PriorityOrdered, // Ordered, and the rest. List<BeanFactoryPostProcessor> priorityOrderedPostProcessors = new ArrayList<>(); List<String> orderedPostProcessorNames = new ArrayList<>(); List<String> nonOrderedPostProcessorNames = new ArrayList<>(); for (String ppName : postProcessorNames) { if (processedBeans.contains(ppName)) { // skip - already processed in first phase above } else if (beanFactory.isTypeMatch(ppName, PriorityOrdered.class)) { priorityOrderedPostProcessors.add(beanFactory.getBean(ppName, BeanFactoryPostProcessor.class)); } else if (beanFactory.isTypeMatch(ppName, Ordered.class)) { orderedPostProcessorNames.add(ppName); } else { nonOrderedPostProcessorNames.add(ppName); } } // First, invoke the BeanFactoryPostProcessors that implement PriorityOrdered. sortPostProcessors(priorityOrderedPostProcessors, beanFactory); invokeBeanFactoryPostProcessors(priorityOrderedPostProcessors, beanFactory); // Next, invoke the BeanFactoryPostProcessors that implement Ordered. List<BeanFactoryPostProcessor> orderedPostProcessors = new ArrayList<>(orderedPostProcessorNames.size()); for (String postProcessorName : orderedPostProcessorNames) { orderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class)); } sortPostProcessors(orderedPostProcessors, beanFactory); invokeBeanFactoryPostProcessors(orderedPostProcessors, beanFactory); // Finally, invoke all other BeanFactoryPostProcessors. List<BeanFactoryPostProcessor> nonOrderedPostProcessors = new ArrayList<>(nonOrderedPostProcessorNames.size()); for (String postProcessorName : nonOrderedPostProcessorNames) { nonOrderedPostProcessors.add(beanFactory.getBean(postProcessorName, BeanFactoryPostProcessor.class)); } invokeBeanFactoryPostProcessors(nonOrderedPostProcessors, beanFactory); // Clear cached merged bean definitions since the post-processors might have // modified the original metadata, e.g. replacing placeholders in values... beanFactory.clearMetadataCache(); }
具体的逻辑如下:
- 首先判断
BeanFactory
是否为BeanDefinitionRegistry
类型,如果是,就按照一定的顺序调用各种后置处理器。如果不是,就直接调用工厂处理器。
- 如果是
BeanDefinitionRegistry
类型,就按照后置处理器的优先级进行调用。调用顺序分为三步: - 首先,调用实现了
PriorityOrdered
接口的BeanDefinitionRegistryPostProcessor
,并按照优先级进行排序。 - 其次,调用实现了
Ordered
接口的BeanDefinitionRegistryPostProcessor
,并按照order
值进行排序。 - 最后,调用没有实现任何接口的
BeanDefinitionRegistryPostProcessor
。
- 完成上述步骤后,调用普通工厂处理器。调用顺序也分为三步:
- 首先,调用实现了
PriorityOrdered
接口的BeanFactoryPostProcessor
,并按照优先级进行排序。 - 其次,调用实现了
Ordered
接口的BeanFactoryPostProcessor
,并按照order
值进行排序。 - 最后,调用没有实现任何接口的
BeanFactoryPostProcessor
。
- 最后清空缓存的元数据缓存。
这些步骤都是在
AbstractApplicationContext
中实现的,而且都是在refresh()
方法中调用的。refresh()
方法中还调用了其他的方法,如prepareRefresh()
、prepareBeanFactory()
、initPropertySources()
等,这些方法都是为了完成Spring容器的初始化工作的。registerBeanPostProcessors
registerBeanPostProcessors初始化消息源
拓展对国际化的支持
初始化事件广播器
/** * Name of the ApplicationEventMulticaster bean in the factory. * If none is supplied, a default SimpleApplicationEventMulticaster is used. * @see org.springframework.context.event.ApplicationEventMulticaster * @see org.springframework.context.event.SimpleApplicationEventMulticaster */ public static final String APPLICATION_EVENT_MULTICASTER_BEAN_NAME = "applicationEventMulticaster"; protected void initApplicationEventMulticaster() { ConfigurableListableBeanFactory beanFactory = getBeanFactory(); if (beanFactory.containsLocalBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME)) { this.applicationEventMulticaster = beanFactory.getBean(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, ApplicationEventMulticaster.class); if (logger.isTraceEnabled()) { logger.trace("Using ApplicationEventMulticaster [" + this.applicationEventMulticaster + "]"); } } else { this.applicationEventMulticaster = new SimpleApplicationEventMulticaster(beanFactory); beanFactory.registerSingleton(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, this.applicationEventMulticaster); if (logger.isTraceEnabled()) { logger.trace("No '" + APPLICATION_EVENT_MULTICASTER_BEAN_NAME + "' bean, using " + "[" + this.applicationEventMulticaster.getClass().getSimpleName() + "]"); } } }
如果没有默认的new 一个
SimpleApplicationEventMulticaster(beanFactory);
注册到Bean工厂这个广播器最终会调用所以的ApplicationListener实现🥱的onApplicationEvent接口
设置监听失败处理器
/** * Set the {@link ErrorHandler} to invoke in case an exception is thrown * from a listener. * <p>Default is none, with a listener exception stopping the current * multicast and getting propagated to the publisher of the current event. * If a {@linkplain #setTaskExecutor task executor} is specified, each * individual listener exception will get propagated to the executor but * won't necessarily stop execution of other listeners. * <p>Consider setting an {@link ErrorHandler} implementation that catches * and logs exceptions (a la * {@link org.springframework.scheduling.support.TaskUtils#LOG_AND_SUPPRESS_ERROR_HANDLER}) * or an implementation that logs exceptions while nevertheless propagating them * (e.g. {@link org.springframework.scheduling.support.TaskUtils#LOG_AND_PROPAGATE_ERROR_HANDLER}). * @since 4.1 */ public void setErrorHandler(@Nullable ErrorHandler errorHandler) { this.errorHandler = errorHandler; }
设置线程池,调用具体的监听器
/** * Set a custom executor (typically a {@link org.springframework.core.task.TaskExecutor}) * to invoke each listener with. * <p>Default is equivalent to {@link org.springframework.core.task.SyncTaskExecutor}, * executing all listeners synchronously in the calling thread. * <p>Consider specifying an asynchronous task executor here to not block the * caller until all listeners have been executed. However, note that asynchronous * execution will not participate in the caller's thread context (class loader, * transaction association) unless the TaskExecutor explicitly supports this. * @see org.springframework.core.task.SyncTaskExecutor * @see org.springframework.core.task.SimpleAsyncTaskExecutor */ public void setTaskExecutor(@Nullable Executor taskExecutor) { this.taskExecutor = taskExecutor; }
没有设置线程池同步调用,设置了线程池用设置的线程池调用
invokeListener
public void multicastEvent(final ApplicationEvent event, @Nullable ResolvableType eventType) { ResolvableType type = (eventType != null ? eventType : resolveDefaultEventType(event)); Executor executor = getTaskExecutor(); for (ApplicationListener<?> listener : getApplicationListeners(event, type)) { if (executor != null) { executor.execute(() -> invokeListener(listener, event)); } else { invokeListener(listener, event); } } } protected void invokeListener(ApplicationListener<?> listener, ApplicationEvent event) { ErrorHandler errorHandler = getErrorHandler(); if (errorHandler != null) { try { doInvokeListener(listener, event); } catch (Throwable err) { errorHandler.handleError(err); } } else { doInvokeListener(listener, event); } } @SuppressWarnings({"rawtypes", "unchecked"}) private void doInvokeListener(ApplicationListener listener, ApplicationEvent event) { try { listener.onApplicationEvent(event); } catch (ClassCastException ex) { String msg = ex.getMessage(); if (msg == null || matchesClassCastMessage(msg, event.getClass())) { // Possibly a lambda-defined listener which we could not resolve the generic event type for // -> let's suppress the exception and just log a debug message. Log logger = LogFactory.getLog(getClass()); if (logger.isTraceEnabled()) { logger.trace("Non-matching event type for listener: " + listener, ex); } } else { throw ex; } } }
这其实是用了观察者模式
ApplicationListener
spring提供的拓展接口,可以通过这个
@FunctionalInterface public interface ApplicationListener<E extends ApplicationEvent> extends EventListener { /** * Handle an application event. * @param event the event to respond to */ void onApplicationEvent(E event); }
registerListeners();
protected void registerListeners() { // Register statically specified listeners first. for (ApplicationListener<?> listener : getApplicationListeners()) { getApplicationEventMulticaster().addApplicationListener(listener); } // Do not initialize FactoryBeans here: We need to leave all regular beans // uninitialized to let post-processors apply to them! String[] listenerBeanNames = getBeanNamesForType(ApplicationListener.class, true, false); for (String listenerBeanName : listenerBeanNames) { getApplicationEventMulticaster().addApplicationListenerBean(listenerBeanName); } // Publish early application events now that we finally have a multicaster... Set<ApplicationEvent> earlyEventsToProcess = this.earlyApplicationEvents; this.earlyApplicationEvents = null; if (earlyEventsToProcess != null) { for (ApplicationEvent earlyEvent : earlyEventsToProcess) { getApplicationEventMulticaster().multicastEvent(earlyEvent); } } }
初始化非延迟加载的单例Bean
protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) { // Initialize conversion service for this context. if (beanFactory.containsBean(CONVERSION_SERVICE_BEAN_NAME) && beanFactory.isTypeMatch(CONVERSION_SERVICE_BEAN_NAME, ConversionService.class)) { beanFactory.setConversionService( beanFactory.getBean(CONVERSION_SERVICE_BEAN_NAME, ConversionService.class)); } // Register a default embedded value resolver if no bean post-processor // (such as a PropertyPlaceholderConfigurer bean) registered any before: // at this point, primarily for resolution in annotation attribute values. if (!beanFactory.hasEmbeddedValueResolver()) { beanFactory.addEmbeddedValueResolver(strVal -> getEnvironment().resolvePlaceholders(strVal)); } // Initialize LoadTimeWeaverAware beans early to allow // registering their transformers early. String[] weaverAwareNames = beanFactory.getBeanNamesForType(LoadTimeWeaverAware.class, false, false); for (String weaverAwareName : weaverAwareNames) { getBean(weaverAwareName); } // Stop using the temporary ClassLoader for type matching. beanFactory.setTempClassLoader(null); // Allow for caching all bean definition metadata, not expecting further changes. beanFactory.freezeConfiguration(); // Instantiate all remaining (non-lazy-init) singletons. beanFactory.preInstantiateSingletons(); }
graph TD; A[start] -->B[initialize conversion service]; A --> C[register embedded value resolver]; A --> D[initialize LoadTimeWeaverAware beans]; A --> E[stop using temporary ClassLoader]; A --> F[freeze bean definition metadata]; A --> G[instantiate remaining singletons]; B --> H{conversion service exists}; C --> I{embedded value resolver exists}; D --> J[get bean names for LoadTimeWeaverAware]; J --> K{any LoadTimeWeaverAware beans}; K -->|yes| L[get bean]; L --> J; H -->|yes| M[set conversion service]; I -->|no| N[add embedded value resolver]; N --> O[resolve placeholders]; F --> P[allow caching bean definition metadata]; G --> Q[pre-instantiate singletons];
preInstantiateSingletons
public void preInstantiateSingletons() throws BeansException { if (logger.isTraceEnabled()) { logger.trace("Pre-instantiating singletons in " + this); } // Iterate over a copy to allow for init methods which in turn register new bean definitions. // While this may not be part of the regular factory bootstrap, it does otherwise work fine. List<String> beanNames = new ArrayList<>(this.beanDefinitionNames); // Trigger initialization of all non-lazy singleton beans... for (String beanName : beanNames) { RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName); //如果非抽象、单例、非懒加载的bean if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) { if (isFactoryBean(beanName)) { Object bean = getBean(FACTORY_BEAN_PREFIX + beanName); if (bean instanceof FactoryBean) { final FactoryBean<?> factory = (FactoryBean<?>) bean; boolean isEagerInit; if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) { isEagerInit = AccessController.doPrivileged((PrivilegedAction<Boolean>) ((SmartFactoryBean<?>) factory)::isEagerInit, getAccessControlContext()); } else { isEagerInit = (factory instanceof SmartFactoryBean && ((SmartFactoryBean<?>) factory).isEagerInit()); } if (isEagerInit) { getBean(beanName); } } } else { getBean(beanName); } } } // Trigger post-initialization callback for all applicable beans... for (String beanName : beanNames) { Object singletonInstance = getSingleton(beanName); if (singletonInstance instanceof SmartInitializingSingleton) { final SmartInitializingSingleton smartSingleton = (SmartInitializingSingleton) singletonInstance; if (System.getSecurityManager() != null) { AccessController.doPrivileged((PrivilegedAction<Object>) () -> { smartSingleton.afterSingletonsInstantiated(); return null; }, getAccessControlContext()); } else { smartSingleton.afterSingletonsInstantiated(); } } } }
finishRefresh
初始化生命周期处理器,并发出相应的事件进行通知
/** * Finish the refresh of this context, invoking the LifecycleProcessor's * onRefresh() method and publishing the * {@link org.springframework.context.event.ContextRefreshedEvent}. */ protected void finishRefresh() { // Clear context-level resource caches (such as ASM metadata from scanning). clearResourceCaches(); // Initialize lifecycle processor for this context. initLifecycleProcessor(); // Propagate refresh to lifecycle processor first. getLifecycleProcessor().onRefresh(); // Publish the final event. publishEvent(new ContextRefreshedEvent(this)); // Participate in LiveBeansView MBean, if active. LiveBeansView.registerApplicationContext(this); }
LifecycleProcessor
可以看到,在方法initLifecycleProcessor中,首先就是到Spring容器中看下是否存在名称为lifecycleProcessor的bean。
如果存在的话,直接从Spring容器中获取出来,并赋值给成员变量lifecycleProcessor,如果不存在的话默认会创建一个DefaultLifecycleProcessor类型的对象,并赋值给成员变量lifecycleProcessor,最后再注入到Spring容器中
/** * Strategy interface for processing Lifecycle beans within the ApplicationContext. * * @author Mark Fisher * @author Juergen Hoeller * @since 3.0 */ public interface LifecycleProcessor extends Lifecycle { /** * Notification of context refresh, e.g. for auto-starting components. */ void onRefresh(); /** * Notification of context close phase, e.g. for auto-stopping components. */ void onClose(); }
DefaultLifecycleProcessor 最终回去执行所有直接或者间接实现Lifecycle的bean的生命周期方法
private void startBeans(boolean autoStartupOnly) { Map<String, Lifecycle> lifecycleBeans = getLifecycleBeans(); Map<Integer, LifecycleGroup> phases = new HashMap<>(); lifecycleBeans.forEach((beanName, bean) -> { if (!autoStartupOnly || (bean instanceof SmartLifecycle && ((SmartLifecycle) bean).isAutoStartup())) { int phase = getPhase(bean); LifecycleGroup group = phases.get(phase); if (group == null) { group = new LifecycleGroup(phase, this.timeoutPerShutdownPhase, lifecycleBeans, autoStartupOnly); phases.put(phase, group); } group.add(beanName, bean); } }); if (!phases.isEmpty()) { List<Integer> keys = new ArrayList<>(phases.keySet()); Collections.sort(keys); for (Integer key : keys) { phases.get(key).start(); } } } public void start() { if (this.members.isEmpty()) { return; } if (logger.isDebugEnabled()) { logger.debug("Starting beans in phase " + this.phase); } Collections.sort(this.members); for (LifecycleGroupMember member : this.members) { doStart(this.lifecycleBeans, member.name, this.autoStartupOnly); } }
doStart方法最终调用每个lfiecycle的start()方法
publishEvent
protected void publishEvent(Object event, @Nullable ResolvableType eventType) { Assert.notNull(event, "Event must not be null"); // Decorate event as an ApplicationEvent if necessary ApplicationEvent applicationEvent; if (event instanceof ApplicationEvent) { applicationEvent = (ApplicationEvent) event; } else { applicationEvent = new PayloadApplicationEvent<>(this, event); if (eventType == null) { eventType = ((PayloadApplicationEvent<?>) applicationEvent).getResolvableType(); } } // Multicast right now if possible - or lazily once the multicaster is initialized if (this.earlyApplicationEvents != null) { this.earlyApplicationEvents.add(applicationEvent); } else { //获取之前初始化的事件广播器,调用广播器的广播方法 getApplicationEventMulticaster().multicastEvent(applicationEvent, eventType); } // Publish event via parent context as well... if (this.parent != null) { if (this.parent instanceof AbstractApplicationContext) { ((AbstractApplicationContext) this.parent).publishEvent(event, eventType); } else { this.parent.publishEvent(event); } } }