publicabstractclassAbstractApplicationContextextendsDefaultResourceLoader implementsConfigurableApplicationContext{ @Override publicvoidrefresh()throws BeansException, IllegalStateException { synchronized (this.startupShutdownMonitor) { // Prepare this context for refreshing. prepareRefresh(); // Tell the subclass to refresh the internal bean factory. ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory(); // Prepare the bean factory for use in this context. prepareBeanFactory(beanFactory); try { // Allows post-processing of the bean factory in context subclasses. postProcessBeanFactory(beanFactory); // Invoke factory processors registered as beans in the context. invokeBeanFactoryPostProcessors(beanFactory); // Register bean processors that intercept bean creation. registerBeanPostProcessors(beanFactory); // Initialize message source for this context. initMessageSource(); // Initialize event multicaster for this context. initApplicationEventMulticaster(); // Initialize other special beans in specific context subclasses. onRefresh(); // Check for listener beans and register them. registerListeners(); // Instantiate all remaining (non-lazy-init) singletons. finishBeanFactoryInitialization(beanFactory); // Last step: publish corresponding event. finishRefresh(); }
} } }
prepareRefresh
激活开启容器，表示在真正做refresh操作之前需要准备做的事情：
设置Spring容器的启动时间，撤销关闭状态，开启活跃状态。
初始化属性源信息(Property)
验证环境信息里一些必须存在的属性
初始化一些事件集合
protectedvoidprepareRefresh(){ // Switch to active. // 当前激活时间 this.startupDate = System.currentTimeMillis(); // 设定当前容器未关闭 this.closed.set(false); // 设置当前容器处于激活状态 this.active.set(true); // 初始化一下属性(该方法默认是空的,是提供给子类来实现的,有些bean初始化需要一些依赖加载配置 // Initialize any placeholder property sources in the context environment. initPropertySources(); // 校验熟悉是否合法 // Validate that all properties marked as required are resolvable: // see ConfigurablePropertyResolver#setRequiredProperties getEnvironment().validateRequiredProperties();
// Allow for the collection of early ApplicationEvents, // to be published once the multicaster is available... this.earlyApplicationEvents = new LinkedHashSet<>(); }
protectedvoidprepareBeanFactory(ConfigurableListableBeanFactory beanFactory){ // Tell the internal bean factory to use the context's class loader etc. beanFactory.setBeanClassLoader(getClassLoader());
// Register early post-processor for detecting inner beans as ApplicationListeners. beanFactory.addBeanPostProcessor(new ApplicationListenerDetector(this));
// 添加编译时支持AspectJ if (beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) { beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory)); // Set a temporary ClassLoader for type matching. beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader())); }
// 注入系统相关Bean if (!beanFactory.containsLocalBean(ENVIRONMENT_BEAN_NAME)) { beanFactory.registerSingleton(ENVIRONMENT_BEAN_NAME, getEnvironment()); } if (!beanFactory.containsLocalBean(SYSTEM_PROPERTIES_BEAN_NAME)) { beanFactory.registerSingleton(SYSTEM_PROPERTIES_BEAN_NAME, getEnvironment().getSystemProperties()); } if (!beanFactory.containsLocalBean(SYSTEM_ENVIRONMENT_BEAN_NAME)) { beanFactory.registerSingleton(SYSTEM_ENVIRONMENT_BEAN_NAME, getEnvironment().getSystemEnvironment()); } }
protectedvoidfinishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory){ // Initialize conversion service for this context. // 为容器初始化ConversionService，这个主要是做类型转化 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. // 若没有设置值解析器，那就注册一个默认的值解析器 if (!beanFactory.hasEmbeddedValueResolver()) { beanFactory.addEmbeddedValueResolver(strVal -> getEnvironment().resolvePlaceholders(strVal)); }
// Initialize LoadTimeWeaverAware beans early to allow for 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. // 清空临时类加载器 beanFactory.setTempClassLoader(null);
// Allow for caching all bean definition metadata, not expecting further changes. // 缓存（快照）下当前所有的Bean定义信息 beanFactory beanFactory.freezeConfiguration();
// Instantiate all remaining (non-lazy-init) singletons. // 实例化所有单例对象 beanFactory.preInstantiateSingletons(); }
finishRefresh
完成bean的创建初始化工作,完成 IoC 容器的创建
protectedvoidfinishRefresh(){ // Clear context-level resource caches (such as ASM metadata from scanning). // 表示清除一些resourceCaches，清除context级别的资源缓存，比如ASM的元数据 clearResourceCaches();
// Initialize lifecycle processor for this context. // 初始化所有的LifecycleProcessor，与生命周期相关 initLifecycleProcessor();
// Propagate refresh to lifecycle processor first. getLifecycleProcessor().onRefresh();
// Publish the final event. // 发布容器刷新的事件： publishEvent(new ContextRefreshedEvent(this));
// Participate in LiveBeansView MBean, if active. LiveBeansView.registerApplicationContext(this); }
