Spring源码解析-applicationContext.doc

Spring源码解析-applicationContextDemouml类图ApplicationContextApplicationListener源码解析主流程obtainFreshBeanFactoryprepareBeanFactoryinvokeBeanFactoryPostProcessorsregisterBeanPostProcessorsregisterListenersfinishRefresh总结在已经有BeanFactory可以完成Ioc功能情况下，spring又提供了ApplicationContext，why？可以简单理解BeanFactory为可用，ApplicationContext封装了Beanfactory，提供了上下文、国际化、监听等更多的可选功能，让其能用，使用时，优先使用ApplicationContext。Demo跟beanfactory的demo唯一不同的就是：/BeanFactory ctx = new XmlBeanFactory(new ClassPathResource(spring.xml);ApplicationContext ctx = new ClassPathXmlApplicationContext(spring.xml);uml类图ApplicationContextapplicationContextApplicationListenerApplicationListener源码解析主流程/ClassPathXmlApplicationContextpublic ClassPathXmlApplicationContext(String configLocations, boolean refresh) throws BeansException this(configLocations, refresh, null);public ClassPathXmlApplicationContext(String configLocations, boolean refresh, ApplicationContext parent) throws BeansException super(parent); / 设置configLocations setConfigLocations(configLocations); if (refresh) refresh(); /AbstractApplicationContextpublic void refresh() throws BeansException, IllegalStateException synchronized (this.startupShutdownMonitor) / 设置和校验系统变量和环境变量的值 prepareRefresh(); / 获取beanFactory ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory(); / 配置BeanFactory上下文 prepareBeanFactory(beanFactory); try / 子类扩展，beanFactory的后置处理 postProcessBeanFactory(beanFactory); / 调用BeanFactory的后置处理器 invokeBeanFactoryPostProcessors(beanFactory); / 注册bean processors，只是注册，bean创建时调用. registerBeanPostProcessors(beanFactory); / 国际化 initMessageSource(); / 初始化监听的Multicaster，有自定义就是用自定义，没有就使用默认SimpleApplicationEventMulticaster initApplicationEventMulticaster(); / 子类扩展 onRefresh(); / 注册listen registerListeners(); / 实例化所有非延迟加载的bean，相当于循环调用getbean finishBeanFactoryInitialization(beanFactory); / 完成刷新，通知LifecycleProcessor，ContextRefreshedEvent事件（这个很有用，可以监听这个事件） finishRefresh(); catch (BeansException ex) / Destroy already created singletons to avoid dangling resources. destroyBeans(); / Reset active flag. cancelRefresh(ex); / Propagate exception to caller. throw ex; 整个refresh过程，流程清晰，从spring学了这一招。obtainFreshBeanFactory这个流程里面有个需要注意的地方：/AbstractRefreshableApplicationContextprotected void customizeBeanFactory(DefaultListableBeanFactory beanFactory) if (this.allowBeanDefinitionOverriding != null) beanFactory.setAllowBeanDefinitionOverriding(this.allowBeanDefinitionOverriding); if (this.allowCircularReferences != null) beanFactory.setAllowCircularReferences(this.allowCircularReferences); / 用于Autowire和Qualifier，没试过，TODO beanFactory.setAutowireCandidateResolver(new QualifierAnnotationAutowireCandidateResolver();prepareBeanFactory/ClassPathXmlApplicationContextprotected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) / Tell the internal bean factory to use the contexts class loader etc. beanFactory.setBeanClassLoader(getClassLoader(); / 之前beanfactory没有设置classLoader beanFactory.setBeanExpressionResolver(new StandardBeanExpressionResolver(); / el表达式 beanFactory.addPropertyEditorRegistrar(new ResourceEditorRegistrar(this, this.getEnvironment(); / 配置属性注入编辑器 /ApplicationContextAwareProcessor这个beanpostprocessor，在实例化前postProcessBeforeInitialization设置下面忽略的依赖 beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this); beanFactory.ignoreDependencyInterface(ResourceLoaderAware.class); beanFactory.ignoreDependencyInterface(ApplicationEventPublisherAware.class); beanFactory.ignoreDependencyInterface(MessageSourceAware.class); beanFactory.ignoreDependencyInterface(ApplicationContextAware.class); beanFactory.ignoreDependencyInterface(EnvironmentAware.class); / 设置几个自动注册的依赖，注入的时候直接用 beanFactory.registerResolvableDependency(BeanFactory.class, beanFactory); beanFactory.registerResolvableDependency(ResourceLoader.class, this); beanFactory.registerResolvableDependency(ApplicationEventPublisher.class, this); beanFactory.registerResolvableDependency(ApplicationContext.class, this); / aop类加载期织入支持Detect a LoadTimeWeaver and prepare for weaving, if found. 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(); / / 注册一些默认bean，方便使用 if (!beanFactory.containsBean(ENVIRONMENT_BEAN_NAME) beanFactory.registerSingleton(ENVIRONMENT_BEAN_NAME, getEnvironment(); if (!beanFactory.containsBean(SYSTEM_PROPERTIES_BEAN_NAME) beanFactory.registerSingleton(SYSTEM_PROPERTIES_BEAN_NAME, getEnvironment().getSystemProperties(); if (!beanFactory.containsBean(SYSTEM_ENVIRONMENT_BEAN_NAME) beanFactory.registerSingleton(SYSTEM_ENVIRONMENT_BEAN_NAME, getEnvironment().getSystemEnvironment(); invokeBeanFactoryPostProcessors/AbstractApplicationContext/BeanFactoryPostProcessor激活调用protected void invokeBeanFactoryPostProcessors(ConfigurableListableBeanFactory beanFactory) / Invoke BeanDefinitionRegistryPostProcessors first, if any. Set processedBeans = new HashSet(); /BeanDefinitionRegistry中的BeanPostProcessor if (beanFactory instanceof BeanDefinitionRegistry) BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory; List regularPostProcessors = new LinkedList(); List registryPostProcessors = new LinkedList(); /硬编码进来的 for (BeanFactoryPostProcessor postProcessor : getBeanFactoryPostProcessors() if (postProcessor instanceof BeanDefinitionRegistryPostProcessor) /BeanDefinitionRegistryPostProcessor继承了BeanFactoryPostProcessor，多了个调用postProcessBeanDefinitionRegistry，这里区分下 BeanDefinitionRegistryPostProcessor registryPostProcessor = (BeanDefinitionRegistryPostProcessor) postProcessor; registryPostProcessor.postProcessBeanDefinitionRegistry(registry); registryPostProcessors.add(registryPostProcessor); else regularPostProcessors.add(postProcessor); /配置的bean中获取 Map beanMap = beanFactory.getBeansOfType(BeanDefinitionRegistryPostProcessor.class, true, false); List registryPostProcessorBeans = new ArrayList(beanMap.values(); OrderComparator.sort(registryPostProcessorBeans); for (BeanDefinitionRegistryPostProcessor postProcessor : registryPostProcessorBeans) /调用postProcessBnDefinitionRegistry postProcessor.postProcessBeanDefinitionRegistry(registry); /调用postProcessBeanFactory invokeBeanFactoryPostProcessors(registryPostProcessors, beanFactory); invokeBeanFactoryPostProcessors(registryPostProcessorBeans, beanFactory); invokeBeanFactoryPostProcessors(regularPostProcessors, beanFactory); / processedBeans包含所有处理过的 processedBeans.addAll(beanMap.keySet(); else / Invoke factory processors registered with the context instance. invokeBeanFactoryPostProcessors(getBeanFactoryPostProcessors(), beanFactory); / beanFactory中获取BeanFactoryPostProcessor String postProcessorNames = beanFactory.getBeanNamesForType(BeanFactoryPostProcessor.class, true, false); / Separate between BeanFactoryPostProcessors that implement PriorityOrdered, / Ordered, and the rest. List priorityOrderedPostProcessors = new ArrayList(); List orderedPostProcessorNames = new ArrayList(); List nonOrderedPostProcessorNames = new ArrayList(); for (String ppName : postProcessorNames) / 按照PriorityOrderedOrdered其他区分下，如果已经处理过，会过滤掉，不会重复处理 if (processedBeans.contains(ppName) / skip - already processed in first phase above else if (isTypeMatch(ppName, PriorityOrdered.class) priorityOrderedPostProcessors.add(beanFactory.getBean(ppName, BeanFactoryPostProcessor.class); else if (isTypeMatch(ppName, Ordered.class) orderedPostProcessorNames.add(ppName); else nonOrderedPostProcessorNames.add(ppName); / 对分类过的排序然后调用 / First, invoke the BeanFactoryPostProcessors that implement PriorityOrdered. OrderComparator.sort(priorityOrderedPostProcessors); invokeBeanFactoryPostProcessors(priorityOrderedPostProcessors, beanFactory); / Next, invoke the BeanFactoryPostProcessors that implement Ordered. List orderedPostProcessors = new ArrayList(); for (String postProcessorName : orderedPostProcessorNames) orderedPostProcessors.add(getBean(postProcessorName, BeanFactoryPostProcessor.class); OrderComparator.sort(orderedPostProcessors); invokeBeanFactoryPostProcessors(orderedPostProcessors, beanFactory); / Finally, invoke all other BeanFactoryPostProcessors. List nonOrderedPostProcessors = new ArrayList(); for (String postProcessorName : nonOrderedPostProcessorNames) nonOrderedPostProcessors.add(getBean(postProcessorName, BeanFactoryPostProcessor.class); invokeBeanFactoryPostProcessors(nonOrderedPostProcessors, beanFactory);registerBeanPostProcessors/AbstractApplicationContext/注册所有的BeanPostProcessor，只注册，不调用protected void registerBeanPostProcessors(ConfigurableListableBeanFactory beanFactory) String postProcessorNames = beanFactory.getBeanNamesForType(BeanPostProcessor.class, true, false); / 注册BeanPostProcessorChecker，只是info日志表明bean没有被所有processor处理，没感觉想干嘛 int beanProcessorTargetCount = beanFactory.getBeanPostProcessorCount() + 1 + postProcessorNames.length; beanFactory.addBeanPostProcessor(new BeanPostProcessorChecker(beanFactory, beanProcessorTargetCount); / 按照实现PriorityOrdered,Ordered,其他.分类排序注册到beanfactory List priorityOrderedPostProcessors = new ArrayList(); List internalPostProcessors = new ArrayList(); List orderedPostProcessorNames = new ArrayList(); List nonOrderedPostProcessorNames = new ArrayList(); for (String ppName : postProcessorNames) if (isTypeMatch(ppName, PriorityOrdered.class) BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); priorityOrderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) internalPostProcessors.add(pp); else if (isTypeMatch(ppName, Ordered.class) orderedPostProcessorNames.add(ppName); else nonOrderedPostProcessorNames.add(ppName); / First, register the BeanPostProcessors that implement PriorityOrdered. OrderComparator.sort(priorityOrderedPostProcessors); registerBeanPostProcessors(beanFactory, priorityOrderedPostProcessors); / Next, register the BeanPostProcessors that implement Ordered. List orderedPostProcessors = new ArrayList(); for (String ppName : orderedPostProcessorNames) BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); orderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) internalPostProcessors.add(pp); OrderComparator.sort(orderedPostProcessors); registerBeanPostProcessors(beanFactory, orderedPostProcessors); / Now, register all regular BeanPostProcessors. List nonOrderedPostProcessors = new ArrayList(); for (String ppName : nonOrderedPostProcessorNames) BeanPostProcessor pp = beanFactory.getBean(ppName, BeanPostProcessor.class); nonOrderedPostProcessors.add(pp); if (pp instanceof MergedBeanDefinitionPostProcessor) internalPostProcessors.add(pp); registerBeanPostProcessors(beanFactory, nonOrderedPostProcessors); / Finally, re-register all internal BeanPostProcessors. OrderComparator.sort(internalPostProcessors); registerBeanPostProcessors(beanFactory, internalPostProcessors); /ApplicationListenerDetector初始化后，如果是liste