Spring源码 16 IOC refresh方法11

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发布时间：2020-08-01

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参考源

《Spring源码深度解析(第2版)》

版本

本文章基于 Spring 5.3.15

Spring IOC 的核心是 AbstractApplicationContext 的 refresh 方法。
其中一共有 13 个主要方法，这里分析第 11 个：finishBeanFactoryInitialization。

1 AbstractApplicationContext

1-1 初始化剩下的单实例

finishBeanFactoryInitialization(beanFactory)

protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) {   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));   }   if (!beanFactory.hasEmbeddedValueResolver()) {      beanFactory.addEmbeddedValueResolver(strVal -> getEnvironment().resolvePlaceholders(strVal));   }   String[] weaverAwareNames = beanFactory.getBeanNamesForType(LoadTimeWeaverAware.class, false, false);   for (String weaverAwareName : weaverAwareNames) {      getBean(weaverAwareName);   }   beanFactory.setTempClassLoader(null);   // 冻结所有的 bean 定义，说明注册的 bean 定义将不被修改或任何进一步的处理   beanFactory.freezeConfiguration();   // 初始化剩下的单实例(非惰性的)   beanFactory.preInstantiateSingletons();}

1-2 冻结所有的 bean 定义

beanFactory.freezeConfiguration()

2 DefaultListableBeanFactory

public void freezeConfiguration() {   this.configurationFrozen = true;   this.frozenBeanDefinitionNames = StringUtils.toStringArray(this.beanDefinitionNames);}

1 AbstractApplicationContext

1-2 初始化剩下的单实例

beanFactory.preInstantiateSingletons()

2 DefaultListableBeanFactory

public void preInstantiateSingletons() throws BeansException {   if (logger.isTraceEnabled()) {      logger.trace("Pre-instantiating singletons in " + this);   }   List
    
      beanNames = new ArrayList<>(this.beanDefinitionNames);   for (String beanName : beanNames) {      RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);      if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {         if (isFactoryBean(beanName)) {            Object bean = getBean(FACTORY_BEAN_PREFIX + beanName);            if (bean instanceof FactoryBean) {               FactoryBean
      factory = (FactoryBean
     ) bean;               boolean isEagerInit;               if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) {                  isEagerInit = AccessController.doPrivileged(                        (PrivilegedAction
     
      ) ((SmartFactoryBean
      ) factory)::isEagerInit,                        getAccessControlContext());               }               else {                  isEagerInit = (factory instanceof SmartFactoryBean &&                        ((SmartFactoryBean
      ) factory).isEagerInit());               }               if (isEagerInit) {                  getBean(beanName);               }            }         }         else {            getBean(beanName);         }      }   }   for (String beanName : beanNames) {      Object singletonInstance = getSingleton(beanName);      if (singletonInstance instanceof SmartInitializingSingleton) {         StartupStep smartInitialize = this.getApplicationStartup().start("spring.beans.smart-initialize").tag("beanName", beanName);         SmartInitializingSingleton smartSingleton = (SmartInitializingSingleton) singletonInstance;         if (System.getSecurityManager() != null) {            AccessController.doPrivileged((PrivilegedAction