Spring源码 08 IOC refresh方法3

参考源

https://www.bilibili.com/video/BV1tR4y1F75R?spm_id_from=333.337.search-card.all.click

https://www.bilibili.com/video/BV12Z4y197MU?spm_id_from=333.999.0.0

《Spring源码深度解析（第2版）》

版本

本文章基于 Spring 5.3.15

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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 3 个：prepareBeanFactory。

1 AbstractApplicationContext

1-1 对 BeanFactory 进行功能填充

prepareBeanFactory(beanFactory)

protected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) {
   // 设置 beanFactory 的 classLoader 为当前 context 的 classLoader
   beanFactory.setBeanClassLoader(getClassLoader());
   if (!shouldIgnoreSpel) {
      /**
       * 设置bean Factory 的表达式语言处理桥， Spring3 增加了表达式语言的支持
       * 默认可以使用 #{bean.xxx} 的形式来调用相关属性值
       */
      beanFactory.setBeanExpressionResolver(new StandardBeanExpressionResolver(beanFactory.getBeanClassLoader()));
   }
   // 为 beanFactory 增加了一个默认的 propertyEditor，这个主要是对 bean 的属性等设置管理的一个工具
   beanFactory.addPropertyEditorRegistrar(new ResourceEditorRegistrar(this, getEnvironment()));
   // 添加 Bean 增强器
   beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this));
   // 设置忽略自动装配的接口
   beanFactory.ignoreDependencyInterface(EnvironmentAware.class);
   beanFactory.ignoreDependencyInterface(EmbeddedValueResolverAware.class);
   beanFactory.ignoreDependencyInterface(ResourceLoaderAware.class);
   beanFactory.ignoreDependencyInterface(ApplicationEventPublisherAware.class);
   beanFactory.ignoreDependencyInterface(MessageSourceAware.class);
   beanFactory.ignoreDependencyInterface(ApplicationContextAware.class);
   beanFactory.ignoreDependencyInterface(ApplicationStartupAware.class);
   // 设置自动装配的特殊规则
   beanFactory.registerResolvableDependency(BeanFactory.class, beanFactory);
   beanFactory.registerResolvableDependency(ResourceLoader.class, this);
   beanFactory.registerResolvableDependency(ApplicationEventPublisher.class, this);
   beanFactory.registerResolvableDependency(ApplicationContext.class, this);
   // 添加 Bean 增强器
   beanFactory.addBeanPostProcessor(new ApplicationListenerDetector(this));
   // 增加对 AspectJ 的支持
   if (!NativeDetector.inNativeImage() && beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) {
      beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory));
      // 为类型匹配设置临时类加载器
      beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader()));
   }
   // 添加默认的系统环境 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());
   }
   if (!beanFactory.containsLocalBean(APPLICATION_STARTUP_BEAN_NAME)) {
      beanFactory.registerSingleton(APPLICATION_STARTUP_BEAN_NAME, getApplicationStartup());
   }
}