ioc source code analysis (three) ---- refresh method of prepareBeanFactory

After refreshing BeanFactory, started prepareBeanFactory method. This method is characterized in the context of the standard configuration of the plant.

protected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) {

   //设置beanFactory的classLoader为当前context的classLoader
   beanFactory.setBeanClassLoader(getClassLoader());

   //设置beanFactory的表达式语言处理器，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()));

   //添加属性编辑器，更准确应该是属性转换器，比如从String到Date类型的 转化
   beanFactory.addPropertyEditorRegistrar(new ResourceEditorRegistrar(this, getEnvironment()));

   //添加后置处理器
   beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this));

   //忽略自动装配
   beanFactory.ignoreDependencyInterface(EnvironmentAware.class);
   beanFactory.ignoreDependencyInterface(EmbeddedValueResolverAware.class);
   beanFactory.ignoreDependencyInterface(ResourceLoaderAware.class);
   beanFactory.ignoreDependencyInterface(ApplicationEventPublisherAware.class);
   beanFactory.ignoreDependencyInterface(MessageSourceAware.class);
   beanFactory.ignoreDependencyInterface(ApplicationContextAware.class);
   
   //设置几个自动装配规则，例如如果是BeanFactory则注入beanFactory
   //如果是ResourceLoader，ApplicationEventPublisher，ApplicationContext注入当前对象
   beanFactory.registerResolvableDependency(BeanFactory.class, beanFactory);
   beanFactory.registerResolvableDependency(ResourceLoader.class, this);
   beanFactory.registerResolvableDependency(ApplicationEventPublisher.class, this);
   beanFactory.registerResolvableDependency(ApplicationContext.class, this);

   
   // 如果包含LoadTimeWeaver，（AspectJ支持）
   if (beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) {
   
      //添加后置处理器
      beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory));

      // Set a temporary ClassLoader for type matching.
      beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader()));
   }
   
   // 这里的属性都是系统属性，我们前面看到过，但是都是单独存在的并没有注入到容器中
   //这里把系统属性注入到容器中
   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());
   }

}