Spring源码情操陶冶-AbstractApplicationContext

时间:2022-01-07 04:58:31

前言-阅读源码有利于陶冶情操,本文承接前文Spring源码情操陶冶-ContextLoader

约束:本文指定contextClass为默认的XmlWebApplicationContext

AbstractApplicationContext#refresh()

简单看下refresh()方法内罗列的一系列方法,代码清单如下

public void refresh() 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();
} catch (BeansException ex) {
// Destroy already created singletons to avoid dangling resources.
destroyBeans(); // Reset 'active' flag.
cancelRefresh(ex); // Propagate exception to caller.
throw ex;
}
}
}

针对上述的代码逻辑,为了避免代码的凌乱以及放在同篇文章文字过长,遂作如下链接导航

  • AbstractApplicationContext#prepareRefresh

    刷新准备工作,@prepareRefresh

  • AbstractApplicationContext#obtainFreshBeanFactory

    涉及解析spring配置文件并封装为BeanDefinition对象保存至beanFactory中,@obtainFreshBeanFactory

  • AbstractApplicationContext#prepareBeanFactory

    beanFactory的准备工作,设置context的属性配置,@prepareBeanFactory

  • AbstractApplicationContext#postProcessBeanFactory

    主要添加ServletContextAwareProcessor处理类,@postProcessBeanFactory

  • AbstractApplicationContext#invokeBeanFactoryPostProcessors

    执行BeanDefinitionRegistryPostProcessors/BeanFactoryPostProcessors相关beans,@invokeBeanFactoryPostProcessors

  • AbstractApplicationContext#registerBeanPostProcessors

    注册所有实现BeanPostProcessor的接口bean到beanFactory的内部属性beanPostProcessors集合中,@registerBeanPostProcessors

  • AbstractApplicationContext#initMessageSource

    初始化资源配置,@initMessageSource

  • AbstractApplicationContext#initApplicationEventMulticaster

    初始化ApplictionEventMulticaster广播事件类,@initApplicationEventMulticaster

  • AbstractApplicationContext#onRefresh

    初始化themeSource,@onRefresh

  • AbstractApplicationContext#registerListeners

    注册ApplicationListener beans到ApplictionEventMulticaster广播集合,@registerListeners

  • AbstractApplicationContext#finishBeanFactoryInitialization

    实例化所有的非lazy-init类型的beans,@finishBeanFactoryInitialization

  • AbstractApplicationContext#finishRefresh

    完成刷新,并执行ContextRefreshedEvent事件,该事件涉及spring mvc,@finishRefresh

结束语

阅读源码的目的是为了了解其运行的机制,但可能涵盖的内容过广,可以对有兴趣的地方进行深刻的源码追踪,并理解其中的代码设计,不为是一件快乐的事情