spring容器的功能扩展

忘是亡心i 2021-11-22 04:44 310阅读 0赞

容器的扩展功能主要实现为：

org.springframework.context.support.AbstractApplicationContext.refresh()

public void refresh() throws BeansException, IllegalStateException {
            synchronized (this.startupShutdownMonitor) {
                // 准备刷新的上下文环境
                // Prepare this context for refreshing.
                prepareRefresh();
                
                // 初始化BeanFactory，并进行xml文件读取
                // Tell the subclass to refresh the internal bean factory.
                ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();
    
                // 对BeanFactory进行各种功能填充
                // Prepare the bean factory for use in this context.
                prepareBeanFactory(beanFactory);
    
                try {
                    // 子类覆盖方法做额外的处理
                    // Allows post-processing of the bean factory in context subclasses.
                    postProcessBeanFactory(beanFactory);
    
                    // 激活各种BeanFactory处理器
                    // Invoke factory processors registered as beans in the context.
                    invokeBeanFactoryPostProcessors(beanFactory);
    
                    // 注册拦截bean创建的bean处理器，这里只是注册，真正的调用时在getBean时候
                    // Register bean processors that intercept bean creation.
                    registerBeanPostProcessors(beanFactory);
    
                    // 为上下文初始化Message源，即不同语言的消息体，国际化处理
                    // Initialize message source for this context.
                    initMessageSource();
    
                    // 初始化应用消息广播器，并放入ApplicationEventMulticaster中
                    // Initialize event multicaster for this context.
                    initApplicationEventMulticaster();
    
                    // 留给子类来初始化其他的bean
                    // Initialize other special beans in specific context subclasses.
                    onRefresh();
    
                    // 在所有注册的bean中查找listener bean，注册到消息广播器中
                    // Check for listener beans and register them.
                    registerListeners();
    
                    // 初始化剩下的单实例（非延迟加载的）
                    // Instantiate all remaining (non-lazy-init) singletons.
                    finishBeanFactoryInitialization(beanFactory);
    
                    // 完成刷新过程，通知生命周期处理器lifecycleProcessor刷新过程，同时发出ContextRefreshEvent通知别人
                    // 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;
                }
            }
        }

参考：spring源码深度解析

转载于:https://www.cnblogs.com/xkzhangsanx/p/11183912.html