AbstractApplicationContext的refresh()方法是spring的核心谦炬，在其中完成了容器的初始化

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) {
                if (logger.isWarnEnabled()) {
                    logger.warn("Exception encountered during context initialization - " +
                            "cancelling refresh attempt: " + ex);
                }

                // Destroy already created singletons to avoid dangling resources.
                destroyBeans();

                // Reset 'active' flag.
                cancelRefresh(ex);

                // Propagate exception to caller.
                throw ex;
            }

            finally {
                // Reset common introspection caches in Spring's core, since we
                // might not ever need metadata for singleton beans anymore...
                resetCommonCaches();
            }
        }
    }

1、prepareRefresh();

容器刷新前的準(zhǔn)備，設(shè)置上下文狀態(tài)驳庭，獲取屬性兼丰，驗(yàn)證必要的屬性等

2、obtainFreshBeanFactory();

獲取新的beanFactory笆载，銷毀原有beanFactory扑馁、為每個(gè)bean生成BeanDefinition等

3、prepareBeanFactory(beanFactory);

配置標(biāo)準(zhǔn)的beanFactory宰译，設(shè)置ClassLoader檐蚜，設(shè)置SpEL表達(dá)式解析器，添加忽略注入的接口沿侈，添加bean闯第，添加bean后置處理器等

4、postProcessBeanFactory(beanFactory);

模板方法缀拭，此時(shí)咳短，所有的beanDefinition已經(jīng)加載填帽，但是還沒(méi)有實(shí)例化。
允許在子類中對(duì)beanFactory進(jìn)行擴(kuò)展處理咙好。比如添加ware相關(guān)接口自動(dòng)裝配設(shè)置篡腌，添加后置處理器等，是子類擴(kuò)展prepareBeanFactory(beanFactory)的方法

5勾效、invokeBeanFactoryPostProcessors(beanFactory);

實(shí)例化并調(diào)用所有注冊(cè)的beanFactory后置處理器（實(shí)現(xiàn)接口BeanFactoryPostProcessor的bean嘹悼，在beanFactory標(biāo)準(zhǔn)初始化之后執(zhí)行）。
例如:
PropertyPlaceholderConfigurer(處理占位符)

6层宫、registerBeanPostProcessors(beanFactory);

實(shí)例化和注冊(cè)beanFactory中擴(kuò)展了BeanPostProcessor的bean杨伙。
例如：
AutowiredAnnotationBeanPostProcessor(處理被@Autowired注解修飾的bean并注入)
RequiredAnnotationBeanPostProcessor(處理被@Required注解修飾的方法)
CommonAnnotationBeanPostProcessor(處理@PreDestroy、@PostConstruct萌腿、@Resource等多個(gè)注解的作用)等限匣。

7、initMessageSource();

初始化國(guó)際化工具類MessageSource

8毁菱、initApplicationEventMulticaster();

初始化事件廣播器

9米死、onRefresh();

模板方法，在容器刷新的時(shí)候可以自定義邏輯贮庞，不同的Spring容器做不同的事情峦筒。

10、registerListeners();

注冊(cè)監(jiān)聽(tīng)器贸伐，廣播early application events

11勘天、finishBeanFactoryInitialization(beanFactory);

實(shí)例化所有剩余的（非懶加載）單例
比如invokeBeanFactoryPostProcessors方法中根據(jù)各種注解解析出來(lái)的類，在這個(gè)時(shí)候都會(huì)被初始化捉邢。
實(shí)例化的過(guò)程各種BeanPostProcessor開(kāi)始起作用脯丝。

12、finishRefresh();

refresh做完之后需要做的其他事情伏伐。
清除上下文資源緩存（如掃描中的ASM元數(shù)據(jù)）
初始化上下文的生命周期處理器宠进，并刷新（找出Spring容器中實(shí)現(xiàn)了Lifecycle接口的bean并執(zhí)行start()方法）。
發(fā)布ContextRefreshedEvent事件告知對(duì)應(yīng)的ApplicationListener進(jìn)行響應(yīng)的操作