Spring核心方法refresh的使用解析

prepareRefresh()
obtainFreshBeanFactory()
prepareBeanFactory(beanFactory)
postProcessBeanFactory(beanFactory)
invokeBeanFactoryPostProcessors(beanFactory)
registerBeanPostProcessors(beanFactory)
initMessageSource()
initApplicationEventMulticaster()
onRefresh()
registerListeners()
finishBeanFactoryInitialization(beanFactory)
finishRefresh()

// 设置启动时间
this.startupDate = System.currentTimeMillis();
// 1交给子类实现，初始化属性源
initPropertySources();
// 验证所有标记为必须的属性
getEnvironment().validateRequiredProperties();

System.out.println("开始校验自定义配置");
getEnvironment().setRequiredProperties("my-name");

// 刷新 BeanFactory
refreshBeanFactory();
// 获取 getBeanFactory
return getBeanFactory();

//创建 beanFactory
DefaultListableBeanFactory beanFactory = createBeanFactory();
// 指定序列化 id
beanFactory.setSerializationId(getId());
// 定制 beanFactory，设置相关属性，包括是否允许覆盖同名称的不同定义的对象以及循环依赖及设置 @Autowired 和 @Qualifier 注解解析器
customizeBeanFactory(beanFactory);
// 初始化 DocumentReader,并进行 XML 文件的读取及解析，生成 BeanDefinition
loadBeanDefinitions(beanFactory);

// 设置 beanFactory 的类加载器
beanFactory.setBeanClassLoader(getClassLoader());
// 设置支持表达式解析器
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()));
// 添加部分BeanPostProcessor【ApplicationContextAwareProcessor】
beanFactory.addBeanPostProcessor(new ApplicationContextAwareProcessor(this));
//设置忽略的自动装配的接口EnvironmentAware、EmbeddedValueResolverAware、xxx；
//这些接口的实现类不能通过类型来自动注入
beanFactory.ignoreDependencyInterface(EnvironmentAware.class);
beanFactory.ignoreDependencyInterface(EmbeddedValueResolverAware.class);
beanFactory.ignoreDependencyInterface(ResourceLoaderAware.class);
beanFactory.ignoreDependencyInterface(ApplicationEventPublisherAware.class);
beanFactory.ignoreDependencyInterface(MessageSourceAware.class);
beanFactory.ignoreDependencyInterface(ApplicationContextAware.class);
// 注册可以解析的自动装配；我们能直接在任何组件中自动注入
beanFactory.registerResolvableDependency(BeanFactory.class, beanFactory);
beanFactory.registerResolvableDependency(ResourceLoader.class, this);
beanFactory.registerResolvableDependency(ApplicationEventPublisher.class, this);
beanFactory.registerResolvableDependency(ApplicationContext.class, this);
// 增加对 AspectJ 的支持
if (beanFactory.containsBean(LOAD_TIME_WEAVER_BEAN_NAME)) {
    beanFactory.addBeanPostProcessor(new LoadTimeWeaverAwareProcessor(beanFactory));
    // Set a temporary ClassLoader for type matching.
    beanFactory.setTempClassLoader(new ContextTypeMatchClassLoader(beanFactory.getBeanClassLoader()));
}
// 环境信息ConfigurableEnvironment
if (!beanFactory.containsLocalBean(ENVIRONMENT_BEAN_NAME)) {
    beanFactory.registerSingleton(ENVIRONMENT_BEAN_NAME, getEnvironment());
}
// 系统属性，systemProperties【Map<String, Object>】
if (!beanFactory.containsLocalBean(SYSTEM_PROPERTIES_BEAN_NAME)) {
    beanFactory.registerSingleton(SYSTEM_PROPERTIES_BEAN_NAME, getEnvironment().getSystemProperties());
}
// 系统环境变量systemEnvironment【Map<String, Object>】
if (!beanFactory.containsLocalBean(SYSTEM_ENVIRONMENT_BEAN_NAME)) {
    beanFactory.registerSingleton(SYSTEM_ENVIRONMENT_BEAN_NAME, getEnvironment().getSystemEnvironment());
}

// 执行BeanFactoryPostProcessor的方法
PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(beanFactory, getBeanFactoryPostProcessors());

// 把这件事委托给 PostProcessorRegistrationDelegate 来处理
PostProcessorRegistrationDelegate.registerBeanPostProcessors(beanFactory, this);

// 1. 获取所有的 Bean 后置处理器的名字
String[] postProcessorNames = beanFactory.getBeanNamesForType(BeanPostProcessor.class, true, false);
// 2. 对 Bean 后置处理器分类
List<BeanPostProcessor> priorityOrderedPostProcessors = new ArrayList<>();
List<BeanPostProcessor> internalPostProcessors = new ArrayList<>();
List<String> orderedPostProcessorNames = new ArrayList<>();
List<String> nonOrderedPostProcessorNames = new ArrayList<>();
// 3. 注册 Bean 后置处理器
registerBeanPostProcessors(beanFactory, priorityOrderedPostProcessors);
registerBeanPostProcessors(beanFactory, orderedPostProcessors);
registerBeanPostProcessors(beanFactory, nonOrderedPostProcessors);
registerBeanPostProcessors(beanFactory, internalPostProcessors);
// 4. 注册 ApplicationListener 探测器
beanFactory.addBeanPostProcessor(new ApplicationListenerDetector(applicationContext));

// 1. 添加指定的监听器
for (ApplicationListener<?> listener : getApplicationListeners()) {
    getApplicationEventMulticaster().addApplicationListener(listener);
}
// 2. 获取所有实现 ApplicationListener 的广播器,并添加
String[] listenerBeanNames = getBeanNamesForType(ApplicationListener.class, true, false);
for (String listenerBeanName : listenerBeanNames) {
    getApplicationEventMulticaster().addApplicationListenerBean(listenerBeanName);
}

// 1. 冻结所有的 bean，已经注册的 bean 定义将不会被修改或任何进一步的处理
beanFactory.freezeConfiguration();
// 2. 实例化所有剩余的非懒加载的 bean
beanFactory.preInstantiateSingletons();

// 3.获取容器中所有 beanDefinition 的名称
List<String> beanNames = new ArrayList<>(this.beanDefinitionNames);
for (String beanName : beanNames) {
    // 根据 beanName 获取 BeanDefinition
    RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
    // 不是抽象的 && 是单例的 && 不是懒加载的
    if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {
        if (isFactoryBean(beanName)) {
            // 如果是 FactoryBean，就先获取 FactoryBean 实例
            Object bean = getBean(FACTORY_BEAN_PREFIX + beanName);
            if (bean instanceof FactoryBean) {
                …………
            }
        }
        else {
            // 如果不是 FactoryBean,就直接获取 Bean
            getBean(beanName);
        }
    }
}

// 清除上下文资源缓存（如扫描中的ASM元数据） scanning).
clearResourceCaches();
// 初始化上下文的生命周期处理器，并刷新（找出Spring容器中实现了Lifecycle接口的bean并执行start()方法）
initLifecycleProcessor();
getLifecycleProcessor().onRefresh();
// 发布ContextRefreshedEvent事件告知对应的ApplicationListener进行响应的操作
publishEvent(new ContextRefreshedEvent(this));