public void refresh() throws BeansException, IllegalStateException {

    // Prepare this context for refreshing.

    prepareRefresh();

    // Tell the subclass to refresh the internal bean factory.

    // 1. 创建一个 BeanFactory 的实例（DefaultListableBeanFactory）

    // 2. 加载bean的定义 BeanDefinition，并注册到 beanFactory 中

    // loadBeanDefinitions(beanFactory) --> registerBeanDefinitions()

    ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();

    // Prepare the bean factory for use in this context.

    // 给 beanFactory 做上些前期配置：

    // 1. 添加 BeanPostProcessor

    // 2. 注册一些可以解析的依赖和 bean，如：BeanFactory, ApplicationContext

    prepareBeanFactory(beanFactory);

    // Allows post-processing of the bean factory in context subclasses.

    // 允许子类对 beanFactory 对象做一些后置处理

    postProcessBeanFactory(beanFactory);

    // Invoke factory processors registered as beans in the context.

    // 调用 beanFactoryPostProcessor，允许用户对 beanFactory 做修改（扩展点），比如添加、修改或删除 beanFactory 中注册的 BeanDefinition 等

    // 按顺序调用：PriorityOrdered 类型的 --> Ordered 类型的 --> the rest

    invokeBeanFactoryPostProcessors(beanFactory);

    // Register bean processors that intercept bean creation.

    // 注册 beanPostProcessor 到 beanFactory 中

    registerBeanPostProcessors(beanFactory);

    // Initialize message source for this context.

    initMessageSource();

    // Initialize event multicaster for this context.

    // 初始化事件广播器

    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.

    // 完成 beanFactory 的初始化：解析 bean 的依赖，完成 bean 实例的初始化

    finishBeanFactoryInitialization(beanFactory);

    // Last step: publish corresponding event.

    finishRefresh();

}

实例化 -> 属性赋值 -> 初始化 -> 销毁

// 忽略了无关代码

protected Object doCreateBean(final String beanName, final RootBeanDefinition mbd, final @Nullable Object[] args) throws BeanCreationException {

    // Instantiate the bean.

    BeanWrapper instanceWrapper = null;

    if (instanceWrapper == null) {

        // 实例化阶段！

        instanceWrapper = createBeanInstance(beanName, mbd, args);

    }

    // Initialize the bean instance.

    Object exposedObject = bean;

    try {

        // 属性赋值阶段！填充 bean 属性：这一步主要是对bean的依赖属性进行注入(@Autowired)

        populateBean(beanName, mbd, instanceWrapper);

        // 初始化阶段！

        exposedObject = initializeBean(beanName, exposedObject, mbd);

    }

}

PriorityOrdered 类型的 --> Ordered 类型的 --> the rest