public static ConfigurableApplicationContext run(Class<?> primarySource, String[] args) {
    return new SpringApplication(primarySource).run(args);
}

StopWatch stopWatch = new StopWatch();
stopWatch.start();

SpringApplicationRunListeners listeners = getRunListeners(args);
listeners.starting(); // 發(fā)布ApplicationStartingEvent

ConfigurableEnvironment environment = prepareEnvironment(listeners, applicationArgs);

graph TD
    A[創(chuàng)建Environment對象] --> B[加載配置源]
    B --> C[解析Profile配置]
    C --> D[轉(zhuǎn)換配置屬性]
    D --> E[發(fā)布ApplicationEnvironmentPreparedEvent]

Banner printedBanner = printBanner(environment);

context = createApplicationContext();

protected ConfigurableApplicationContext createApplicationContext() {
    return switch (this.webApplicationType) {
        case SERVLET -> new AnnotationConfigServletWebServerApplicationContext();
        case REACTIVE -> new AnnotationConfigReactiveWebServerApplicationContext();
        default -> new AnnotationConfigApplicationContext(); // 非Web應用
    };
}

prepareContext(context, environment, listeners, appArgs, printedBanner);

refreshContext(context); // 內(nèi)部調(diào)用Spring的refresh()

public void refresh() {
    // 1. 準備刷新
    prepareRefresh();
    // 2. 獲取BeanFactory
    ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();
    // 3. 準備BeanFactory
    prepareBeanFactory(beanFactory);
    try {
        // 4. 后置處理BeanFactory
        postProcessBeanFactory(beanFactory);
        // 5. ★★★ 執(zhí)行BeanFactoryPostProcessor（自動配置入口）
        invokeBeanFactoryPostProcessors(beanFactory);
        // 6. 注冊BeanPostProcessor
        registerBeanPostProcessors(beanFactory);
        // 7. 初始化消息源
        initMessageSource();
        // 8. 初始化事件廣播器
        initApplicationEventMulticaster();
        // 9. ★ Web容器啟動關鍵步驟
        onRefresh();
        // 10. 注冊監(jiān)聽器
        registerListeners();
        // 11. ★★★ 實例化所有非延遲單例Bean
        finishBeanFactoryInitialization(beanFactory);
        // 12. 完成刷新
        finishRefresh();
    } catch (BeansException ex) {
        // 異常處理...
    }
}

protected void invokeBeanFactoryPostProcessors(ConfigurableListableBeanFactory beanFactory) {
    PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(
        beanFactory, getBeanFactoryPostProcessors());
    // 這里會處理@SpringBootApplication->加載自動配置類
}

protected void onRefresh() {
    super.onRefresh();
    try {
        createWebServer(); // 啟動Tomcat/Jetty
    } catch (Throwable ex) {
        throw new ApplicationContextException("Unable to start web server", ex);
    }
}

protected void finishBeanFactoryInitialization(ConfigurableListableBeanFactory beanFactory) {
    // 初始化所有非延遲單例Bean
    beanFactory.preInstantiateSingletons();
}

afterRefresh(context, appArgs);

stopWatch.stop();
listeners.started(context); // ApplicationStartedEvent
callRunners(context, appArgs); // 執(zhí)行ApplicationRunner/CommandLineRunner
listeners.running(context); // ApplicationReadyEvent

private void callRunners(ApplicationContext context, ApplicationArguments args) {
    List<Object> runners = new ArrayList<>();
    runners.addAll(context.getBeansOfType(ApplicationRunner.class).values());
    runners.addAll(context.getBeansOfType(CommandLineRunner.class).values());
    AnnotationAwareOrderComparator.sort(runners);
    for (Object runner : runners) {
        if (runner instanceof ApplicationRunner) {
            ((ApplicationRunner) runner).run(args);
        }
        if (runner instanceof CommandLineRunner) {
            ((CommandLineRunner) runner).run(args.getSourceArgs());
        }
    }
}

graph TD
    A[SpringApplication.run] --> B[啟動計時器]
    B --> C[初始化監(jiān)聽器]
    C --> D[發(fā)布StartingEvent]
    D --> E[準備Environment]
    E --> F[打印Banner]
    F --> G[創(chuàng)建上下文]
    G --> H[預處理上下文]
    H --> I[refreshContext核心]
    I --> J[后置處理]
    J --> K[發(fā)布StartedEvent]
    K --> L[執(zhí)行Runner]
    L --> M[發(fā)布ReadyEvent]