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	public ConfigurableApplicationContext run(String... args) {
		StopWatch stopWatch = new StopWatch();
		stopWatch.start();
		ConfigurableApplicationContext context = null;
		Collection<SpringBootExceptionReporter> exceptionReporters = new ArrayList<>();
        //awt应用相关
		configureHeadlessProperty();
        //获取SpringApplicationRunListeners
        ////从类路径下META-INFO/spring.factories获取的所有Listeners  目前为1个
		SpringApplicationRunListeners listeners = getRunListeners(args);
        //回调所有的SpringApplicationRunListeners.starting()方法
		listeners.starting();
		try {
            //封装命令行参数
			ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);
			//准备环境
            ConfigurableEnvironment environment = prepareEnvironment(listeners, applicationArguments);
			//创建环境完成后回调所有的SpringApplicationRunListeners.environmentPrepared()方法表示环境准备完成
            configureIgnoreBeanInfo(environment);
            //打印Banner
			Banner printedBanner = printBanner(environment);
            //创建ApplicationContext IOC容器  根据创建SpringApplication对象时判断的webApplicationType类型来创建
			//从这里来决定创建的是web的ioc还是普通的ioc
            context = createApplicationContext();
            ////根据 ConfigurableApplicationContext 获取到 ConfigurableApplicationContext相关实例
			exceptionReporters = getSpringFactoriesInstances(SpringBootExceptionReporter.class,
					new Class[] { ConfigurableApplicationContext.class }, context);
            //准备上下文 
            //1.将Environment保存到IOC
            //2.回调创建SpringApplication对象时保存的所有的ApplicationContextInitializer的initialize()方法 
            //3.回调创建SpringApplication对象时保存的所有的SpringApplicationRunListeners.contextPrepared()方法
			//4.prepareContext运行完成以后回调所有的SpringApplicationRunListeners.contextLoaded()方法
            prepareContext(context, environment, listeners, applicationArguments, printedBanner);
			//刷新容器,IOC初始化的过程,加载IOC容器内所有的组件(配置类,bean,组件,自动配置等)如果是web应用还会创建嵌入式的tomcat
            refreshContext(context);
            //从IOC容器中获取所有的ApplicationRunner和CommandlineRunner
            //ApplicationRunner先于CommandlineRunner回调
			afterRefresh(context, applicationArguments);
			stopWatch.stop();
			if (this.logStartupInfo) {
				new StartupInfoLogger(this.mainApplicationClass).logStarted(getApplicationLog(), stopWatch);
			}
            //所有的SpringApplicationRunListeners.started()方法
			listeners.started(context);
            //如果有 ApplicationRunner || CommandLineRunner 相关的bean 启动它
			callRunners(context, applicationArguments);
		}
		catch (Throwable ex) {
            //如果Spring启动失败 打印信息
			handleRunFailure(context, ex, exceptionReporters, listeners);
			throw new IllegalStateException(ex);
		}

		try {
            //所有的SpringApplicationRunListeners.running()方法
			listeners.running(context);
		}
		catch (Throwable ex) {
			handleRunFailure(context, ex, exceptionReporters, null);
			throw new IllegalStateException(ex);
		}
        //整个SpringBoot应用启动以后返回启动的IOC容器,里面包含所有的组件
		return context;
	}