SpringBoot源码解析

public ConfigurableApplicationContext run(String... args) {
   
   		//设置启动时间
        long startTime = System.nanoTime();
    	//设置上下文
        DefaultBootstrapContext bootstrapContext = this.createBootstrapContext();
        ConfigurableApplicationContext context = null;
        this.configureHeadlessProperty();
    	//创建监听器并从中获取符合监听事件的几个监听器
        SpringApplicationRunListeners listeners = this.getRunListeners(args);
        listeners.starting(bootstrapContext, this.mainApplicationClass);

        try {
   
            //配置命令行参数
            ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);
            //准备应用程序运行的环境
            ConfigurableEnvironment environment = this.prepareEnvironment(listeners, bootstrapContext, applicationArguments);
            this.configureIgnoreBeanInfo(environment);
            //打印banner(也就是那个p用没有的图标)
            Banner printedBanner = this.printBanner(environment);
            context = this.createApplicationContext();
            context.setApplicationStartup(this.applicationStartup);
            //prepareContext和refreshContext是自动装配的核心方法 而且这个refreshContext方法就是spring中的refresh()方法 使用的就是里面的beanFactoryPostProcessor()来实现的自动装配
            this.prepareContext(bootstrapContext, context, environment, listeners, applicationArguments, printedBanner);
            this.refreshContext(context);
            this.afterRefresh(context, applicationArguments);
            Duration timeTakenToStartup = Duration.ofNanos(System.nanoTime() - startTime);
            //发布应用上下文启动,执行runner()运行器
            if (this.logStartupInfo) {
   
                (new StartupInfoLogger(this.mainApplicationClass)).logStarted(this.getApplicationLog(), timeTakenToStartup);
            }

            listeners.started(context, timeTakenToStartup);
            this.callRunners(context, applicationArguments);
        } catch (Throwable var12) {
   
            this.handleRunFailure(context, var12, listeners);
            throw new IllegalStateException(var12);
        }
    
		//发布应用上下文就绪并返回
        try {
   
            Duration timeTakenToReady = Duration.ofNanos(System.nanoTime() - startTime);
            listeners.ready(context, timeTakenToReady);
            return context;
        } catch (Throwable var11) {
   
            this.handleRunFailure(context, var11, (SpringApplicationRunListeners)null);
            throw new IllegalStateException(var11);
        }
    }