private void initialize(Object[] sources) {

         if (sources != null && sources.length > 0) {

             this.sources.addAll(Arrays.asList(sources));

         }
　　　　　　　//判断当前是否是web应用

         this.webEnvironment = deduceWebEnvironment();
　　　　　　　//从类路径下找到META-INF/spring

         setInitializers((Collection) getSpringFactoriesInstances(

                 ApplicationContextInitializer.class));

         setListeners((Collection) getSpringFactoriesInstances(ApplicationListener.class));

         this.mainApplicationClass = deduceMainApplicationClass();

     }

        StopWatch stopWatch = new StopWatch();

        stopWatch.start();

        ConfigurableApplicationContext context = null;

        configureHeadlessProperty();
　　　　　　//获取liestener 从类路径下META-INF/spring.factoise下获取

        SpringApplicationRunListeners listeners = getRunListeners(args);
　　　　　　//回调starting方法

        listeners.started();

        try {
　　　　　　　　//封装命令行参数

            ApplicationArguments applicationArguments = new DefaultApplicationArguments(

                    args);

            context = createAndRefreshContext(listeners, applicationArguments);

            afterRefresh(context, applicationArguments);

            listeners.finished(context, null);

            stopWatch.stop();

            if (this.logStartupInfo) {

                new StartupInfoLogger(this.mainApplicationClass)

                        .logStarted(getApplicationLog(), stopWatch);

            }

            return context;

        }

        catch (Throwable ex) {

            handleRunFailure(context, listeners, ex);

            throw new IllegalStateException(ex);

        }