SpringBoot启动应用及回调监听原理解析

 public static void main(String[] args) { SpringApplication.run(SpringBootRunApplication.class, args); }

 public static ConfigurableApplicationContext run(Class[] primarySources, String[] args) { return (new SpringApplication(primarySources)).run(args); }　　

 public SpringApplication(ResourceLoader resourceLoader, Class... primarySources) { this.sources = new LinkedHashSet(); this.bannerMode = Mode.CONSOLE; this.logStartupInfo = true; this.addCommandLineProperties = true; this.addConversionService = true; this.headless = true; this.registerShutdownHook = true; this.additionalProfiles = new HashSet(); this.isCustomEnvironment = false; this.lazyInitialization = false; this.resourceLoader = resourceLoader; Assert.notNull(primarySources, "PrimarySources must not be null"); this.primarySources = new LinkedHashSet(Arrays.asList(primarySources)); this.webApplicationType = WebApplicationType.deduceFromClasspath(); this.setInitializers(this.getSpringFactoriesInstances(ApplicationContextInitializer.class)); this.setListeners(this.getSpringFactoriesInstances(ApplicationListener.class)); this.mainApplicationClass = this.deduceMainApplicationClass(); }

 this.setInitializers(this.getSpringFactoriesInstances(ApplicationContextInitializer.class)); this.setListeners(this.getSpringFactoriesInstances(ApplicationListener.class));

 public ConfigurableApplicationContext run(String... args) { StopWatch stopWatch = new StopWatch(); stopWatch.start(); // IOC容器 ConfigurableApplicationContext context = null; Collection exceptionReporters = new ArrayList(); this.configureHeadlessProperty(); // 读取META-INF/spring.factories文件获得SpringApplicationRunListener的实现类集合 SpringApplicationRunListeners listeners = this.getRunListeners(args); // 监听开始，回调所有SpringApplicationRunListener的starting()方法 listeners.starting(); Collection exceptionReporters; try { ApplicationArguments applicationArguments = new DefaultApplicationArguments(args); // 监听配置环境准备好了，回调所有SpringApplicationRunListener的environmentPrepared()方法 ConfigurableEnvironment environment = this.prepareEnvironment(listeners, applicationArguments); this.configureIgnoreBeanInfo(environment); Banner printedBanner = this.printBanner(environment); // 创建IOC容器 context = this.createApplicationContext(); exceptionReporters = this.getSpringFactoriesInstances(SpringBootExceptionReporter.class, new Class[]{ConfigurableApplicationContext.class}, context); // 回调ApplicationContextInitializer的initialize()方法，回调SpringApplicationRunListener的contextPrepared()方法 // 回调SpringApplicationRunListener的contextLoaded()方法 this.prepareContext(context, environment, listeners, applicationArguments, printedBanner); // 刷新IOC容器，注入组件 this.refreshContext(context); this.afterRefresh(context, applicationArguments); stopWatch.stop(); if (this.logStartupInfo) { (new StartupInfoLogger(this.mainApplicationClass)).logStarted(this.getApplicationLog(), stopWatch); } // 回调SpringApplicationRunListener的started()方法 listeners.started(context); // 从IOC容器中获得ApplicationRunner、CommandLineRunner的所有组件，回调ApplicationRunner、CommandLineRunner的run()方法 this.callRunners(context, applicationArguments); } catch (Throwable var10) { this.handleRunFailure(context, var10, exceptionReporters, listeners); throw new IllegalStateException(var10); } try { // 回调SpringApplicationRunListener的running()方法 listeners.running(context); return context; } catch (Throwable var9) { this.handleRunFailure(context, var9, exceptionReporters, (SpringApplicationRunListeners)null); throw new IllegalStateException(var9); } }