spring-boot源码分析

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.resourceLoader = resourceLoader;
        Assert.notNull(primarySources, "PrimarySources must not be null");
        this.primarySources = new LinkedHashSet(Arrays.asList(primarySources));
    	/**
    	* 推断项目类型
    	* 主要有三种类型
    	* NONE:非web项目
    	* SERVlET:标准的servlet web项目
    	* 还有REACTIVE:WEBFLUX等
    	**/
        this.webApplicationType = WebApplicationType.deduceFromClasspath();
       /**
       * 判断完成项目类型
       * 调用getSpringFactoriesInstances
       * 自动配置
       **/
    this.setInitializers(this.getSpringFactoriesInstances(ApplicationContextInitializer.class));
        this.setListeners(this.getSpringFactoriesInstances(ApplicationListener.class));
        this.mainApplicationClass = this.deduceMainApplicationClass();
    }