Tips: 以下内容根据源码中的注解翻译

SpringApplication

SpringApplication可用来从一个Java main方法引导和启动一个Spring应用。默认情况下，SpringApplication按照以下步骤引导你的应用：

• 创建一个合适的ApplicationContext（依赖于你的classpath）
• 注册一个CommandLinePropertySource，用来将命令行参数暴露为Spring属性
• 刷新应用上下文，加载所有单例beans
• 触发所有的CommandLineRunner beans

在绝大多数情况下，可以直接在main方法中调用静态方法 SpringApplication.run(Class, String[])来引导你的应用：

@Configuration   @EnableAutoConfiguration   public class MyApplication  {       // ... Bean definitions       public static void main(String[] args) {       SpringApplication.run(MyApplication.class, args);     }   }

想要使用更多高级配置，可以创建一个SpringApplication实例并自定义，然后调用实例的run方法：

public static void main(String[] args) {     SpringApplication application = new SpringApplication(MyApplication.class);     // ... customize application settings here     application.run(args)   }

SpringApplications可以从各种不同的资源读入beans。通常建议用一个单独的@Configuration类来引导你的应用，尽管如此，你也可以从以下资源读入beans：

• 完全限定的类名，将被AnnotatedBeanDefinitionReader加载
• XML配置文件的路径，将被XmlBeanDefintionReader加载，或者是groovy脚本，将被GroovyBeanDefintionReader加载
• 包名，将被ClassPathBeanDefinitioinReader扫描

Configuration属性会被绑定到SpringApplication。这让动态设置SpringApplication属性成为可能，如附加的资源("spring.main.sources" - 一个CSV列表) ，表示一个web环境的标识("spring.main.web-application-type=none" )，或 关闭banner的标记("spring.main.banner-mode=off")

源码中的注解：

Class that can be used to bootstrap and launch a Spring application from a Java main method. By default class will perform the following steps to bootstrap your application: Create an appropriate ApplicationContext instance (depending on your classpath) Register a CommandLinePropertySource to expose command line arguments as Spring properties Refresh the application context, loading all singleton beans Trigger any CommandLineRunner beans In most circumstances the static run(Class, String[]) method can be called directly from your main method to bootstrap your application:   @Configuration   @EnableAutoConfiguration   public class MyApplication  {       // ... Bean definitions       public static void main(String[] args) {       SpringApplication.run(MyApplication.class, args);     }   }    For more advanced configuration a SpringApplication instance can be created and customized before being run:   public static void main(String[] args) {     SpringApplication application = new SpringApplication(MyApplication.class);     // ... customize application settings here     application.run(args)   }    SpringApplications can read beans from a variety of different sources. It is generally recommended that a single @Configuration class is used to bootstrap your application, however, you may also set sources from: The fully qualified class name to be loaded by AnnotatedBeanDefinitionReader The location of an XML resource to be loaded by XmlBeanDefinitionReader, or a groovy script to be loaded by GroovyBeanDefinitionReader The name of a package to be scanned by ClassPathBeanDefinitionScanner Configuration properties are also bound to the SpringApplication. This makes it possible to set SpringApplication properties dynamically, like additional sources ("spring.main.sources" - a CSV list) the flag to indicate a web environment ("spring.main.web-application-type=none") or the flag to switch off the banner ("spring.main.banner-mode=off"). Since: 1.0.0 See Also: run(Class, String[]), run(Class[], String[]), SpringApplication(Class...)