【ApplicationListener】Springboot各类事件监听器

Springboot中SpringApplicationEvent的种类

如下图:

【ApplicationListener】Springboot各类事件监听器

主要包括6种:

  1. ApplicationEnvironmentPreparedListener
  2. ApplicationFailedListener
  3. ApplicationPreparedListener
  4. ApplicationReadyListener
  5. ApplicationStartingListener
  6. SpringApplicationListener

各监听器的启动顺序

如下是debug输出结果:

// 省略了部分
Connected to the target VM, address: '127.0.0.1:52000', transport: 'socket'
2017-09-28 16:53:27.273 INFO 6960 --- [ main] c.s.listeners.SpringApplicationListener : 监听器事件 【SpringApplicationEvent】
2017-09-28 16:53:27.277 INFO 6960 --- [ main] l.ApplicationEnvironmentPreparedListener : 监听器事件 【ApplicationEnvironmentPreparedEvent】 . ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v1.5.7.RELEASE) 2017-09-28 16:53:27.359 INFO 6960 --- [ main] c.s.ApplicationlistenerApplication : Starting ApplicationlistenerApplication on LIULIN-PC with PID 6960 (D:\workspace\SpringBootStudy\applicationlistener\target\classes started by liulin in D:\workspace\SpringBootStudy)
2017-09-28 16:53:27.359 INFO 6960 --- [ main] c.s.ApplicationlistenerApplication : No active profile set, falling back to default profiles: default
2017-09-28 16:53:27.403 INFO 6960 --- [ main] c.s.l.ApplicationPreparedListener : 监听器事件 【ApplicationPreparedEvent】
2017-09-28 16:53:27.403 INFO 6960 --- [ main] c.s.listeners.SpringApplicationListener : 监听器事件 【SpringApplicationEvent】
2017-09-28 16:53:27.406 INFO 6960 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@2f465398: startup date [Thu Sep 28 16:53:27 CST 2017]; root of context hierarchy
2017-09-28 16:53:28.878 INFO 6960 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-09-28 16:53:28.887 INFO 6960 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2017-09-28 16:53:28.888 INFO 6960 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.20
2017-09-28 16:53:28.952 INFO 6960 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2017-09-28 16:53:28.952 INFO 6960 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1549 ms
2017-09-28 16:53:29.070 INFO 6960 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]
2017-09-28 16:53:29.074 INFO 6960 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-09-28 16:53:29.074 INFO 6960 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-09-28 16:53:29.074 INFO 6960 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-09-28 16:53:29.074 INFO 6960 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2017-09-28 16:53:29.105 INFO 6960 --- [ main] com.ssslinppp.service.DemoServiceA : 初始化实例:DemoServiceA
2017-09-28 16:53:29.107 INFO 6960 --- [ main] com.ssslinppp.service.DemoServiceB : 初始化实例:DemoServiceB
2017-09-28 16:53:29.327 INFO 6960 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@2f465398: startup date [Thu Sep 28 16:53:27 CST 2017]; root of context hierarchy
2017-09-28 16:53:29.382 INFO 6960 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-09-28 16:53:29.382 INFO 6960 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-09-28 16:53:29.420 INFO 6960 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-28 16:53:29.420 INFO 6960 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-28 16:53:29.451 INFO 6960 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-09-28 16:53:29.626 INFO 6960 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2017-09-28 16:53:29.668 INFO 6960 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-09-28 16:53:29.671 INFO 6960 --- [ main] c.s.listeners.ApplicationReadyListener : 监听器事件 【ApplicationReadyEvent】 : ApplicationReadyListener
2017-09-28 16:53:29.671 INFO 6960 --- [ main] c.s.listeners.SpringApplicationListener : 监听器事件 【SpringApplicationEvent】
2017-09-28 16:53:29.672 INFO 6960 --- [ main] c.s.ApplicationlistenerApplication : Started ApplicationlistenerApplication in 2.577 seconds (JVM running for 3.022)

从上面可以看出,顺序如下:

  1. SpringApplicationEvent
  2. ApplicationEnvironmentPreparedEvent :可以通过ConfigurableEnvironment实例对象来修改 以及 获取默认的环境信息。
  3. 初始化图标(banner)
  4. ApplicationPreparedEvent :这个时候spring容器中的bean还没有被完全的加载,如果通过ConfigurableApplicationContext获取bean会报错的
  5. SpringApplicationEvent
  6. 映射基本的servlet URL: [/][/*]
  7. 初始化Spring容器中的beans
  8. ApplicationReadyEvent :可以通过ApplicationReadyEvent获取ConfigurableApplicationContext,然后通过ConfigurableApplicationContext 获取bean的信息

各种SpringApplicationEvent的主要用途示例

上一篇:Erlang 虚拟机内的内存管理(Lukas Larsson演讲听写稿)


下一篇:在Windows服务中托管 ASP.NET Core的坑