spring-mvc - 如何在 Spring Boot 中调试 MVC Controller URL 映射？

Question

我有一个运行 Kafka 和 JPA 的 Spring Boot 应用程序。我想添加一个管理页面，所以首先添加“spring-boot-starter-web”并添加 Controller 类。但是，当我启动我的应用程序时，我可以看到 Tomcat 服务器已经启动并且 dispatcherServlet 已初始化。

2018-04-13 18:25:29.495  INFO 5512 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$f5f4a697] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying) 
2018-04-13 18:25:30.584  INFO 5512 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2018-04-13 18:25:30.604  INFO 5512 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-04-13 18:25:30.607  INFO 5512 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.27
2018-04-13 18:25:33.052  INFO 5512 --- [ost-startStop-1] org.apache.jasper.servlet.TldScanner     : At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded
JARs during scanning can improve startup time and JSP compilation time.
2018-04-13 18:25:33.384  INFO 5512 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-04-13 18:25:33.384 DEBUG 5512 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Published root WebApplicationContext as ServletContext attribute with name [org.springframework.web.context.WebApplicationContext.ROOT] 
2018-04-13 18:25:33.385  INFO 5512 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization comp
leted in 6776 ms
2018-04-13 18:25:33.761  INFO 5512 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2018-04-13 18:25:33.768  INFO 5512 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'metricsFilter' to: [/*]

但我看不到 Controller 类与 handlerMapping 映射。来电 http://localhost:8080只给我一个服务器不可用的错误。

我该如何调试它？我已经检查了以下内容:

1. Controller 类位于主 Application.java 的子文件夹中文件。
2. Controller 有@Controller 注释。该包中的其他@Components 正在 Autowiring ，所以我确定该文件夹是已扫描。
3. 我在主类中扩展了 SpringBootServletInitializer 类。
4. 主类中有如下注解-@SpringBootApplication@Import(PersistenceConfig.class), @EnableKafka, @EnableCaching, @EnableWebMvc,@EnableAutoConfiguration(exclude = { KafkaAutoConfiguration.class })这里的 PersistenceConfig 是我自己的类。

有没有办法找出为什么 Controller 类没有被 MVC 添加到 URL 映射？

我不能分享代码，因为它不是公开的。感谢您对此进行调查。

Answer 1

Is there a way to find out why the Controller classes are not being added to URL mapping by the MVC?

总是很难找出为什么某些事情没有发生(除非它阻止启动)，但 Tomcat 中有一个配置项可能会派上用场来调试这个问题:

设置logEffectiveWebXml="true" on your context并在您的日志中查看有效的 web.xml - 从那里您应该能够确定 URL 处理是否有线，或者可能重载或以其他方式被抢占。