项目突然报错，启动失败
Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:163)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:577)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:303)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301)
	at com.derbysoft.waterfall.pusher.application.PusherApplication.main(XXXApplication.java:51)
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:142)
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:104)
	at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:478)
	at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:211)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:182)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:160)
	... 8 more
Caused by: java.lang.IllegalStateException: StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[/prj_name-module_name] failed to start
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.rethrowDeferredStartupExceptions(TomcatWebServer.java:187)
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:126)
	... 13 more

Process finished with exit code 0

通过打断点发现TomcatService的host的state是SOPPED状态，所以抛出了[failed to start]这个异常，但是为什么是SOPPED状态的原因并没有发现

解决方案：不用Springboot内嵌的Tomcat，使用本地Tomcat启动

发现堆栈信息与之前有些不一样，多了具体的异常报错

Caused by: java.lang.IllegalArgumentException: The servlets named [A_Servlet] and [B_Servlet] are both mapped to the url-pattern [/status.ci] which is not permitted

两个类继承了同一个Servlet，改掉之后启动正常