org.springframework.web.SpringServletContainerInitializer cannot be cast to javax.servlet.Servle...

严重: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].StandardContext[]]
        at java.util.concurrent.FutureTask.report(FutureTask.java:122)
        at java.util.concurrent.FutureTask.get(FutureTask.java:188)
        at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1123)
        at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:800)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
        at java.util.concurrent.FutureTask.run(FutureTask.java:262)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].StandardContext[]]
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
        ... 6 more
Caused by: java.lang.ClassCastException: org.springframework.web.SpringServletContainerInitializer cannot be cast to javax.servlet.ServletContainerInitializer
        at org.apache.catalina.startup.ContextConfig.getServletContainerInitializer(ContextConfig.java:1670)
        at org.apache.catalina.startup.ContextConfig.getServletContainerInitializers(ContextConfig.java:1652)
        at org.apache.catalina.startup.ContextConfig.processServletContainerInitializers(ContextConfig.java:1562)
        at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1270)
        at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:878)
        at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:376)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5322)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
        ... 6 more

此类问题的多半是web.xml配置有问题，或者是pom.xml中的jar包冲突。
根据关键信息org.springframework.web.SpringServletContainerInitializer cannot be cast to javax.servlet.ServletContainerInitializer
得知基本是ServletContainerInitializer类版本不一致造成的。
经过排查，是由于我在pom.xml中引入的javaee jar包有问题

            javax
            javaee-api
            7.0
        

此处的javaee-api与tomcat的javaee-api冲突
所以可以采取删除这个jar包引用，或者加上关键字

            javax
            javaee-api
            provided
            7.0
        

这个关键字的设置是起到定义jar包生存周期的作用，这个设置认为在环境中已经存在这个jar包了就不再部署了。
所以这个关键字对于解决jar包冲突能起到很好的作用。

转载于:https://my.oschina.net/u/2250363/blog/666848