在一个Spring MVC项目里，启动项目报错：
SEVERE: 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$Sync.innerGet(FutureTask.java:252)
at java.util.concurrent.FutureTask.get(FutureTask.java:111)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1130)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:782)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1568)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1558)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
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:722)
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)
... 7 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:1543)
at org.apache.catalina.startup.ContextConfig.processServletContainerInitializers(ContextConfig.java:1464)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1190)
原因主要是 javax.servlet-api 将spring容器当成了servlet容器导致了类型转换错误。使用servlet-api 3.1.0可解决。
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
注意：scope需要为provided