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org.apache.catalina.core.ContainerBase addChildInternal
SEVERE: ContainerBase.addChild: start:
org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/CollegeWebsite]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:895)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:871)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:962)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1603)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:469)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:332)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:597)
at java.lang.Thread.run(Thread.java:637)
Caused by: java.lang.UnsupportedClassVersionError: com/Servlets/AddCourse : Unsupported major.minor version 51.0 (unable to load class com.Servlets.AddCourse)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2893)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1170)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1556)
at org.apache.catalina.startup.WebAnnotationSet.loadClass(WebAnnotationSet.java:480)
at org.apache.catalina.startup.WebAnnotationSet.loadApplicationServletAnnotations(WebAnnotationSet.java:130)
at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:66)
at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:381)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:858)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:345)
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:5161)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 11 moreHow can I overcome this error? My project was deployed on Eclipse easily but it can't deploy when I deploy it directly through Tomcat server.
You have a version conflict, please verify whether compiled version and JVM of Tomcat version are same. you can do it by examining tomcat startup .bat , looking for JAVA_HOME
This error happens because of your Jre version of Eclipse and Tomcat are mismatched ..either change eclipse one to tomcat one or ViceVersa..
Both should be same ..Java version mismatched ..Check it
来源：https://stackoverflow.com/questions/14750747/org-apache-catalina-lifecycleexception-failed-to-start-component-standardengin