求助！！struts2 配置问题

Question

启动后报如下错：
严重: createMBeans: Throwable
java.lang.NullPointerException
at org.apache.catalina.mbeans.MBeanUtils.createObjectName(MBeanUtils.java:1086)
at org.apache.catalina.mbeans.MBeanUtils.createMBean(MBeanUtils.java:504)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:570)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:366)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:535)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:498)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:656)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:628)
at org.apache.catalina.mbeans.ServerLifecycleListener.createMBeans(ServerLifecycleListener.java:278)
at org.apache.catalina.mbeans.ServerLifecycleListener.lifecycleEvent(ServerLifecycleListener.java:129)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:747)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
2012-9-5 9:57:20 org.apache.catalina.core.StandardService start
信息: Starting service Catalina
2012-9-5 9:57:20 org.apache.catalina.core.StandardEngine start
信息: Starting Servlet Engine: Apache Tomcat/6.0.35
2012-9-5 9:57:20 org.apache.catalina.startup.Catalina start
严重: Catalina.start: 
LifecycleException:  Error initializaing :  java.lang.NullPointerException
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4451)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
2012-9-5 9:57:20 org.apache.catalina.startup.Catalina start
信息: Server startup in 201 ms

Answer 1

改了几个地方
又报这个错：
严重: Exception starting filter struts2
java.lang.NoClassDefFoundError: org/apache/commons/lang3/StringUtils
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.register(XmlConfigurationProvider.java:209)
at org.apache.struts2.config.StrutsXmlConfigurationProvider.register(StrutsXmlConfigurationProvider.java:102)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:210)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:66)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:390)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:437)
at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:51)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:295)
at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:422)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:115)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4072)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4726)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang3.StringUtils
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
... 26 more
2012-9-5 10:24:04 org.apache.catalina.core.StandardContext start
严重: Error filterStart
2012-9-5 10:24:04 org.apache.catalina.core.StandardContext start
严重: Context [/struts2] startup failed due to previous errors
2012-9-5 10:24:04 org.apache.catalina.startup.HostConfig deployDescriptor

Answer 2

看一下这篇文章吧  希望对你有用http://blog.csdn.net/jeffyu328/article/details/7721022

Answer 3

commons-lang-2.1.jar这个jar包没有导入，或者重复。

Answer 4

这个是运行是路径的问题，你看看这篇文章，很详细，希望对你有用：
http://blog.sina.com.cn/s/blog_5163b2980100bocf.html

Answer 5

这个是运行时路径的问题，你看看这篇文章，很详细，希望对你有用：
http://blog.sina.com.cn/s/blog_5163b2980100bocf.html