Struts 2.x Unable to load configuration.

问题分析：遇到该问题一般是struts中某个配置文件没有正确配置，比如：

1.class中的TestAction没有成功加载：

    <constant name="struts.i18n.reload" value="true" />
     <!-- <include file="struts/struts-test.xml"/> -->
     <package name="system" extends="struts-default">
        <action name="totalfilter" class="TestAction">  
            <result name="success" >success.jsp</result>           
        </action>  
    </package>

2.将name误写为type如：

<!-- 正确写法 -->
<result name="error">/error.jsp</result>
<!-- 错误写法 -->
<result type="error">/error.jsp</result>

出错代码：

严重: Exception starting filter struts2
Unable to load configuration. - action - file:/E:/Workspaces/MyEclipse 2014/struts2/apache-tomcat-7.0.5/webapps/Struts2_2000_StrutsTags/WEB-INF/classes/struts.xml:14:71
    at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:58)
    at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:360)
    at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:403)
    at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:69)
    at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:48)
    at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:273)
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:254)
    at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:372)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:98)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4405)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5037)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:140)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:812)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:787)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:570)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1010)
    at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:933)
    at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:468)
    at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1267)
    at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:308)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:89)
    at org.apache.catalina.util.LifecycleBase.setState(LifecycleBase.java:328)
    at org.apache.catalina.util.LifecycleBase.setState(LifecycleBase.java:308)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1043)
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:738)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:140)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1035)
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:289)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:140)
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:442)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:140)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:674)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:140)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:596)
    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:303)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:431)
Caused by: Error building results for action tags in namespace  - action - file:/E:/Workspaces/MyEclipse9/struts2/apache-tomcat-7.0.5/webapps/Struts2_2000_StrutsTags/WEB-INF/classes/struts.xml:14:71
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addAction(XmlConfigurationProvider.java:366)
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:460)
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages(XmlConfigurationProvider.java:265)
    at org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages(StrutsXmlConfigurationProvider.java:111)
    at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:189)
    at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:55)
    ... 40 more
Caused by: There is no result type defined for type 'tag' mapped with name 'success'.  Did you mean 'tag'? - result - file:/E:/Workspaces/MyEclipse9/struts2/apache-tomcat-7.0.5/webapps/Struts2_2000_StrutsTags/WEB-INF/classes/struts.xml:15:32
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.buildResults(XmlConfigurationProvider.java:613)
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addAction(XmlConfigurationProvider.java:364)
    ... 45 more
2011-10-24 11:36:09 org.apache.catalina.core.StandardContext startInternal
严重: Error filterStart