There is no result type defined for type 'json' mapped with name 'success'. Did you mean 'json'?

错误信息：

严重: Exception starting filter struts2
Unable to load configuration. - action - file:/C:/Users/Xiejdm/Workspaces/MyEclipse%20Professional%202014/.metadata/.me_tcat7/webapps/0719StrutsCRUD/WEB-INF/classes/struts.xml:24:86
    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:277)
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
    at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:382)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:103)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4650)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5306)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    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:744)
Caused by: Error building results for action userinfo in namespace /UserEntity - action - file:/C:/Users/Xiejdm/Workspaces/MyEclipse%20Professional%202014/.metadata/.me_tcat7/webapps/0719StrutsCRUD/WEB-INF/classes/struts.xml:24:86
    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)
    ... 21 more
Caused by: There is no result type defined for type 'json' mapped with name 'success'.  Did you mean 'json'? - result - file:/C:/Users/Xiejdm/Workspaces/MyEclipse%20Professional%202014/.metadata/.me_tcat7/webapps/0719StrutsCRUD/WEB-INF/classes/struts.xml:25:24
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.buildResults(XmlConfigurationProvider.java:613)
    at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addAction(XmlConfigurationProvider.java:364)
    ... 26 more

解决方案：我的情况是缺少struts2-json-plugin-2.3.16.3.jar包。还有要注意的地方是extends="json-default,hibernate-default"，而不是extends="struts-default".