Caused by: Parent package is not defined: json-default - [unknown location]

Unable to load configuration. - [unknown location]
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:70)
at org.apache.struts2.dispatcher.Dispatcher.getContainer(Dispatcher.java:970)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:438)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:482)
at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:57)
at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:279)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:260)
at org.apache.catalina.core.ApplicationFilterConfig.(ApplicationFilterConfig.java:105)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4689)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5329)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1092)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1834) at java.util.concurrent.Executors$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: Parent package is not defined: json-default - [unknown location] at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.buildPackageContext(XmlConfigurationProvider.java:674) at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:523) at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages(XmlConfigurationProvider.java:295) at org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages(StrutsXmlConfigurationProvider.java:112) at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:264) at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67) … 21 more 九月 22, 2016 9:12:20 下午 org.apache.catalina.core.StandardContext filterStart 严重: Exception starting filter struts2 Unable to load configuration. - [unknown location] at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:496) at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74) at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:57) at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:279) at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:260) at org.apache.catalina.core.ApplicationFilterConfig.(ApplicationFilterConfig.java:105) at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4689) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5329) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:147) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1092) at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1834)
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: Unable to load configuration. - [unknown location]
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:70)
at org.apache.struts2.dispatcher.Dispatcher.getContainer(Dispatcher.java:970)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:438)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:482)
… 18 more
Caused by: Parent package is not defined: json-default - [unknown location]
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.buildPackageContext(XmlConfigurationProvider.java:674)
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:523)
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages(XmlConfigurationProvider.java:295)
at org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages(StrutsXmlConfigurationProvider.java:112)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:264)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
… 21 more

这个错误的原因是struts2在package的配置中继承了json-default
解决方法是：引入struts2-json-plugin-2.1.8.1.jar