Unable to load configuration. - [unknown location]

问题描述：
严重: Dispatcher initialization failed
Unable to load configuration. - [unknown location]
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:70)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:446)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:490)
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.<init>(ApplicationFilterConfig.java:105)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4958)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5652)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1571)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1561)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: Cannot locate the chosen ObjectFactory implementation: spring - [unknown location]
at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:441)
at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:412)
at org.apache.struts2.config.BeanSelectionProvider.register(BeanSelectionProvider.java:327)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:226)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
... 16 more

一月 23, 2018 10:25:39 上午 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:502)
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.<init>(ApplicationFilterConfig.java:105)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4958)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5652)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1571)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1561)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: Unable to load configuration. - [unknown location]
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:70)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:446)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:490)
... 14 more
Caused by: Cannot locate the chosen ObjectFactory implementation: spring - [unknown location]
at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:441)
at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:412)
at org.apache.struts2.config.BeanSelectionProvider.register(BeanSelectionProvider.java:327)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:226)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
... 16 more
解决方法：在struts中找到struts2-spring-plugin-2.3.15.jar包并引用。与struts.xml中的如下配置有关系，
<!-- 设置struts的对象工厂,由spring进行创建 (更换Struts2的工厂)-->
<!-- 实际上这个常量不配置也可以,如果项目中使用了struts2-spring-plugin-2.3.15.jar那么可以不用配置。  如果使用了其他的第三方plugin,建议明确配置struts2的对象工厂 -->
    <constant name="struts.objectFactory" value="spring" />