Caused by: Cannot locate the chosen ObjectFactory implementation: spring - [unknown location]

今天在做struts和Spring架構整合的時候當我把項目部署到tomcat伺服器上之後控制台報了一個錯誤：

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:429)
 at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:471)
 ... 19 more

Caused by: Cannot locate the chosen ObjectFactory implementation: spring - [unknown location]

   at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:391)
 at org.apache.struts2.config.BeanSelectionProvider.alias(BeanSelectionProvider.java:362)
 at org.apache.struts2.config.BeanSelectionProvider.register(BeanSelectionProvider.java:288)
 at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:215)
 at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
 ... 21 more

當然，問題的解決是在第二個提示資訊：

Caused by: Cannot locate the chosen ObjectFactory implementation: spring - [unknown location]

出現問題的原因是：

       缺少struts2-spring-plugin-2.1.8.1.jar，該檔案是Spring與struts整合時必須要用到的一個jar檔案。匯入lib檔案夾下問題解決了。