Line: 209 - com/opensymphony/xwork2/spring/SpringO

启动服务器时出现异常：

警告: Failed startup of context com.google.apphosting.utils.jetty.DevAppEngineWebAppContext@1242b11{/,E:/workspace/uploadPhoto/war}

Class: com.opensymphony.xwork2.spring.SpringObjectFactory
File: SpringObjectFactory.java
Method: getClassInstance
Line: 209 - com/opensymphony/xwork2/spring/SpringObjectFactory.java:209:-1
Caused by: java.lang.NullPointerException  at com.opensymphony.xwork2.spring.SpringObjectFactory.getClassInstance(SpringObjectFactory.java:209)

原因两个：
1.lib中多导入包的大原因：去掉struts2-spring-plugin-2.1.8包即可，因为没有用到spring。
2.还有的原因是用spring了，却没加监听器，在web.xml里面加上

 <context-param>
  <param-name>contextConfigLocation</param-name>
  <param-value>classpath:applicationContext*.xml</param-value>
 </context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

转自：http://hi.baidu.com/zjameschen/blog/item/fd038b203e7ef5439922ed22.html