转自：http://blog.51cto.com/alinazh/1276363

在启动tomcat的时候出现错误：

Line: 220 - com/opensymphony/xwork2/spring/SpringObjectFactory.java:220:-1 .

严重: Exception starting filter struts2

Class: com.opensymphony.xwork2.spring.SpringObjectFactory

File: SpringObjectFactory.java

Method: getClassInstance

Line: 220 - com/opensymphony/xwork2/spring/SpringObjectFactory.java:220:-1

at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:437)

at org.apache.struts2.dispatcher.FilterDispatcher.init(FilterDispatcher.java:195)

at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:275)

at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:397)

at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:108)

at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:3709)

at org.apache.catalina.core.StandardContext.start(StandardContext.java:4356)

at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)

at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)

at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)

at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:626)

at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:553)

at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:488)

at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1215)

at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:293)

at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)

at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)

at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)

at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)

at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)

at java.lang.Thread.run(Unknown Source)

Caused by: java.lang.NullPointerException

at com.opensymphony.xwork2.spring.SpringObjectFactory.getClassInstance(SpringObjectFactory.java:220)

at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.verifyResultType(XmlConfigurationProvider.java:530)

at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addResultTypes(XmlConfigurationProvider.java:501)

at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:457)

at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages(XmlConfigurationProvider.java:275)

at org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages(StrutsXmlConfigurationProvider.java:111)

at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:204)

at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:66)

at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:380)

at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:424)

... 20 more

原因及解决办法：

不要引入包:struts2-spring-plugin-2.2.3.jar.

就是这么简单。

需要注意的是，这里指的不要引入，是在web工程的WEBROOT/WEB-INF/lib中也不要有多余的包，之前我的问题是lib中的包有冲突，

只在工程的buildpath中不引入，这个是不能控制包的冲突的！！

类似的问题及解决

启动服务器时出现异常：

警告: Failed startup of context }

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

<listener>

<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>

</listener>