严重: Exception starting filter struts2,Error:Action class [] not found

想手动搭建SSH2框架，编译的时候报如下错误（包是从利用myeclipse7.5搭建成功的LIB目录下COPY过来的）
错误如下：
严重: Exception starting filter struts2
Action class [SaveUserAction] not found - action - file:/E:/Workspaces/test/WebRoot/WEB-INF/classes/struts.xml:8:55
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.verifyAction(XmlConfigurationProvider.java:374)
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addAction(XmlConfigurationProvider.java:329)
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:429)
at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages(XmlConfigurationProvider.java:239)
at org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages(StrutsXmlConfigurationProvider.java:111)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reload(DefaultConfiguration.java:152)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:52)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:395)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:452)
at org.apache.struts2.dispatcher.FilterDispatcher.init(FilterDispatcher.java:201)
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:3800)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4450)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:722)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:516)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
at org.apache.catalina.startup.Catalina.start(Catalina.java:583)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)


struts.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC 
  "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" 
  "http://struts.apache.org/dtds/struts-2.0.dtd"> 
 
<struts>
  <package name="user" extends="struts-default">
  <action name="saveUser" class="SaveUserAction">
  <result name="success" >/success.jsp </result>
  <result name="input">/save.jsp </result>
  </action>
  </package>
</struts>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">


<filter>
  <filter-name>struts2 </filter-name>
  <filter-class>
  org.apache.struts2.dispatcher.FilterDispatcher
  </filter-class>
</filter>

<filter-mapping>
  <filter-name>struts2 </filter-name>
  <url-pattern>/* </url-pattern>
</filter-mapping>

<listener>
  <listener-class>
  org.springframework.web.context.ContextLoaderListener
  </listener-class>
</listener>
  <welcome-file-list>
  <welcome-file>index.jsp </welcome-file>