河南大学老校区邮编:用myeclipse是有严重：Invalid path /UserAction was requested

就是在输入http://loaclhost:8080/123/UserAction.do?method=list运行时出现这个错误（其中123为工程名）
路径为com.yourcompany.struts.action.UserAction，源代码：
package com.yourcompany.struts.action;
import。。。;
import com.yourcompany.struts.form.StuForm;
public class UserAction extends DispatchAction {

//取得学生列表，并发送到stu_list.jsp
public ActionForward list(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
List list = userDAO.getAlluser();
List temp = new ArrayList(list.size());
for (int i = 0; i < list.size(); i++) {
user user_po = (user) list.get(i);
StuForm user_vo=(StuForm)form;;
BeanUtils.copyProperties(user_vo, user_po);
temp.add(user_vo);
}
request.setAttribute("list", temp);
return mapping.findForward("stu_list");
}

public ActionForward execute(
ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response) throws IllegalAccessException, InvocationTargetException {
List list = userDAO.getAlluser();
List temp = new ArrayList(list.size());
for (int i = 0; i < list.size(); i++) {
user user_po = (user) list.get(i);
StuForm user_vo=(StuForm)form;
BeanUtils.copyProperties(user_vo, user_po);
temp.add(user_vo);
}
request.setAttribute("list", temp);
return mapping.findForward("stu_list");
}

}

你进行什么操作时候出现的这个错误啊，不说清楚

说清楚点嘛！！