这是登录的action 请问为什么登录失败不跳error界面？？？

/*
 * Generated by MyEclipse Struts
 * Template path: templates/java/JavaClass.vtl
 */
package com.hello.view.action;import java.util.Iterator;
import java.util.List;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import com.hello.data.bean.User;
import com.hello.model.service.IUserService;
import com.hello.view.form.LoginForm;/** 
 * MyEclipse Struts
 * Creation date: 09-07-2011
 * 
 * XDoclet definition:
 * @struts.action path="/login" name="loginForm" input="/login.jsp" scope="request" validate="true"
 * @struts.action-forward name="success1" path="/ok.jsp"
 * @struts.action-forward name="success" path="/adminok.jsp"
 */
public class LoginAction extends Action {
private IUserService userService;


public IUserService getUserService() {
return userService;
} public void setUserService(IUserService userService) {
this.userService = userService;
}
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) {
LoginForm loginForm = (LoginForm) form;
HttpSession session = request.getSession();
String username = loginForm.getUsername();
String passwd = loginForm.getPasswd();

User user = userService.isValidUser(username, passwd);
Integer flag = user.getFlag();
List list=userService.findByUsername(username);
String Username="";
String Passwd="";
String Companyname="";
Integer Flag=null;
Integer Count=null;
String Serverip="";
for( Iterator i = list.iterator() ; i.hasNext();)
  {
  User  user1= (User)i.next();
  Username=user1.getUsername();
  Passwd=user1.getPasswd();
  Companyname=user1.getCompanyname();
  Flag=user1.getFlag();
  Count=user1.getCount();
  Serverip=user1.getServerip();
  }

session.setAttribute("NAME",Username);
session.setAttribute("PASSWD", Passwd);
session.setAttribute("COMPANYNAME", Companyname);
session.setAttribute("FLAG", Flag);
session.setAttribute("SERVERIP", Serverip);
session.setAttribute("COUNT",Count);

if(flag.intValue()==1){

return mapping.findForward("flag1"); 
}
else if(flag.intValue()==2)
{

    return mapping.findForward("flag2"); 
}
else if(flag.intValue()==3)
{

return mapping.findForward("flag3"); 
}

request.setAttribute("error", "用户登录失败！");
return mapping.findForward("error");
}

}