求教 ClassCastException错误？
javax.servlet.ServletException: java.lang.Integer 
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:535) 
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:433) 
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) 
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) 
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:690) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:803) 


root cause 

java.lang.ClassCastException: java.lang.Integer 
com.yourcompany.struts.action.VehicleinfoAction.check_out(VehicleinfoAction.java:328) 
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) 
java.lang.reflect.Method.invoke(Method.java:585) 
org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:270) 
org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:187) 
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) 
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) 
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) 
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:690) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:803) 

我添加数据的时候总报上面的错误是怎么回事？怎样解决呀？ 

这是我的源代码： 
String cardid=vehicleinfoForm.getCardid(); 
String endtime=request.getParameter("endtime"); 
String starttime=request.getParameter("starttime"); 

HttpSession session=request.getSession(); 
String mon=(String) session.getAttribute("money"); 

float money=Float.valueOf(mon).floatValue(); 


VehicleDAO dao=new VehicleDAO(); 
int r=dao.add_rate(cardid, endtime, starttime, money); 
if(r>0) 
{ 
request.setAttribute("ms", "结算成功!"); 
return mapping.findForward("information"); 
}else 
{ 
request.setAttribute("ms", "系统出现异常！"); 
return mapping.findForward("information"); 
}

------解决方案--------------------
VehicleinfoAction.java:328这行类型转换出问题了
------解决方案--------------------
你哪一行报错，
或者这么说VehicleinfoAction.java:328行是你贴出来的代码中的哪句，
你只要看看那句代码是把什么类型转成什么类型就知道什么错了