重写action类

public abstract class webAction extend Action(){
//重写基类的excute方法
final public ActionForward execute(ActionMapping actionMapping,
   ActionForm actionForm, HttpServletRequest request,
   HttpServletResponse response)throws Exception{
  if()//写上你要做的判断
    return actionMapping.findForward("fail");
  else
    return doexecute(actionMapping,actionForm,request,response);
}
//增加了一个抽象的方法,这样子类只要重写这个方法就可以了
abstract public ActionForward doexecute(ActionMapping actionMapping,
   ActionForm actionForm, HttpServletRequest request,
   HttpServletResponse response);

}