package?UserBean; import?javax.servlet.http.HttpServletRequest; import?javax.servlet.http.HttpServletResponse; 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?Dao.UserDao; public?class?AddUserAction?extends?Action?{ @Override public?ActionForward?execute(ActionMapping?mapping,?ActionForm?form,?HttpServletRequest?request, HttpServletResponse?response)?throws?Exception?{ //?TODO?Auto-generated?method?stub user?u=(user)form; UserDao?ud=new?UserDao(); ud.addUser(u); return?mapping.findForward("list"); } }user u=(user)form;怎么解決Cannot cast from ActionForm to user？求指點