@RequestMapping("/list_n{page:\\d+}")
 public String list(
     @PathVariable("page") Integer page,
     @RequestParam(value = "roleCode", required = false) String roleCode,
     @RequestParam(value = "roleName", required = false) String roleName,
     Model model) {
   Role role = new Role();
   role.setPageSize(20);
   role.setPage(page);
   role.setRoleCode(roleCode);
   role.setRoleName(roleName);
   Paging<Role> roles = roleService.findByRole(role);
   model.addAttribute("result", roles);
   model.addAttribute("s", role);
   return "admin/role/list";
 }