Jquery 子对象的Jqgrid表示

我有一个控制器方法如下

@RequestMapping(value = "/saveUser", method = RequestMethod.POST)
@ResponseBody
 public UserList saveUser(@RequestBody UserList userList) {
 //some operation
}

对象的结构如下所示

  public class UserList {
  private List<User> userList;
  //getters and setters

 }
  Public class User{
   private Integer id;
   private String name;
   private Role role;
  // getters and setters
   }

  Public class Role{
     private Integer id;
     private String name;
     private String description;
    //getters and setters
  }

我如何定义jqgrid，使submit能够命中上述控制器，即我们需要获得上述形式的json。请提及“colModel”， 当我使用像{name:'role.description'，index:'role.description'，width:55}这样的点运算符时，在用户对象中给出role的空对象

   {"userList":[{"id":"1","name":"xyz",  
    role:{"id":"1","name":"admin","description":"administrator"}}]}