jQuery接受后台传递的List

@RequestMapping(params = "getUser")
@ResponseBody
public List<User>  getUser(){
List<User> list = new ArrayList<>();

return list;
}

$.ajax({
type: "POST",
url: "${pageContext.request.contextPath}/sys/user?getUser",
success: function(data){
jQuery.each(data, function (i, item) {
alert(item.id);
});
}
});