使用jquery将json数据传递给spring控制器的错误请求

Question

我将JSON传递给Spring控制器时得到Status Code:400 Bad Request。

JSP中的脚本：

var retailerId = $("#retailerId").val();
var retailerStatus = $("#retailerStatus").val();
var firstName = $("#firstName").val();
var lastName = $("#lastName").val();
var drvLicense = $("#drvLicense").val();
var ssn = $("#ssn").val();
var dob = $("#dob").val();

var json = {
    "retailerId" : retailerId,
    "retailerStatus" : retailerStatus,
    "firstName" : firstName,
    "lastname" : lastName,
    "drvLicense" : drvLicense,
    "ssn" : ssn,
    "dob" : $.datepicker.formatDate('yy-mm-dd', dob)
};

$("#spinner").show();

$.ajax({
    url : "adminsearchOwner/searchOwners",
    type : "POST",
    dataType : 'json',
    contentType : 'application/json',
    data : json = JSON.stringify(json),
    success : function(data) {
        alert(111);
    },
    error : function() {
        $("#spinner").hide();
    }
});

控制器

@Controller
public class AdminSearchOwnersController {

    private static final Logger LOGGER = Logger.getLogger(AdminSearchOwnersController.class);

    /**
     * 
     * @param webDataBinder
     */
    @ModelAttribute("ownerSearchDTO")
    public OwnerSearchDTO getOwneSearchDTOr() {
        return new OwnerSearchDTO();
    }

    @RequestMapping(value = "/auth/adminsearchOwner", method = RequestMethod.GET)
    public ModelAndView showSearchOwnerForm() {
        ModelAndView modelAndView = new ModelAndView();
        modelAndView.setViewName("auth/managelicense/searchOwnerForm");
        return modelAndView;
    }

    @RequestMapping(value = "/auth/adminsearchOwner/searchOwners", method = RequestMethod.POST)
    public @ResponseBody
    String searchOwner(@RequestBody OwnerSearchDTO ownerSearchDTO, HttpSession session) {
        Collection<OwnerSearchDTO> list = new ArrayList<OwnerSearchDTO>();
        return "";
    }
}

但是控件不会转到控制器类的searchOwner()方法。谁能帮我这个？我在过去的3天里一直在努力。