response 400 error

관련글 : exhibitlove.tistory.com/112

@RequestMapping(value = "/qlty/consumerInfo/putSftridn", method = RequestMethod.PUT)
public @ResponseBody ModelAndView putSftridn(@RequestBody Map<String,Object> params) throws Exception {
	ModelAndView mv = new ModelAndView("jsonView");
	try {
		int count = coltWaterInfosService.putSftridn(params);
		mv.addObject("count", count);
	} catch (Exception e) {
		e.printStackTrace();
	}
	return mv;
}

const putSftridnOfConsumer = function(dataRow) {
		var param = JSON.stringify(dataRow);
		$.ajax({
			url : '/qlty/consumerInfo/putSftridn' ,
			type : "PUT",
			datatype : "JSON",
			data : param,
			contentType: 'application/json;charset=UTF-8',
			success : function(result) {
				if (result.count > 0)
					console.log(`${dataRow.DMNO} 수정됨`);
			}
			,error : function(request, error) {
				console.log("message: " + request.responseText + ", error:" + error);
			}
		});
};

위의 api호출하는데 var param = JSON.stringify(dataRow); 요 코딩이 없으면 400에러 발생