Springboot RestTemplate-- 用更优雅的方

更多，参看：案例，下面代码是我根据案例编写的一个请求：

    public static String postObject(){
        RestTemplate restTemplate = new RestTemplate();
        String url = "http://222.222.222.222:222/dcmp/ws/manuInfo";
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON_UTF8);

        JSONObject rspObj = new JSONObject();
        rspObj.put("creditcode_nbr", "913100001331360409G");
        rspObj.put("dataupdate_nbr", "12345678");
        rspObj.put("warehousearea_nbr", "913100001331360409G.01");
        rspObj.put("start_date", "20200401");
        ArrayList<Map> inventoryInfo_list = new ArrayList<>();
        Map inventoryInfo_list_item = new HashMap();
        inventoryInfo_list_item.put("whpname_nbr","1049");
        inventoryInfo_list_item.put("number","2");
        inventoryInfo_list_item.put("unit","K");
        inventoryInfo_list.add(inventoryInfo_list_item);
        rspObj.put("inventoryInfo_list", inventoryInfo_list);

        HttpEntity<JSONObject> request = new HttpEntity<>(rspObj, headers);
        ResponseEntity<String> response = restTemplate.postForEntity( url, request , String.class );
        return response.getBody();
    }