定义如下 工具类 发送DELETE请求

    public static String deletePassword(String token, String lockNo, String phone){
        NutMap head = new NutMap();
        head.addv("Authorization", token);
        head.addv("Content-Type", "application/json");
        NutMap parm = new NutMap();
        parm.addv("deviceNum", lockNo);
        parm.addv("identifications", Arrays.asList(phone));
        String parmStr =  Json.toJson(parm);
        Response resp = Http.httpReq("https://paas.locksuiyi.com/deviceManagement/api/temporaryPassword.do",
                Request.METHOD.DELETE,
                parmStr,
                Header.create(head),
                50000,
                Sender.Default_Conn_Timeout);
        if(!resp.isOK()){
            log.error("设置删除密码失败 锁编号:" + lockNo + " 用户:" + phone + "  " + resp.getContent());
        }
        return resp.getContent();
    }

 String token="eyJhbGciOiJIUzI1NiJ9.eyJqdGkiOiIxIiwiaWF0IjoxNTY2Mjg3MTAwLCJhZG1pbklkIjoxMTgsImV4cCI6MTU2ODg3OTEwMH0._fWi_IZytnQw09_OMBhzoqLJT9DbWNjzpgUSAn3LdZ4";
        String deviceNum ="181201020000124";
        String identifications = "17600261502";
 String re = LockUtils.deletePassword(token,deviceNum,identifications);

请求 失败 返回 400
自定义 请求 DELETE却能成功

    public static String sendDeleteReq(String url,String token, String param) {
        PrintWriter out = null;
        BufferedReader in = null;
        StringBuilder result = new StringBuilder();
        try {
            log.info("sendPostJson - {}", url);
            //HTTP URL类 用这个类来创建连接
            URL httpUrl = new URL(url);
            //建立连接
            HttpURLConnection conn = (HttpURLConnection) httpUrl.openConnection();
            conn.setRequestMethod("DELETE");
            conn.setRequestProperty("Content-Type", "application/json");
            conn.setRequestProperty("connection", "keep-alive");
            conn.setRequestProperty("Authorization", token);
            //设置不要缓存
            conn.setUseCaches(false);
            conn.setInstanceFollowRedirects(true);
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.connect();
            out = new PrintWriter(conn.getOutputStream());
            out.print(param);
            out.flush();
            in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8"));
            String line;
            while ((line = in.readLine()) != null) {
                result.append(line);
            }
            log.info("recv - {}", result);
        } catch (ConnectException e) {
            log.error("调用HttpUtils.sendPost ConnectException, url=" + url + ",param=" + param, e);
        } catch (SocketTimeoutException e) {
            log.error("调用HttpUtils.sendPost SocketTimeoutException, url=" + url + ",param=" + param, e);
        } catch (IOException e) {
            log.error("调用HttpUtils.sendPost IOException, url=" + url + ",param=" + param, e);
        } catch (Exception e) {
            log.error("调用HttpsUtil.sendPost Exception, url=" + url + ",param=" + param, e);
        } finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                log.error("调用in.close Exception, url=" + url + ",param=" + param, ex);
            }
        }
        return result.toString();
    }