/**

     * 发送post请求

     * @param URL 数据发送地址

     * @param json json格式数据内容

     * @param headParams 请求头内容

     * @return 请求结果

     */

    public static String sendPost(String URL, Object json, HashMap<String,String> headParams) throws IOException {

        String result = "";

        CloseableHttpClient client = HttpClients.createDefault();

        try {

            HttpPost post = new HttpPost(URL);

            post.setHeader("Content-Type", "application/json");

            //增加请求头参数

            headParams.forEach((key,value) -> {

                post.addHeader(key, value);

            });

            StringEntity s = new StringEntity(json.toString(), "utf-8");

            s.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));

            post.setEntity(s);

            //构建超时等配置信息

            RequestConfig config = RequestConfig.custom().setConnectTimeout(60*1000) //连接超时时间

                    .setConnectionRequestTimeout(60*1000) //从连接池中取的连接的最长时间

                    .setSocketTimeout(60 * 1000) //数据传输的超时时间

                    .build();

            post.setConfig(config);

            CloseableHttpResponse response = client.execute(post);

            try {

                HttpEntity resEntity = response.getEntity();

                //回复接收

                result = EntityUtils.toString(resEntity, "UTF-8");

            } finally {

                response.close();

            }

        } catch (Exception e) {

            throw e;

        }finally {

            client.close();

        }

        return result;

    }