public static HttpResponse doPostOfQRCode(String url, String outStr)  {
    log.info("发送请求");
    DefaultHttpClient client = new DefaultHttpClient();
    HttpPost httpost = new HttpPost(url);
    httpost.setEntity(new StringEntity(outStr, "UTF-8"));//使用setEntity方法，将我们传进来的参数放入请求中
    int maxRetries = 3;
    for (int i = 0; i < maxRetries; i++) {
        try {
            long start = System.currentTimeMillis();
            HttpResponse response = client.execute(httpost);
            log.info("请求耗时：{}ms", System.currentTimeMillis() - start);
            log.info("请求数据："+ "返回："+JSONObject.toJSONString(response));
            return response;
        }catch (SocketTimeoutException e){
            if (i<maxRetries-1){
                log.info("第"+(i+1)+"次");
                try {
                    Thread.sleep(1000 * (i + 1));
                } catch (InterruptedException ex) {
                    throw new RuntimeException(ex);
                }
            }else{
                log.error("请求超时：{}", e.getMessage());
            }
        }catch (IOException e){
            log.error("网络异常：{}", e.getMessage());
        }
    }
    return null;
}