public static String doPostStr(String httpUrl, String str) {

         HttpPost httpPost = null;

         try {

             HttpClient client = getHttpClient();

             httpPost = new HttpPost(httpUrl);

             StringEntity entity = new StringEntity(str);

             entity.setContentType("application/x-www-form-urlencoded");

             entity.setContentEncoding("utf-8");

             httpPost.setEntity(entity);

             HttpResponse response = client.execute(httpPost);

             String result = EntityUtils.toString(response.getEntity(), DEFAULT_CHARSET);

             return result;

         } catch (Exception e) {

             logger.error("http post is error," + e.getMessage(), e.fillInStackTrace());

         } finally {

             httpPost.releaseConnection();

         }

         return null;

     }