http post

    public static boolean sendPostRequest(String path, String data) throws Exception{
//        StringBuilder sb = new StringBuilder();
//        if (params != null && !params.isEmpty()) {
//            for (Map.Entry<String, String> entry : params.entrySet()) {
//                sb.append(entry.getKey()).append('=').append(URLEncoder.encode(entry.getValue(), enc)).append('&');
//            }
//            sb.deleteCharAt(sb.length() - 1);
//        }
        byte[] entitydata = data.getBytes();//得到实体的二进制数据
        URL url = new URL(path);
        HttpURLConnection conn = (HttpURLConnection)url.openConnection();
        conn.setRequestMethod("POST");
        conn.setConnectTimeout(5 * 1000);
        conn.setDoOutput(true);//如果通过post提交数据，必须设置允许对外输出数据
        conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        conn.setRequestProperty("Content-Length", String.valueOf(entitydata.length));
        OutputStream outStream = conn.getOutputStream();
        outStream.write(entitydata);
        outStream.flush();
        outStream.close();
        if(conn.getResponseCode()==200){
            return true;
        }
        return false;
    }