httpurlconnection get String

public static String getJSON(String url, int timeout) {
    HttpURLConnection c = null;
    try {
        long requestStart = System.currentTimeMillis();
        URL u = new URL(url);
        c = (HttpURLConnection) u.openConnection();
        c.setRequestMethod("GET");
        c.setRequestProperty("Content-length", "0");
        c.setUseCaches(false);
        c.setAllowUserInteraction(false);
        c.setConnectTimeout(timeout);
        c.setReadTimeout(timeout);
        c.connect();
        int status = c.getResponseCode();

        switch (status) {
            case 200:
            case 201:
                BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
                StringBuilder sb = new StringBuilder();
                String line;
                while ((line = br.readLine()) != null) {
                    sb.append(line+"\n");
                }
                br.close();
                return sb.toString();
        }
        long requestStop = System.currentTimeMillis();
        StatisticsUtil.networkEvent(SysConstant.CONVERT_TOKEN_HOST,
                status,
                requestStart, requestStop,
                StatisticsUtil.calRequestSize(url, mapHeaders),
                StatisticsUtil.calResponseSize(httpResponse, result),
                statusCode, serverMessage);

    } catch (MalformedURLException ex) {
    } catch (IOException ex) {
    } finally {
        if (c != null) {
            try {
                c.disconnect();

            } catch (Exception ex) {
            }
        }
    }
    return null;
}