java - 路由器没有输入时的HttpUrlConnection超时

Question

我正在使用HttpUrlConnection连接到服务器。问题是我通过wifi连接到路由器。因此，我在我的设备中看到了网络。但是路由器没有连接到任何互联网输入，并且连接进入无限循环。这是代码 private String getHttpResponse(final String srcUrl) {

    HttpURLConnection urlConnection = null;
    FileOutputStream fos = null;
    try {
        URL url = new URL(srcUrl);
        urlConnection = (HttpURLConnection) url.openConnection();
        urlConnection.setRequestMethod("GET");
        urlConnection.setConnectTimeout(TIMEOUT);
        urlConnection.setReadTimeout(TIMEOUT);
        urlConnection.setRequestProperty("Content-Type", "application/json");
        mETag = readETagFromPrefForCategory();

        urlConnection.setRequestProperty("If-None-Match", mETag);

        Log.v("abcd","####### before connection ######");

        urlConnection.connect();

        Log.v("abcd","####### after connection ######");
        mETag =  urlConnection.getHeaderField("ETag");

        if (urlConnection.getResponseCode() == HttpURLConnection.HTTP_NOT_MODIFIED) {
            Log.v("online","not modifed");
            return null;
        }

        if (urlConnection.getResponseCode() != HttpURLConnection.HTTP_OK) {
            Log.w(TAG, "Bad response [" + urlConnection.getResponseCode() + "] from (" + srcUrl + ")");
            return null;
        } 

        BufferedReader rd = new BufferedReader(new InputStreamReader(
                urlConnection.getInputStream()));

        fos = createJson();


        StringBuilder sb = new StringBuilder();

        String line = "";

        while ((line = rd.readLine()) != null) {
            sb.append(line);
            if(fos != null)fos.write(line.getBytes());
        }
        if(fos != null)writeETagForCategory(mETag);

        if (rd != null) {
            Log.v("online","buffered reader closed");
            rd.close();
        }

        return sb.toString();

    } catch (UnknownHostException e) {
        Log.e("Error: ", "Message - " + e.getMessage());
    } catch (MalformedURLException e) {
        Log.e("Error: ", "Message - " + e.getMessage());
    } catch (IOException e) {
        Log.e("Error: ", "Message - " + e.getMessage());
    } finally {
        if (fos != null) {
            try {
                fos.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
    return null;
}