Question

我有以下代码来检查服务器可用性，但它不起作用我使用连接管理器检查互联网可用性它运作良好

public static boolean isConnected(Context context, String url){
    ConnectivityManager connectivityManager=(ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
    if(connectivityManager!=null){

         if ((connectivityManager.getNetworkInfo(0).getState() == NetworkInfo.State.CONNECTED)
                    ||(connectivityManager.getNetworkInfo(0).getState() == NetworkInfo.State.CONNECTING)
                    ||(connectivityManager.getNetworkInfo(1).getState() == NetworkInfo.State.CONNECTING)
                    ||(connectivityManager.getNetworkInfo(1).getState() == NetworkInfo.State.CONNECTED))
            {


                    try{
                        URL myUrl = new URL(url);
                        URLConnection connection = myUrl.openConnection();
                        connection.setConnectTimeout(5000);
                        connection.connect();
                        return true;
                    } catch (Exception e) {
                        // Handle your exceptions
                        return false;
                    }



            }

    }
    return false;

}

Answer 1

有很多方法。但我选择这种方式。你可以像下面这样实施：

HttpClient httpclient = new DefaultHttpClient();
    String response = null;
    URI url;
    try {

        String s = "url";

        url = new URI(s.replace(" ", "%20"));

        Log.e("my webservice", "My webservice : " + url);

        HttpGet httpget = new HttpGet(url);
        HttpResponse httpResponse = null;

        HttpParams httpParameters = new BasicHttpParams();
        // Set the timeout in milliseconds until a connection is
        // established.
        // The default value is zero, that means the timeout is not used.
        int timeoutConnection = 3000;
        HttpConnectionParams.setConnectionTimeout(httpParameters,
                timeoutConnection);
        // Set the default socket timeout (SO_TIMEOUT)
        // in milliseconds which is the timeout for waiting for data.
        int timeoutSocket = 5000;
        HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);


        DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);

        // Execute HTTP Post Request
        httpResponse = httpClient.execute(httpget);

        response = EntityUtils.toString(httpResponse.getEntity(), "UTF-8");
            Log.e("Login service", "resonse length : " + url);


            if(response.length()>0){
                return true;//server available
            }else{
                return false;//server not available
            }

            // this is what we extended for the getting the response string
            // which we going to parese for out use in database //


    } catch (Exception e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    return false;

Answer 2

你可以这样做：

         HttpParams httpParams = new BasicHttpParams();
        //int some_reasonable_timeout = (int) (30 * DateUtils.SECOND_IN_MILLIS);
        int some_reasonable_timeout = 10;
        HttpConnectionParams.setConnectionTimeout(httpParams, some_reasonable_timeout);
        HttpConnectionParams.setSoTimeout(httpParams, some_reasonable_timeout);
        //DefaultHttpClient client = new DefaultHttpClient();

        // get the response
        HttpResponse response = null;
        try {
            response = client.execute(request);
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        StatusLine status = response.getStatusLine();
        Log.d("tag","status is"+status.toString());
          if (status.getStatusCode() == HttpStatus.SC_OK)
          {
             //cserver is available
          }
          else
          {
              //server is not available
          }

Answer 3

您可以简单地声明Socket。我在我的许多项目中使用以下代码，超时肯定有效。

Socket socket;
final String host = "your.server.IP.or.host";
final int port = 80;
final int timeout = 30000;   // 30 seconds

try {
  socket = new Socket();
  socket.connect(new InetSocketAddress(host, port), timeout);
}
catch (UnknownHostException uhe) {
  Log.e("ServerSock", "I couldn't resolve the host you've provided!");
}
catch (SocketTimeoutException ste) {
  Log.e("ServerSock", "After a reasonable amount of time, I'm not able to connect, Server is probably down!");
}
catch (IOException ioe) {
  Log.e("ServerSock", "Hmmm... Sudden disconnection, probably you should start again!");
}

但是，这可能很棘手。正好在UnknownHostException s，可能需要更长时间才能超时，大约45秒 - 但另一方面，这通常发生在你无法解析主机时，这更像是意味着你的互联网访问错误配置了DNS解析（这是不可能的）。

无论如何，如果你想对冲你的赌注，你可以简单地使用你的IP地址而不是主机。这样，如果您的任何例外情况发生，您将确保这不是问题。

如何检查android中的服务器可用性

3 个答案: