Android Socket客户端未连接到服务器

Question

I'm trying to connect an android client to a pc server, but the client always crashes and doesn't connect to the server. the server is composed of two methods, one that wait for a client to connect and another that print the client connected (I didn't use thread, i only connect one client) Server (i will show only the first method):

public Socket listeningClient () 
{
    try 
    {
        server = new ServerSocket(8080);
        client = server.accept();
        server.close();
    }
    catch (Exception e)
    {
        System.out.println(e.getMessage());
        System.exit(1);
    }
    return client;
}

in the client there are a button that call the method to create the socket on click:

Client

public class Client {
  String IP = "192.168.1.4";
  int portaServer = 8080;
  Socket miosocket = null;

  public void connetti() {
    try {
        InetAddress nomeServer = InetAddress.getByName(IP);
        miosocket = new Socket(nomeServer, portaServer);
        miosocket.close();
    }
    catch (UnknownHostException e) {
        e.printStackTrace();
        Log.e("MyApp", "UnknownHost");
    }
    catch (Exception e) {
        e.printStackTrace();
        Log.e("MyApp", "Exception");
        System.exit(1);
    }
  }
}

The app always crash at the line: miosocket = new Socket(nomeServer, portaServer); and Throws the Exception(the second one). Can someone please tell me if is my code that is wrong(I'm pretty sure that the problem is the code) or there are problem on the server?

(in the AndroidManifest.xml I used these permission :

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>

)

Answer 1

Per the exception you quoted in your comments, you cannot perform blocking IO on the main thread. You need to spawn a thread (or use AsyncTask and do the work there.

If you are really trying to host a server on an Android service, you should do so by creating a Service and using that to host a thread that starts the server and processes requests.