Android connect to tethering socket

By testing it turns out the connection cannot be established on the tethering device.

But if we reverse the process and open a serversocket on the connected client. And connect to it from the tethering device, it will work.

So reversing the communication is the answer.

Server Side

class ServerThread implements Runnable {    public void run() {        socket = new Socket();        try {            serverSocket = new ServerSocket(SERVERPORT);        } catch (IOException e) {            e.printStackTrace();        }        while (!Thread.currentThread().isInterrupted()) {            try {                    socket = serverSocket.accept();                CommunicationThread commThread = new CommunicationThread(socket);                new Thread(commThread).start();            } catch (IOException e) {                e.printStackTrace();            }        }    }}

Client Side

class ClientThread implements Runnable {    @Override    public void run() {        try {            socket = new Socket();            InetSocketAddress socketAddress = new InetSocketAddress(SERVER_IP, SERVERPORT);            socket.connect(socketAddress);            CommunicationThread commThread = new CommunicationThread(socket);            new Thread(commThread).start();        } catch (UnknownHostException e1) {            e1.printStackTrace();        } catch (IOException e1) {            e1.printStackTrace();        }    }}

In a tethered wifi connection, connection provider can not work as a client. So we need to implement a bidirectional tcp socket connection. Use a server socket with a port number in device which is in tethering mode. This device act as a server. In client device use socket to access the client port with IP address.