Tutorial für telnet

package project.robot.network;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

import project.robot.BluetoothConnection;
import android.os.AsyncTask;

public class TCPServer extends AsyncTask<Void, Integer, Void> {
    int port;               //Port on which server is running
    String clientIP;        //IP address of remote client
    ServerSocket serverSocket;  //Server Socket
    Socket clientSocket;    //Socket connected to client
    DataOutputStream out;   //Output stream object to send data
    DataInputStream in;         //Input Stream object to receive data

    boolean flag;
    boolean videoFlag;  //Used to toggle video
    private VideoThread vthread;    //Video Thread Object

    public static BluetoothConnection conn;

    /*
     * Starts a TCP Server which listens to incoming connections
     */
    public TCPServer(int port) {
        this.port = port;
        videoFlag = false;
        vthread = null;
    }

    @Override
    protected Void doInBackground(Void... arg0) {
        int msg;    

        //Initiating server socket
        try {
            serverSocket = new ServerSocket(port);
            flag = true;
        } catch (IOException e1) {
            //TODO Auto-generated catch block
            System.out.println("Tcpserver: unable to bind socket");
            e1.printStackTrace();
            flag = false;
        }

        System.out.println("TCPServer: Server started");

        while(flag) {
            try {
                //Accepting incoming connection
                clientSocket = serverSocket.accept();
                clientIP = clientSocket.getInetAddress().getHostAddress();
                System.out.println("TCPServer: Connected to client at " + clientIP);

                //Getting input and output streams
                in = new DataInputStream(clientSocket.getInputStream());
                out = new DataOutputStream(clientSocket.getOutputStream());
                msg = 1;

                //Start VideoThread
                try {
                    vthread = new VideoThread(clientIP);
                    vthread.startVideo();
                    System.out.println("TCPServer: Video started");
                    videoFlag = true;
                } catch (Exception e) {
                    e.printStackTrace();
                    vthread = null;
                    System.out.println("TCPServer: Error while starting video");
                }

                //Reading input commands and signaling processing function
                while(flag && msg != 0) {
                    msg = in.readInt();
                    publishProgress(msg);
                }

                //Stopping video streaming if running
                if(vthread != null) {
                    vthread.stopVideo();
                    vthread = null;
                }
                System.out.println("TCPServer: Video stopped");

                //Closing Connection to client
                clientSocket.close();
                clientSocket = null;
                System.out.println("TCPServer: Closed connection to host at " + clientIP);
                clientIP = "null";

            } catch (IOException e) {
                if(clientSocket != null) {
                    clientSocket = null;
                }
                flag = false;
                System.out.println("TCPServer: Error while accepting or closing client connection");
            }
        }

        //Closing serverSocket
        if(serverSocket != null) {
            try {
                serverSocket.close();
                System.out.println("TCPServer: Server Socket Closed");
            } catch (IOException e) {
                e.printStackTrace();
                System.out.println("TCPServer: Error while closing socket");
            }
            serverSocket = null;
        }

        System.out.println("TCPServer: Server stopped");
        return null;
    }

    private void sendSignal(int signal) {
        if(conn != null)
            conn.send(signal);
        else
            System.out.println("TCPServer: null conn, can't send value");
    }


    @Override
    protected void onProgressUpdate(Integer... integers) {
        //Method is called every time a publishProgress is called from doInBackground
        for(Integer integer : integers) {
            System.out.println("TCPServer: Message received - " + integer);
            switch(integer) {
            case 1:
                //Enable SMS service
                if(vthread != null)
                    vthread.msgFlag = true;
                break;
            case 2:
                //Move backward
                sendSignal(2);
                break;
            case 4:
                //Move left
                sendSignal(4);
                break;
            case 5:
                //Stop
                sendSignal(5);
                break;
            case 6:
                //Move right
                sendSignal(6);
                break;
            case 7:
                //Buzzer toggle
                sendSignal(7);
            case 8:
                //Move forward
                sendSignal(8);
                break;
            case 9:
                //Toggle Video
                toggleVideo();
                break;
            default:
                System.out.println("TCPServer: Unrecognized instruction : " + integers[0]);
                break;
            }
        }
    }

    /*
     * Toggles video streaming state
     * if it was on then it will stop it
     * else it will start video streaming
     */
    private void toggleVideo() {
        //If videoFlag is true then stop Video else start video
        if(vthread==null)
            return;

        if(vthread.videoStream) {
            vthread.videoStream = false;
            System.out.println("TCPServer: Video streamming stopped");
        } else {
            System.out.println("TCPServer: Video streamming started");
            vthread.videoStream = true;
        }
    }


    /*
     * `s the server process
     */
    public void stop() {
        System.out.println("TCPServer: Stopping server");
        flag = false;

        //Stopping video if it is running
        if(vthread != null) {
            vthread.stopVideo();
            vthread = null;
        }
        System.out.println("TCPServer: Video stopped");

        //Closing server socket
        if(serverSocket != null) {
            try {
                serverSocket.close();
                System.out.println("TCPServer: Server Socket Closed");
            } catch (IOException e) {
                e.printStackTrace();
                System.out.println("TCPServer: Error while closing socket");
            }
            serverSocket = null;
        }
    }
}

Bitte jemand mir sagen, wie ich telnet funktioniert(oder mir sagen, wo ich finde ich ein tutorial auf, dass). Ich habe den obigen code. Habe ich ändern Sie den obigen code(die funktioniert für blutooth) in die telnet-code(die funktioniert auch für WLAN).