Java/Network Protocol/Telnet

Example of use of Telnet Client

/*
 * Copyright 2003-2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package examples;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.rumons.net.telnet.TelnetClient;
import org.apache.rumons.net.telnet.TelnetNotificationHandler;
import org.apache.rumons.net.telnet.SimpleOptionHandler;
import org.apache.rumons.net.telnet.EchoOptionHandler;
import org.apache.rumons.net.telnet.TerminalTypeOptionHandler;
import org.apache.rumons.net.telnet.SuppressGAOptionHandler;
import org.apache.rumons.net.telnet.InvalidTelnetOptionException;
import java.util.StringTokenizer;

/***
 * This is a simple example of use of TelnetClient.
 * An external option handler (SimpleTelnetOptionHandler) is used.
 * Initial configuration requested by TelnetClient will be:
 * WILL ECHO, WILL SUPPRESS-GA, DO SUPPRESS-GA.
 * VT100 terminal type will be subnegotiated.
 * <p>
 * Also, use of the sendAYT(), getLocalOptionState(), getRemoteOptionState()
 * is demonstrated.
 * When connected, type AYT to send an AYT command to the server and see
 * the result.
 * Type OPT to see a report of the state of the first 25 options.
 * <p>
 * @author Bruno D"Avanzo
 ***/
public class TelnetClientExample implements Runnable, TelnetNotificationHandler
{
    static TelnetClient tc = null;
    /***
     * Main for the TelnetClientExample.
     ***/
    public static void main(String[] args) throws IOException
    {
        FileOutputStream fout = null;
        if(args.length < 1)
        {
            System.err.println("Usage: TelnetClientExample1 <remote-ip> [<remote-port>]");
            System.exit(1);
        }
        String remoteip = args[0];
        int remoteport;
        if (args.length > 1)
        {
            remoteport = (new Integer(args[1])).intValue();
        }
        else
        {
            remoteport = 23;
        }
        try
        {
            fout = new FileOutputStream ("spy.log", true);
        }
        catch (Exception e)
        {
            System.err.println(
                "Exception while opening the spy file: "
                + e.getMessage());
        }
        tc = new TelnetClient();
        TerminalTypeOptionHandler ttopt = new TerminalTypeOptionHandler("VT100", false, false, true, false);
        EchoOptionHandler echoopt = new EchoOptionHandler(true, false, true, false);
        SuppressGAOptionHandler gaopt = new SuppressGAOptionHandler(true, true, true, true);
        try
        {
            tc.addOptionHandler(ttopt);
            tc.addOptionHandler(echoopt);
            tc.addOptionHandler(gaopt);
        }
        catch (InvalidTelnetOptionException e)
        {
            System.err.println("Error registering option handlers: " + e.getMessage());
        }
        while (true)
        {
            boolean end_loop = false;
            try
            {
                tc.connect(remoteip, remoteport);

                Thread reader = new Thread (new TelnetClientExample());
                tc.registerNotifHandler(new TelnetClientExample());
                System.out.println("TelnetClientExample");
                System.out.println("Type AYT to send an AYT telnet command");
                System.out.println("Type OPT to print a report of status of options (0-24)");
                System.out.println("Type REGISTER to register a new SimpleOptionHandler");
                System.out.println("Type UNREGISTER to unregister an OptionHandler");
                System.out.println("Type SPY to register the spy (connect to port 3333 to spy)");
                System.out.println("Type UNSPY to stop spying the connection");
                reader.start();
                OutputStream outstr = tc.getOutputStream();
                byte[] buff = new byte[1024];
                int ret_read = 0;
                do
                {
                    try
                    {
                        ret_read = System.in.read(buff);
                        if(ret_read > 0)
                        {
                            if((new String(buff, 0, ret_read)).startsWith("AYT"))
                            {
                                try
                                {
                                    System.out.println("Sending AYT");
                                    System.out.println("AYT response:" + tc.sendAYT(5000));
                                }
                                catch (Exception e)
                                {
                                    System.err.println("Exception waiting AYT response: " + e.getMessage());
                                }
                            }
                            else if((new String(buff, 0, ret_read)).startsWith("OPT"))
                            {
                                 System.out.println("Status of options:");
                                 for(int ii=0; ii<25; ii++)
                                    System.out.println("Local Option " + ii + ":" + tc.getLocalOptionState(ii) + " Remote Option " + ii + ":" + tc.getRemoteOptionState(ii));
                            }
                            else if((new String(buff, 0, ret_read)).startsWith("REGISTER"))
                            {
                                StringTokenizer st = new StringTokenizer(new String(buff));
                                try
                                {
                                    st.nextToken();
                                    int opcode = (new Integer(st.nextToken())).intValue();
                                    boolean initlocal = (new Boolean(st.nextToken())).booleanValue();
                                    boolean initremote = (new Boolean(st.nextToken())).booleanValue();
                                    boolean acceptlocal = (new Boolean(st.nextToken())).booleanValue();
                                    boolean acceptremote = (new Boolean(st.nextToken())).booleanValue();
                                    SimpleOptionHandler opthand = new SimpleOptionHandler(opcode, initlocal, initremote,
                                                                    acceptlocal, acceptremote);
                                    tc.addOptionHandler(opthand);
                                }
                                catch (Exception e)
                                {
                                    if(e instanceof InvalidTelnetOptionException)
                                    {
                                        System.err.println("Error registering option: " + e.getMessage());
                                    }
                                    else
                                    {
                                        System.err.println("Invalid REGISTER command.");
                                        System.err.println("Use REGISTER optcode initlocal initremote acceptlocal acceptremote");
                                        System.err.println("(optcode is an integer.)");
                                        System.err.println("(initlocal, initremote, acceptlocal, acceptremote are boolean)");
                                    }
                                }
                            }
                            else if((new String(buff, 0, ret_read)).startsWith("UNREGISTER"))
                            {
                                StringTokenizer st = new StringTokenizer(new String(buff));
                                try
                                {
                                    st.nextToken();
                                    int opcode = (new Integer(st.nextToken())).intValue();
                                    tc.deleteOptionHandler(opcode);
                                }
                                catch (Exception e)
                                {
                                    if(e instanceof InvalidTelnetOptionException)
                                    {
                                        System.err.println("Error unregistering option: " + e.getMessage());
                                    }
                                    else
                                    {
                                        System.err.println("Invalid UNREGISTER command.");
                                        System.err.println("Use UNREGISTER optcode");
                                        System.err.println("(optcode is an integer)");
                                    }
                                }
                            }
                            else if((new String(buff, 0, ret_read)).startsWith("SPY"))
                            {
                                try
                                {
                                    tc.registerSpyStream(fout);
                                }
                                catch (Exception e)
                                {
                                    System.err.println("Error registering the spy");
                                }
                            }
                            else if((new String(buff, 0, ret_read)).startsWith("UNSPY"))
                            {
                                tc.stopSpyStream();
                            }
                            else
                            {
                                try
                                {
                                        outstr.write(buff, 0 , ret_read);
                                        outstr.flush();
                                }
                                catch (Exception e)
                                {
                                        end_loop = true;
                                }
                            }
                        }
                    }
                    catch (Exception e)
                    {
                        System.err.println("Exception while reading keyboard:" + e.getMessage());
                        end_loop = true;
                    }
                }
                while((ret_read > 0) && (end_loop == false));
                try
                {
                    tc.disconnect();
                }
                catch (Exception e)
                {
                          System.err.println("Exception while connecting:" + e.getMessage());
                }
            }
            catch (Exception e)
            {
                    System.err.println("Exception while connecting:" + e.getMessage());
                    System.exit(1);
            }
        }
    }

    /***
     * Callback method called when TelnetClient receives an option
     * negotiation command.
     * <p>
     * @param negotiation_code - type of negotiation command received
     * (RECEIVED_DO, RECEIVED_DONT, RECEIVED_WILL, RECEIVED_WONT)
     * <p>
     * @param option_code - code of the option negotiated
     * <p>
     ***/
    public void receivedNegotiation(int negotiation_code, int option_code)
    {
        String command = null;
        if(negotiation_code == TelnetNotificationHandler.RECEIVED_DO)
        {
            command = "DO";
        }
        else if(negotiation_code == TelnetNotificationHandler.RECEIVED_DONT)
        {
            command = "DONT";
        }
        else if(negotiation_code == TelnetNotificationHandler.RECEIVED_WILL)
        {
            command = "WILL";
        }
        else if(negotiation_code == TelnetNotificationHandler.RECEIVED_WONT)
        {
            command = "WONT";
        }
        System.out.println("Received " + command + " for option code " + option_code);
   }
    /***
     * Reader thread.
     * Reads lines from the TelnetClient and echoes them
     * on the screen.
     ***/
    public void run()
    {
        InputStream instr = tc.getInputStream();
        try
        {
            byte[] buff = new byte[1024];
            int ret_read = 0;
            do
            {
                ret_read = instr.read(buff);
                if(ret_read > 0)
                {
                    System.out.print(new String(buff, 0, ret_read));
                }
            }
            while (ret_read >= 0);
        }
        catch (Exception e)
        {
            System.err.println("Exception while reading socket:" + e.getMessage());
        }
        try
        {
            tc.disconnect();
        }
        catch (Exception e)
        {
            System.err.println("Exception while closing telnet:" + e.getMessage());
        }
    }
}

TelnetClient: connects to the weather server at the University of Michigan

/*
 * Copyright 2001-2005 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package examples;
import java.io.IOException;
import org.apache.rumons.net.telnet.TelnetClient;
/***
 * This is an example of a trivial use of the TelnetClient class.
 * It connects to the weather server at the University of Michigan,
 * um-weather.sprl.umich.edu port 3000, and allows the user to interact
 * with the server via standard input.  You could use this example to
 * connect to any telnet server, but it is obviously not general purpose
 * because it reads from standard input a line at a time, making it
 * inconvenient for use with a remote interactive shell.  The TelnetClient
 * class used by itself is mostly intended for automating access to telnet
 * resources rather than interactive use.
 * <p>
 ***/
// This class requires the IOUtil support class!
public class weatherTelnet
{
    public final static void main(String[] args)
    {
        TelnetClient telnet;
        telnet = new TelnetClient();
        try
        {
            telnet.connect("rainmaker.wunderground.ru", 3000);
        }
        catch (IOException e)
        {
            e.printStackTrace();
            System.exit(1);
        }
        IOUtil.readWrite(telnet.getInputStream(), telnet.getOutputStream(),
                         System.in, System.out);
        try
        {
            telnet.disconnect();
        }
        catch (IOException e)
        {
            e.printStackTrace();
            System.exit(1);
        }
        System.exit(0);
    }
}