http://commons.apache.org/proper/commons-net/: Apache Commons Net library contains a collection of network utilities and protocol implementations. Supported protocols include: Echo, Finger, FTP, NNTP, NTP, POP3(S), SMTP(S), Telnet, Whois (The Apache Software Foundation)
  • Henrik Sorensen
  • Jeff Nadler
  • William Noto
  • Stephane ESTE-GRACIAS
  • Dan Armbrust
  • Yuval Kashtan
  • Joseph Hindsley
  • Rob Hasselbaum
  • Mario Ivankovits
  • Naz Irizarry (MITRE Corp)
  • Tapan Karecha
  • Jason Mathews (MITRE Corp)
  • Winston Ojeda (Quad/Graphics, Inc.)
  • Ted Wise
  • Bogdan Drozdowski
  • Jeffrey D. Brekke (Quad/Graphics, Inc.)
  • Steve Cohen (javactivity.org)
  • Bruno D'Avanzo (Hewlett-Packard)
  • Daniel F. Savarese (<a href="http://www.savarese.com/">Savarese Software Research</a>)
  • Rory Winston ()
  • Rory Winston () 
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.commons.net.telnet;


The TelnetCommand class cannot be instantiated and only serves as a
storehouse for telnet command constants.

See Also:
/**
 * The TelnetCommand class cannot be instantiated and only serves as a
 * storehouse for telnet command constants.
 * @see org.apache.commons.net.telnet.Telnet
 * @see org.apache.commons.net.telnet.TelnetClient
 */

public final class TelnetCommand
{
    
The maximum value a command code can have.  This value is 255. 
/*** The maximum value a command code can have.  This value is 255. ***/
    public static final int MAX_COMMAND_VALUE = 255;

    
Interpret As Command code.  Value is 255 according to RFC 854. 
/*** Interpret As Command code.  Value is 255 according to RFC 854. ***/
    public static final int IAC = 255;

    
Don't use option code.  Value is 254 according to RFC 854. 
/*** Don't use option code.  Value is 254 according to RFC 854. ***/
    public static final int DONT = 254;

    
Request to use option code.  Value is 253 according to RFC 854. 
/*** Request to use option code.  Value is 253 according to RFC 854. ***/
    public static final int DO = 253;

    
Refuse to use option code.  Value is 252 according to RFC 854. 
/*** Refuse to use option code.  Value is 252 according to RFC 854. ***/
    public static final int WONT = 252;

    
Agree to use option code.  Value is 251 according to RFC 854. 
/*** Agree to use option code.  Value is 251 according to RFC 854. ***/
    public static final int WILL = 251;

    
Start subnegotiation code.  Value is 250 according to RFC 854. 
/*** Start subnegotiation code.  Value is 250 according to RFC 854. ***/
    public static final int SB = 250;

    
Go Ahead code.  Value is 249 according to RFC 854. 
/*** Go Ahead code.  Value is 249 according to RFC 854. ***/
    public static final int GA = 249;

    
Erase Line code.  Value is 248 according to RFC 854. 
/*** Erase Line code.  Value is 248 according to RFC 854. ***/
    public static final int EL = 248;

    
Erase Character code.  Value is 247 according to RFC 854. 
/*** Erase Character code.  Value is 247 according to RFC 854. ***/
    public static final int EC = 247;

    
Are You There code.  Value is 246 according to RFC 854. 
/*** Are You There code.  Value is 246 according to RFC 854. ***/
    public static final int AYT = 246;

    
Abort Output code.  Value is 245 according to RFC 854. 
/*** Abort Output code.  Value is 245 according to RFC 854. ***/
    public static final int AO = 245;

    
Interrupt Process code.  Value is 244 according to RFC 854. 
/*** Interrupt Process code.  Value is 244 according to RFC 854. ***/
    public static final int IP = 244;

    
Break code.  Value is 243 according to RFC 854. 
/*** Break code.  Value is 243 according to RFC 854. ***/
    public static final int BREAK = 243;

    
Data mark code.  Value is 242 according to RFC 854. 
/*** Data mark code.  Value is 242 according to RFC 854. ***/
    public static final int DM = 242;

    
No Operation code.  Value is 241 according to RFC 854. 
/*** No Operation code.  Value is 241 according to RFC 854. ***/
    public static final int NOP = 241;

    
End subnegotiation code.  Value is 240 according to RFC 854. 
/*** End subnegotiation code.  Value is 240 according to RFC 854. ***/
    public static final int SE = 240;

    
End of record code.  Value is 239. 
/*** End of record code.  Value is 239. ***/
    public static final int EOR = 239;

    
Abort code.  Value is 238. 
/*** Abort code.  Value is 238. ***/
    public static final int ABORT = 238;

    
Suspend process code.  Value is 237. 
/*** Suspend process code.  Value is 237. ***/
    public static final int SUSP = 237;

    
End of file code.  Value is 236. 
/*** End of file code.  Value is 236. ***/
    public static final int EOF = 236;

    
Synchronize code.  Value is 242. 
/*** Synchronize code.  Value is 242. ***/
    public static final int SYNCH = 242;

    
String representations of commands. 
/*** String representations of commands. ***/
    private static final String __commandString[] = {
                "IAC", "DONT", "DO", "WONT", "WILL", "SB", "GA", "EL", "EC", "AYT",
                "AO", "IP", "BRK", "DMARK", "NOP", "SE", "EOR", "ABORT", "SUSP", "EOF"
            };

    private static final int __FIRST_COMMAND = IAC;
    private static final int __LAST_COMMAND = EOF;

    
Returns the string representation of the telnet protocol command
corresponding to the given command code.



Params:
  • code – The command code of the telnet protocol command.
Returns:The string representation of the telnet protocol command.
/***
     * Returns the string representation of the telnet protocol command
     * corresponding to the given command code.
     * <p>
     * @param code The command code of the telnet protocol command.
     * @return The string representation of the telnet protocol command.
     ***/
    public static final String getCommand(int code)
    {
        return __commandString[__FIRST_COMMAND - code];
    }

    
Determines if a given command code is valid.  Returns true if valid,
false if not.



Params:
  • code –  The command code to test.
Returns:True if the command code is valid, false if not.
/***
     * Determines if a given command code is valid.  Returns true if valid,
     * false if not.
     * <p>
     * @param code  The command code to test.
     * @return True if the command code is valid, false if not.
     **/
    public static final boolean isValidCommand(int code)
    {
        return (code <= __FIRST_COMMAND && code >= __LAST_COMMAND);
    }

    // Cannot be instantiated
    private TelnetCommand()
    { }
}