de.mud.telnet
Class TelnetProtocolHandler

java.lang.Object
  |
  +--de.mud.telnet.TelnetProtocolHandler

Direct Known Subclasses:

TelnetWrapper

public abstract class TelnetProtocolHandler

extends java.lang.Object

This is a telnet protocol handler. The handler needs implementations for several methods to handle the telnet options and to be able to read and write the buffer.

Maintainer: Marcus Meißner

Version:

$Id: TelnetProtocolHandler.java,v 2.14 2001/10/07 20:17:43 marcus Exp $

Author:

Matthias L. Jugel, Marcus Meißner

Field Summary

static java.lang.String

ID contains the current revision id

Constructor Summary

TelnetProtocolHandler()
Create a new telnet protocol handler.

Method Summary

protected abstract java.lang.String	getTerminalType() Get the current terminal type for TTYPE telnet option.
protected abstract java.awt.Dimension	getWindowSize() Get the current window size of the terminal for the NAWS telnet option.
void	inputfeed(byte[] b, int len)
int	negotiate(byte[] nbuf) Handle telnet protocol negotiation.
protected abstract void	notifyEndOfRecord() Generate an EOR (end of record) request.
void	reset() Reset the protocol handler.
void	sendTelnetControl(byte code) Send a Telnet Escape character (IAC )
void	setCR(java.lang.String xcr)
void	setCRLF(java.lang.String xcrlf)
protected abstract void	setLocalEcho(boolean echo) Set the local echo option of telnet.
void	startup() Do not send any notifications at startup.
void	transpose(byte[] buf) Transpose special telnet codes like 0xff or newlines to values that are compliant to the protocol.
protected abstract void	write(byte[] b) Send data to the remote host.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ID

public static final java.lang.String ID

contains the current revision id

Constructor Detail

TelnetProtocolHandler

public TelnetProtocolHandler()

Create a new telnet protocol handler.

Method Detail

getTerminalType

protected abstract java.lang.String getTerminalType()

Get the current terminal type for TTYPE telnet option.

Returns:

the string id of the terminal

getWindowSize

protected abstract java.awt.Dimension getWindowSize()

Get the current window size of the terminal for the NAWS telnet option.

Returns:

the size of the terminal as Dimension

setLocalEcho

protected abstract void setLocalEcho(boolean echo)

Set the local echo option of telnet.

Parameters:

echo - true for local echo, false for no local echo

notifyEndOfRecord

protected abstract void notifyEndOfRecord()

Generate an EOR (end of record) request. For use by prompt displaying.

write

protected abstract void write(byte[] b)
                       throws java.io.IOException

Send data to the remote host.

Parameters:

b - array of bytes to send

reset

public void reset()

Reset the protocol handler. This may be necessary after the connection was closed or some other problem occured.

sendTelnetControl

public void sendTelnetControl(byte code)
                       throws java.io.IOException

Send a Telnet Escape character (IAC )

startup

public void startup()
             throws java.io.IOException

Do not send any notifications at startup. We do not know, whether the remote client understands telnet protocol handling, so we are silent. (This used to send IAC WILL SGA, but this is false for a compliant client.)

transpose

public void transpose(byte[] buf)
               throws java.io.IOException

Transpose special telnet codes like 0xff or newlines to values that are compliant to the protocol. This method will also send the buffer immediately after transposing the data.

Parameters:

buf - the data buffer to be sent

setCRLF

public void setCRLF(java.lang.String xcrlf)

setCR

public void setCR(java.lang.String xcr)

negotiate

public int negotiate(byte[] nbuf)
              throws java.io.IOException

Handle telnet protocol negotiation. The buffer will be parsed and necessary actions are taken according to the telnet protocol. See RFC-Telnet

Parameters:

buf - the byte buffer used for negotiation

count - the amount of bytes in the buffer

Returns:

a new buffer after negotiation

inputfeed

public void inputfeed(byte[] b,
                      int len)