Package anecho.extranet

Class TelnetProtocolHandler

java.lang.Object

anecho.extranet.TelnetProtocolHandler

Direct Known Subclasses:

JMUDTelnetProtocolHandler

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

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	ID	contains the current revision id

Constructor Summary

Constructors

Constructor	Description
TelnetProtocolHandler()	Create a new telnet protocol handler.

Method Summary

Modifier and Type	Method	Description
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)
boolean	isMCCP2()	This method returns whether MCCP2 is currently enabled
boolean	isMXP()
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	setWindowSize(int columns, int rows)	Send the new Window Size (via NAWS)
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

See Also:

Constant Field Values

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

Throws:

java.io.IOException

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 )

Throws:

java.io.IOException

setWindowSize

public void setWindowSize(int columns,
                          int rows)
                   throws java.io.IOException

Send the new Window Size (via NAWS)

Throws:

java.io.IOException

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.)

Throws:

java.io.IOException

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

Throws:

java.io.IOException

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:

nbuf - the byte buffer put out after negotiation

Returns:

number of bytes processed, 0 for none, and -1 for end of buffer.

Throws:

java.io.IOException

inputfeed

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

isMCCP2

public boolean isMCCP2()

This method returns whether MCCP2 is currently enabled

Returns:

isMXP

public boolean isMXP()