org.apache.commons.net.telnet

Class TelnetOptionHandler

java.lang.Object

org.apache.commons.net.telnet.TelnetOptionHandler

Direct Known Subclasses:

EchoOptionHandler, SimpleOptionHandler, SuppressGAOptionHandler, TerminalTypeOptionHandler, WindowSizeOptionHandler

public abstract class TelnetOptionHandler
extends Object

The TelnetOptionHandler class is the base class to be used for implementing handlers for Telnet options.

TelnetOptionHandler implements basic option handling functionality and defines abstract methods that must be implemented to define subnegotiation behavior.

Constructor Summary

Constructors

Constructor and Description
TelnetOptionHandler(int optcode, boolean initlocal, boolean initremote, boolean acceptlocal, boolean acceptremote) Constructor for the TelnetOptionHandler.

Method Summary

Modifier and Type	Method and Description
int[]	answerSubnegotiation(int[] suboptionData, int suboptionLength) Method called upon reception of a subnegotiation for this option coming from the other end.
boolean	getAcceptLocal() Gets a boolean indicating whether to accept a DO request coming from the other end.
boolean	getAcceptRemote() Gets a boolean indicating whether to accept a WILL request coming from the other end.
(package private) boolean	getDo() Gets a boolean indicating whether a DO request sent to the other side has been acknowledged.
boolean	getInitLocal() Gets a boolean indicating whether to send a WILL request to the other end upon connection.
boolean	getInitRemote() Gets a boolean indicating whether to send a DO request to the other end upon connection.
int	getOptionCode() Gets the option code for this option.
(package private) boolean	getWill() Gets a boolean indicating whether a WILL request sent to the other side has been acknowledged.
void	setAcceptLocal(boolean accept) Sets behavior of the option for DO requests coming from the other end.
void	setAcceptRemote(boolean accept) Sets behavior of the option for WILL requests coming from the other end.
(package private) void	setDo(boolean state) Sets this option whether a DO request sent to the other side has been acknowledged (invoked by TelnetClient).
void	setInitLocal(boolean init) Sets this option whether to send a WILL request upon connection.
void	setInitRemote(boolean init) Sets this option whether to send a DO request upon connection.
(package private) void	setWill(boolean state) Sets this option whether a WILL request sent to the other side has been acknowledged (invoked by TelnetClient).
int[]	startSubnegotiationLocal() This method is invoked whenever this option is acknowledged active on the local end (TelnetClient sent a WILL, remote side sent a DO).
int[]	startSubnegotiationRemote() This method is invoked whenever this option is acknowledged active on the remote end (TelnetClient sent a DO, remote side sent a WILL).

Methods inherited from class java.lang.Object

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

Constructor Detail

TelnetOptionHandler

public TelnetOptionHandler(int optcode,
                           boolean initlocal,
                           boolean initremote,
                           boolean acceptlocal,
                           boolean acceptremote)

Constructor for the TelnetOptionHandler. Allows defining desired initial setting for local/remote activation of this option and behavior in case a local/remote activation request for this option is received.

Parameters:

optcode - Option code.

initlocal - if set to true, a WILL is sent upon connection.

initremote - if set to true, a DO is sent upon connection.

acceptlocal - if set to true, any DO request is accepted.

acceptremote - if set to true, any WILL request is accepted.

Method Detail

answerSubnegotiation

public int[] answerSubnegotiation(int[] suboptionData,
                                  int suboptionLength)

Method called upon reception of a subnegotiation for this option coming from the other end.

This implementation returns null, and must be overridden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

Parameters:

suboptionData - the sequence received, without IAC SB & IAC SE

suboptionLength - the length of data in suboption_data

Returns:

response to be sent to the subnegotiation sequence. TelnetClient will add IAC SB & IAC SE. null means no response

getAcceptLocal

public boolean getAcceptLocal()

Gets a boolean indicating whether to accept a DO request coming from the other end.

Returns:

true if a DO request shall be accepted.

getAcceptRemote

public boolean getAcceptRemote()

Gets a boolean indicating whether to accept a WILL request coming from the other end.

Returns:

true if a WILL request shall be accepted.

getDo

boolean getDo()

Gets a boolean indicating whether a DO request sent to the other side has been acknowledged.

Returns:

true if a DO sent to the other side has been acknowledged.

getInitLocal

public boolean getInitLocal()

Gets a boolean indicating whether to send a WILL request to the other end upon connection.

Returns:

true if a WILL request shall be sent upon connection.

getInitRemote

public boolean getInitRemote()

Gets a boolean indicating whether to send a DO request to the other end upon connection.

Returns:

true if a DO request shall be sent upon connection.

getOptionCode

public int getOptionCode()

Gets the option code for this option.

Returns:

Option code.

getWill

boolean getWill()

Gets a boolean indicating whether a WILL request sent to the other side has been acknowledged.

Returns:

true if a WILL sent to the other side has been acknowledged.

setAcceptLocal

public void setAcceptLocal(boolean accept)

Sets behavior of the option for DO requests coming from the other end.

Parameters:

accept - if true, subsequent DO requests will be accepted.

setAcceptRemote

public void setAcceptRemote(boolean accept)

Sets behavior of the option for WILL requests coming from the other end.

Parameters:

accept - if true, subsequent WILL requests will be accepted.

setDo

void setDo(boolean state)

Sets this option whether a DO request sent to the other side has been acknowledged (invoked by TelnetClient).

Parameters:

state - if true, a DO request has been acknowledged.

setInitLocal

public void setInitLocal(boolean init)

Sets this option whether to send a WILL request upon connection.

Parameters:

init - if true, a WILL request will be sent upon subsequent connections.

setInitRemote

public void setInitRemote(boolean init)

Sets this option whether to send a DO request upon connection.

Parameters:

init - if true, a DO request will be sent upon subsequent connections.

setWill

void setWill(boolean state)

Sets this option whether a WILL request sent to the other side has been acknowledged (invoked by TelnetClient).

Parameters:

state - if true, a WILL request has been acknowledged.

startSubnegotiationLocal

public int[] startSubnegotiationLocal()

This method is invoked whenever this option is acknowledged active on the local end (TelnetClient sent a WILL, remote side sent a DO). The method is used to specify a subnegotiation sequence that will be sent by TelnetClient when the option is activated.

This implementation returns null, and must be overriden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

Returns:

subnegotiation sequence to be sent by TelnetClient. TelnetClient will add IAC SB & IAC SE. null means no subnegotiation.

startSubnegotiationRemote

public int[] startSubnegotiationRemote()

This method is invoked whenever this option is acknowledged active on the remote end (TelnetClient sent a DO, remote side sent a WILL). The method is used to specify a subnegotiation sequence that will be sent by TelnetClient when the option is activated.

This implementation returns null, and must be overridden by the actual TelnetOptionHandler to specify which response must be sent for the subnegotiation request.

Returns:

subnegotiation sequence to be sent by TelnetClient. TelnetClient will add IAC SB & IAC SE. null means no subnegotiation.