com.maverick.ssh.message

Class SshMessageRouter

java.lang.Object

com.maverick.ssh.message.SshMessageRouter

public abstract class SshMessageRouter
extends Object

This abstract class provides a synchronized message routing framework that can be used for both the SSH1 and SSH2 protocols. The protocol implementation supplies a message reader interface, to which only one thread is allowed access at any one time, threads requiring a message whilst another thread is blocking are queued to await notification of when the reader is available. Since a message read by one thread may be destined for another the router takes charge of this before notifying other queued threads that the block is available. When they receive this notification they first check their own message stores before requesting the block again.

Author:

Lee David Painter

Constructor Summary

Constructors

Constructor and Description
SshMessageRouter(SshMessageReader reader, int maxChannels, boolean buffered)

Method Summary

Modifier and Type	Method and Description
void	addShutdownHook(Runnable r)
protected int	allocateChannel(SshAbstractChannel channel)
void	blockForMessage(long timeout)
protected abstract SshMessage	createMessage(byte[] msg) Called by the message routing framework to request the creation of an SshMessage.
protected void	freeChannel(SshAbstractChannel channel)
protected SshAbstractChannel[]	getActiveChannels()
Thread	getBackgroundThread()
int	getChannelCount()
protected SshMessageStore	getGlobalMessages()
int	getMaxChannels()
SshMessageReader	getReader()
boolean	hasBackgroundThread()
boolean	isBlockingThread(Thread thread)
boolean	isBuffered()
protected int	maximumChannels()
protected SshMessage	nextMessage(SshAbstractChannel channel, MessageObserver observer, long timeout)
protected abstract void	onThreadExit() Called when the threaded router closes.
protected abstract boolean	processGlobalMessage(SshMessage msg) Called by the message routing framework so that the routing implementation may process a global message.
void	signalClosingState()
void	start()
void	stop()

Methods inherited from class java.lang.Object

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

Constructor Detail

SshMessageRouter

public SshMessageRouter(SshMessageReader reader,
                        int maxChannels,
                        boolean buffered)

Method Detail

getReader

public SshMessageReader getReader()

getBackgroundThread

public Thread getBackgroundThread()

hasBackgroundThread

public boolean hasBackgroundThread()

start

public void start()

addShutdownHook

public void addShutdownHook(Runnable r)

isBuffered

public boolean isBuffered()

stop

public void stop()

signalClosingState

public void signalClosingState()

getGlobalMessages

protected SshMessageStore getGlobalMessages()

getMaxChannels

public int getMaxChannels()

allocateChannel

protected int allocateChannel(SshAbstractChannel channel)

freeChannel

protected void freeChannel(SshAbstractChannel channel)

getActiveChannels

protected SshAbstractChannel[] getActiveChannels()

maximumChannels

protected int maximumChannels()

getChannelCount

public int getChannelCount()

nextMessage

protected SshMessage nextMessage(SshAbstractChannel channel,
                                 MessageObserver observer,
                                 long timeout)
                          throws SshException,
                                 InterruptedException

Throws:

SshException

InterruptedException

isBlockingThread

public boolean isBlockingThread(Thread thread)

blockForMessage

public void blockForMessage(long timeout)
                     throws SshException

Throws:

SshException

onThreadExit

protected abstract void onThreadExit()

Called when the threaded router closes.

createMessage

protected abstract SshMessage createMessage(byte[] msg)
                                     throws SshException

Called by the message routing framework to request the creation of an SshMessage.

Parameters:

messageid -

Returns:

the new message instance

Throws:

SshException

processGlobalMessage

protected abstract boolean processGlobalMessage(SshMessage msg)
                                         throws SshException

Called by the message routing framework so that the routing implementation may process a global message. If the message is processed and no further action is required this method should return true, if the method returns false then the message will be added to the global message store.

Parameters:

msg -

Returns:

true if the message was processed, otherwise false

Throws:

IOException

SshException