net.wimpi.telnetd.net
Class Connection

java.lang.Object
  java.lang.Thread
      net.wimpi.telnetd.net.Connection

All Implemented Interfaces:

java.lang.Runnable

public class Connection
extends java.lang.Thread

Class that implements a connection with this telnet daemon.
It is derived from java.lang.Thread, which reflects the architecture constraint of one thread per connection. This might seem a waste of resources, but as a matter of fact sharing threads would require a far more complex imlementation, due to the fact that telnet is not a stateless protocol (i.e. alive throughout a session of multiple requests and responses).
Each Connection instance is created by the listeners ConnectionManager instance, making it part of a threadgroup and passing in an associated ConnectionData instance, that holds vital information about the connection. Be sure to take a look at their documention.

Once the thread has started and is running, it will get a login shell instance from the ShellManager and run passing its own reference.

Version:

2.0 (16/07/2006)

Author:

Dieter Wimberger

See Also:

ConnectionManager, ConnectionData, ShellManager, TerminalIO

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Connection(java.lang.ThreadGroup tcg, ConnectionData cd)
Constructs a TelnetConnection by invoking its parent constructor and setting of various members.
Subsequently instantiates the whole i/o subsystem, negotiating telnet protocol level options etc.

Method Summary

void	addConnectionListener(ConnectionListener cl) Method that registers a ConnectionListener with the Connection instance.
void	close() Closes the connection and its underlying i/o and network resources.
ConnectionData	getConnectionData() Method to access the associated connection data.
BasicTerminalIO	getTerminalIO() Method to access the associated terminal io.
boolean	isActive() Returns if a connection has been closed.
void	processConnectionEvent(ConnectionEvent ce) Method called by the io subsystem to pass on a "low-level" event.
void	removeConnectionListener(ConnectionListener cl) Method that removes a ConnectionListener from the Connection instance.
void	run() Method overloaded to implement following behaviour: On first entry, retrieve an instance of the configured login shell from the ShellManager and run it.
boolean	setNextShell(java.lang.String name) Method to prepare the Connection for a shell switch. A shell instance will be acquired from the ShellManager according to the given name. In case of a nonexistant name the return will be false, otherwise true.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Constructor Detail

Connection

public Connection(java.lang.ThreadGroup tcg,
                  ConnectionData cd)

Constructs a TelnetConnection by invoking its parent constructor and setting of various members.
Subsequently instantiates the whole i/o subsystem, negotiating telnet protocol level options etc.

Parameters:

tcg - ThreadGroup that this instance is running in.

cd - ConnectionData instance containing all vital information of this connection.

See Also:

ConnectionData

Method Detail

run

public void run()

Method overloaded to implement following behaviour:

1. On first entry, retrieve an instance of the configured login shell from the ShellManager and run it.
2. Handle a shell switch or close down disgracefully when problems (i.e. unhandled unchecked exceptions) occur in the running shell.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

getConnectionData

public ConnectionData getConnectionData()

Method to access the associated connection data.

Returns:

ConnectionData associated with the Connection instance.

See Also:

ConnectionData

getTerminalIO

public BasicTerminalIO getTerminalIO()

Method to access the associated terminal io.

Returns:

BasicTerminalIO associated with the Connection instance.

See Also:

BasicTerminalIO

setNextShell

public boolean setNextShell(java.lang.String name)

Method to prepare the Connection for a shell switch.
A shell instance will be acquired from the ShellManager according to the given name.
In case of a nonexistant name the return will be false, otherwise true.

Parameters:

name - String that should represent a valid shell name.

Returns:

boolean flagging if the request could be carried out correctly.

See Also:

ShellManager

close

public void close()

Closes the connection and its underlying i/o and network resources.

isActive

public boolean isActive()

Returns if a connection has been closed.

Returns:

the state of the connection.

addConnectionListener

public void addConnectionListener(ConnectionListener cl)

Method that registers a ConnectionListener with the Connection instance.

Parameters:

cl - ConnectionListener to be registered.

See Also:

ConnectionListener

removeConnectionListener

public void removeConnectionListener(ConnectionListener cl)

Method that removes a ConnectionListener from the Connection instance.

Parameters:

cl - ConnectionListener to be removed.

See Also:

ConnectionListener

processConnectionEvent

public void processConnectionEvent(ConnectionEvent ce)

Method called by the io subsystem to pass on a "low-level" event. It will be properly delegated to all registered listeners.

Parameters:

ce - ConnectionEvent to be processed.

See Also:

ConnectionEvent