org.topoweb.net.server
Class SessionAcceptor

java.lang.Object
  |
  +--org.topoweb.net.server.SessionAcceptor

All Implemented Interfaces:

java.lang.Runnable, org.topoweb.util.concurrent.SingleRun

public class SessionAcceptor

extends java.lang.Object

implements org.topoweb.util.concurrent.SingleRun

A org.topoweb.util.concurrent.SingleRun that accepts sockets and pushes them onto an event queue. This class should be run in a single thread and then only once.

Author:

Babak Farhang

Field Summary

protected static java.util.logging.Logger

LOGGER

Constructor Summary

SessionAcceptor(java.net.InetSocketAddress address, SessionPool sessionPool, org.topoweb.util.concurrent.Puttable sessionQueue)
Creates a new instance with the given parameters.

Method Summary

protected void	clean() Frees all the network resources of this instance.
protected boolean	enqueue(Session session) Enqueue's the given session in the queue.
void	init() Initializes the instance.
boolean	isAlive()
void	join(int timeout)
void	run() Runs the acceptor loop.
void	stop()

Methods inherited from class java.lang.Object

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

Field Detail

LOGGER

protected static final java.util.logging.Logger LOGGER

Constructor Detail

SessionAcceptor

public SessionAcceptor(java.net.InetSocketAddress address,
                       SessionPool sessionPool,
                       org.topoweb.util.concurrent.Puttable sessionQueue)
                throws java.lang.IllegalArgumentException

Creates a new instance with the given parameters.

Parameters:

address - the address specifying the host and port of the server this instance represents

sessionPool - a pool/factory for creating Session instances from accepted sockets

sessionQueue - a queue used to schedule the processing of Session instances

Method Detail

init

public void init()
          throws java.lang.IllegalStateException,
                 java.io.IOException

Initializes the instance. The server socket channel is opened and bound to the address passed in at instantiation. An internal selector is created and the server socket channel is registered with the selector for ACCEPT_OPs. Overriding subclasses must invoke super.init().

Throws:

java.lang.IllegalStateException - if this method has already been invoked

java.io.IOException - if an I/O error occurs

run

public void run()
         throws java.lang.IllegalStateException

Runs the acceptor loop. The loop waits on the internal selector for notification of "acceptable" sockets. It then accepts these new sockets and constructs Session instances from them using the SessionPool instance passed in at instantation. These Session instances are then pushed on to the event queue (the Puttable sessionQueue parameter passed in at instantation) for processing by another stage.

The acceptor loop can be signaled to stop through the stop method.

Specified by:

run in interface org.topoweb.util.concurrent.SingleRun

Throws:

java.lang.IllegalStateException - if the instance was not first initialized; if invoked more than once

See Also:

init(), stop()

stop

public void stop()
          throws java.lang.IllegalStateException

Specified by:

stop in interface org.topoweb.util.concurrent.SingleRun

java.lang.IllegalStateException

isAlive

public boolean isAlive()

Specified by:

isAlive in interface org.topoweb.util.concurrent.SingleRun

join

public void join(int timeout)
          throws java.lang.InterruptedException

Specified by:

join in interface org.topoweb.util.concurrent.SingleRun

java.lang.InterruptedException

enqueue

protected boolean enqueue(Session session)

Enqueue's the given session in the queue. The basic implementation waits roughly 1 second for the queue operation to succeed.

Parameters:

session - the session to be enqueued

Returns:

true, if successfully enqueued; false, o.w.

clean

protected void clean()

Frees all the network resources of this instance.