org.topoweb.net.server
Class SessionReader

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

All Implemented Interfaces:

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

public class SessionReader

extends java.lang.Object

implements org.topoweb.util.concurrent.SingleRun

An org.topoweb.util.concurrent.SingleRun that reads from sockets. Receives new Sessions from a queue and registers them with an internally managed selector that detects the readiness of sockets for read operations. Reads from sockets until the completion of an interpretable request is detected, and then enqueue's the socket's associated Session for processing by some other agent.

Note:

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 The logger used to log messages.

Constructor Summary

SessionReader(org.topoweb.util.concurrent.Takable readPendingQueue, org.topoweb.util.concurrent.Puttable readCompletedQueue, RequestBoundaryDetector requestDetector, SessionPool sessionPool)
Creates a new instance with the given parameters.

Method Summary

protected boolean	enqueue(Session session) Enqueue's the given session in the read-completed queue.
void	init() Initializes the instance.
boolean	isAlive()
void	join(int timeout)
void	run() Runs the session reader 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

The logger used to log messages. This logger uses this class's package namespace.

Constructor Detail

SessionReader

public SessionReader(org.topoweb.util.concurrent.Takable readPendingQueue,
                     org.topoweb.util.concurrent.Puttable readCompletedQueue,
                     RequestBoundaryDetector requestDetector,
                     SessionPool sessionPool)
              throws java.lang.IllegalArgumentException

Creates a new instance with the given parameters.

Parameters:

readPendingQueue - the queue from which Sessions arrive

readCompletedQueue - the queue on which Sessions are sent once a request has been completely read

requestDetector - the request boundary detector used to tell whether enough bytes have been read to form an interpretable request

sessionPool - the pool to which cancelled Session instances are returned

Throws:

java.lang.IllegalArgumentException - if any of the arguments is null

Method Detail

init

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

Initializes the instance. A new "read-op" selector is opened.

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 session reader loop.

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 read-completed 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.