groovyx.gpars.util
Class AsyncMessagingCore

java.lang.Object
  groovyx.gpars.util.AsyncMessagingCore

All Implemented Interfaces:

java.lang.Runnable

public abstract class AsyncMessagingCore
extends java.lang.Object
implements java.lang.Runnable

Author:

Vaclav Pech Date: Aug 23, 2010

Field Summary

private int	active Indicates, whether there's an active thread handling a message inside the agent's body
private static int	ACTIVE
private static java.util.concurrent.atomic.AtomicIntegerFieldUpdater<AsyncMessagingCore>	activeUpdater
private boolean	fair Fair agents give up the thread after processing each message, non-fair agents keep a thread until their message queue is empty.
private static int	PASSIVE
private MessageQueue	queue Incoming messages
private Pool	threadPool

Constructor Summary

protected

AsyncMessagingCore(Pool threadPool)

Method Summary

void	attachToThreadPool(Pool threadPool) Sets a new thread pool to be used by the agent
protected boolean	continueProcessingMessages() Informs about a new thread being assigned to process the next message
(package private) Pool	getThreadPool()
protected abstract void	handleMessage(java.lang.Object message)
boolean	isFair() Retrieves the agent's fairness flag Fair agents give up the thread after processing each message, non-fair agents keep a thread until their message queue is empty.
void	makeFair() Makes the agent fair.
protected abstract void	registerError(java.lang.Throwable e)
void	run() Handles a single message from the message queue
(package private) void	schedule() Schedules processing of a next message, if there are some and if there isn't an active thread handling a message at the moment
void	store(java.lang.Object message) Adds the message to the agent\s message queue
java.lang.Object	sweepNextMessage() Removes the head of the message queue
protected void	threadAssigned() Informs about the thread being removed from the task
protected void	threadUnassigned() Informs about a new thread being assigned to process the next message

Methods inherited from class java.lang.Object

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

Field Detail

threadPool

private Pool threadPool

fair

private volatile boolean fair

Fair agents give up the thread after processing each message, non-fair agents keep a thread until their message queue is empty.

queue

private final MessageQueue queue

Incoming messages

active

private volatile int active

Indicates, whether there's an active thread handling a message inside the agent's body

activeUpdater

private static final java.util.concurrent.atomic.AtomicIntegerFieldUpdater<AsyncMessagingCore> activeUpdater

PASSIVE

private static final int PASSIVE

See Also:

Constant Field Values

ACTIVE

private static final int ACTIVE

See Also:

Constant Field Values

Constructor Detail

AsyncMessagingCore

protected AsyncMessagingCore(Pool threadPool)

Method Detail

attachToThreadPool

public final void attachToThreadPool(Pool threadPool)

Sets a new thread pool to be used by the agent

Parameters:

threadPool - The thread pool to use

getThreadPool

Pool getThreadPool()

isFair

public boolean isFair()

Retrieves the agent's fairness flag Fair agents give up the thread after processing each message, non-fair agents keep a thread until their message queue is empty. Non-fair agents tend to perform better than fair ones.

Returns:

True for fair agents, false for non-fair ones. Agents are non-fair by default.

makeFair

public void makeFair()

Makes the agent fair. Agents are non-fair by default. Fair agents give up the thread after processing each message, non-fair agents keep a thread until their message queue is empty. Non-fair agents tend to perform better than fair ones.

store

public void store(java.lang.Object message)

Adds the message to the agent\s message queue

Parameters:

message - A value or a closure

schedule

void schedule()

Schedules processing of a next message, if there are some and if there isn't an active thread handling a message at the moment

sweepNextMessage

public java.lang.Object sweepNextMessage()

Removes the head of the message queue

Returns:

The head message, or null, if the message queue is empty

run

public final void run()

Handles a single message from the message queue

Specified by:

run in interface java.lang.Runnable

continueProcessingMessages

protected boolean continueProcessingMessages()

Informs about a new thread being assigned to process the next message

Returns:

True, if the calculation should proceed

threadUnassigned

protected void threadUnassigned()

Informs about a new thread being assigned to process the next message

threadAssigned

protected void threadAssigned()

Informs about the thread being removed from the task

registerError

protected abstract void registerError(java.lang.Throwable e)

handleMessage

protected abstract void handleMessage(java.lang.Object message)