org.jactr.core.buffer.delegate

Class AsynchronousRequestDelegate

java.lang.Object

org.jactr.core.buffer.delegate.AsynchronousRequestDelegate

All Implemented Interfaces:

IRequestDelegate

Direct Known Subclasses:

AbstractRequestDelegate, AddChunkRequestDelegate, AddChunkTypeRequestDelegate, ImaginalSlotRequestDelegate, OldAsynchronousRequestDelegate, RetrievalRequestDelegate, TimeRequestDelegate

public abstract class AsynchronousRequestDelegate
extends java.lang.Object
implements IRequestDelegate

abstract request delegate that splits requests into two part process startRequest(IRequest, IActivationBuffer, double) and finishRequest(IRequest, IActivationBuffer, Object). This makes it easier to implement asynchronous requests that start a computation and then later harvest the results.

To make derived classes asynchronous, merely override isAsynchronous() to return true, and use computeCompletionTime(double, IRequest, IActivationBuffer) to return when the system should call finishRequest(IRequest, IActivationBuffer, Object).

If finishRequest(IRequest, IActivationBuffer, Object) requires some value from startRequest(IRequest, IActivationBuffer, double) they both have an object that can be passed from one to the other.

The asynchrony is implemented by calling startRequest(IRequest, IActivationBuffer, double) and then queueing up a ITimedEvent that will fire at computeCompletionTime(double, IRequest, IActivationBuffer) which will then call finishRequest(IRequest, IActivationBuffer, Object).

You can also configure the delegate to use blocking timed events to ensure that the model clock does not advance beyond the harvest time (instead of relying upon some blocking mechanism in finishRequest(IRequest, IActivationBuffer, Object). However, if you do enable blocking timed events (setUseBlockingTimedEvents(boolean) ), you must be sure that you call release() in response to some event, otherwise the model will deadlock.


This is for requested that are delayed in time (beyond the current cycle), such as visual requests. As opposed to buffers that accept new chunk insertions directly and immediately (like goal).

Author:

harrison

Constructor Summary

Constructors

Constructor and Description
AsynchronousRequestDelegate()

Method Summary

Modifier and Type	Method and Description
protected void	abortRequest(IRequest request, IActivationBuffer buffer, java.lang.Object startValue) called if the timedevent is aborted
void	clear() clear/cancel any pending requests
protected double	computeCompletionTime(double startTime, IRequest request, IActivationBuffer buffer) default impl returns now + IProceduralModule.getDefaultProductionFiringTime()
protected ITimedEvent	createFinishTimedEvent(double start, double finish, IRequest request, IActivationBuffer buffer, java.lang.Object startValue) creates the timed event that will fire the finish method.
protected IRequest	expandRequest(IRequest request) expand requests gives subclassers the chance to modify the request after it has been validated but before the request is actually made.
protected abstract void	finishRequest(IRequest request, IActivationBuffer buffer, java.lang.Object startValue) finish the request
protected ITimedEvent	getCurrentTimedEvent() returns the last timed event queued.
protected IRequest	getPreviousRequest()
boolean	isAsynchronous() override to return true if the request should be split in time.
protected boolean	isBusy(IActivationBuffer buffer) utility method to test the state, only works if this buffer extends IStatusBuffer
boolean	isDelayingStart()
boolean	isUsingBlockingTimedEvents()
protected abstract boolean	isValid(IRequest request, IActivationBuffer buffer) called the be sure the request is valid.
protected void	postStart(IRequest request, IActivationBuffer buffer, double startTime, double finishTime, java.lang.Object startReturn)
protected void	preStart(IRequest request, IActivationBuffer buffer, double startTime, double finishTime) called just before startRequest(IRequest, IActivationBuffer, double) is called
protected void	release() release the current blocking timed event, if any
boolean	request(IRequest request, IActivationBuffer buffer, double requestTime) make the buffer request.
void	setAsynchronous(boolean isAsynch)
protected void	setBusy(IActivationBuffer buffer) utility method, only works if buffer extends AbstractActivationBuffer6
protected void	setCurrentTimedEvent(ITimedEvent event)
void	setDelayStart(boolean delayStart)
protected void	setError(IActivationBuffer buffer) utility method, only works if buffer extends AbstractActivationBuffer6
protected void	setError(IActivationBuffer buffer, IChunk errorCode)
protected void	setFree(IActivationBuffer buffer) utility method, only works if buffer extends AbstractActivationBuffer6
void	setUseBlockingTimedEvents(boolean use)
protected abstract java.lang.Object	startRequest(IRequest request, IActivationBuffer buffer, double requestTime) Start the buffer request, optimally returning an object for the finishRequest(IRequest, IActivationBuffer, Object) to inspect.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jactr.core.buffer.delegate.IRequestDelegate

willAccept

Constructor Detail

AsynchronousRequestDelegate

public AsynchronousRequestDelegate()

Method Detail

release

protected void release()

release the current blocking timed event, if any

setUseBlockingTimedEvents

public void setUseBlockingTimedEvents(boolean use)

isUsingBlockingTimedEvents

public boolean isUsingBlockingTimedEvents()

isDelayingStart

public boolean isDelayingStart()

setDelayStart

public void setDelayStart(boolean delayStart)

isValid

protected abstract boolean isValid(IRequest request,
                                   IActivationBuffer buffer)
                            throws java.lang.IllegalArgumentException

called the be sure the request is valid. If the request is valid but can't be accepted, return false. If the request is invalid, throw an exception

Parameters:

request -

buffer - TODO

Returns:

Throws:

java.lang.IllegalArgumentException

startRequest

protected abstract java.lang.Object startRequest(IRequest request,
                                                 IActivationBuffer buffer,
                                                 double requestTime)

Start the buffer request, optimally returning an object for the finishRequest(IRequest, IActivationBuffer, Object) to inspect. If this is an asynchronous request, this will be fired and finish will be fired at computeCompletionTime(double, IRequest, IActivationBuffer)

Parameters:

request -

buffer -

requestTime - TODO

finishRequest

protected abstract void finishRequest(IRequest request,
                                      IActivationBuffer buffer,
                                      java.lang.Object startValue)

finish the request

Parameters:

request -

buffer -

startValue -

abortRequest

protected void abortRequest(IRequest request,
                            IActivationBuffer buffer,
                            java.lang.Object startValue)

called if the timedevent is aborted

Parameters:

request -

buffer -

startValue -

clear

public void clear()

Description copied from interface: IRequestDelegate

clear/cancel any pending requests

Specified by:

clear in interface IRequestDelegate

setAsynchronous

public final void setAsynchronous(boolean isAsynch)

isAsynchronous

public final boolean isAsynchronous()

override to return true if the request should be split in time. be sure to override computeCompletionTime(double, IRequest, IActivationBuffer) as well

Returns:

computeCompletionTime

protected double computeCompletionTime(double startTime,
                                       IRequest request,
                                       IActivationBuffer buffer)

default impl returns now + IProceduralModule.getDefaultProductionFiringTime()

Parameters:

now -

request -

buffer - TODO

Returns:

expandRequest

protected IRequest expandRequest(IRequest request)

expand requests gives subclassers the chance to modify the request after it has been validated but before the request is actually made. Subclassers are free to change the request in anyway. This impl merely passes the request through unchanged.

Parameters:

request -

Returns:

request

public final boolean request(IRequest request,
                             IActivationBuffer buffer,
                             double requestTime)

make the buffer request. If synchronous startRequest(IRequest, IActivationBuffer, double) and finishRequest(IRequest, IActivationBuffer, Object) will be called immediately. If not, start will be called and a timed event will be posted that will handle finishRequest(IRequest, IActivationBuffer, Object)

Specified by:

request in interface IRequestDelegate

Parameters:

request -

buffer -

Returns:

See Also:

org.jactr.core.buffer.delegate.IRequestDelegate#request(org.jactr.core.production.request.IRequest, org.jactr.core.buffer.IActivationBuffer)

preStart

protected void preStart(IRequest request,
                        IActivationBuffer buffer,
                        double startTime,
                        double finishTime)

called just before startRequest(IRequest, IActivationBuffer, double) is called

Parameters:

request -

buffer -

startTime -

finishTime -

postStart

protected void postStart(IRequest request,
                         IActivationBuffer buffer,
                         double startTime,
                         double finishTime,
                         java.lang.Object startReturn)

createFinishTimedEvent

protected ITimedEvent createFinishTimedEvent(double start,
                                             double finish,
                                             IRequest request,
                                             IActivationBuffer buffer,
                                             java.lang.Object startValue)

creates the timed event that will fire the finish method. If you want more control, override this method

Parameters:

start -

finish -

request -

buffer -

startValue -

Returns:

getCurrentTimedEvent

protected ITimedEvent getCurrentTimedEvent()

returns the last timed event queued. This will only be changed after each request is called. it will not be nulled out after the event has fired

Returns:

setCurrentTimedEvent

protected void setCurrentTimedEvent(ITimedEvent event)

getPreviousRequest

protected IRequest getPreviousRequest()

isBusy

protected boolean isBusy(IActivationBuffer buffer)

utility method to test the state, only works if this buffer extends IStatusBuffer

Parameters:

buffer -

Returns:

setBusy

protected void setBusy(IActivationBuffer buffer)

utility method, only works if buffer extends AbstractActivationBuffer6

Parameters:

buffer -

setFree

protected void setFree(IActivationBuffer buffer)

utility method, only works if buffer extends AbstractActivationBuffer6

Parameters:

buffer -

setError

protected void setError(IActivationBuffer buffer)

utility method, only works if buffer extends AbstractActivationBuffer6

Parameters:

buffer -

setError

protected void setError(IActivationBuffer buffer,
                        IChunk errorCode)