javax.realtime
Class BoundAsyncEventHandler

java.lang.Object
  javax.realtime.AsyncEventHandler
      javax.realtime.BoundAsyncEventHandler

All Implemented Interfaces:

Runnable, Schedulable

public class BoundAsyncEventHandler

extends AsyncEventHandler

A bound asynchronous event handler is an asynchronous event handler that is permanently bound to a thread. Bound asynchronous event handlers are meant for use in situations where the added timeliness is worth the overhead of binding the handler to a thread.

Author:

Angelo Corsaro

Field Summary

protected boolean	active
protected Runnable	logic
protected RealtimeThread	thread

Fields inherited from class javax.realtime.AsyncEventHandler

executionEligibility, natFireCount_

Constructor Summary

BoundAsyncEventHandler()
Creates a new BoundAsyncEventHandler instance whose SchedulingParameters are inherited from the current thread and does not have either ReleaseParameters or MemoryParameters.

BoundAsyncEventHandler(boolean noHeap)
Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread ,or null other wise.

BoundAsyncEventHandler(boolean noHeap, Runnable logic)
Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread, or null otherwise.

BoundAsyncEventHandler(Runnable logic)
Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread, or null otherwise.

BoundAsyncEventHandler(SchedulingParameters schedulingParam, ReleaseParameters releaseParam, MemoryParameters memoryParam, MemoryArea memoryArea, ProcessingGroupParameters groupParam, boolean noHeap)
Creates a new BoundAsyncEventHandler instance with the specified parameters.

BoundAsyncEventHandler(SchedulingParameters schedulingParam, ReleaseParameters releaseParam, MemoryParameters memoryParam, MemoryArea memoryArea, ProcessingGroupParameters groupParam, boolean noHeap, Runnable logic)
Creates a new BoundAsyncEventHandler instance with the specified parameters.

BoundAsyncEventHandler(SchedulingParameters schedulingParam, ReleaseParameters releaseParam, MemoryParameters memoryParam, MemoryArea memoryArea, ProcessingGroupParameters groupParam, Runnable logic)
Creates a new BoundAsyncEventHandler instance with the specified parameters.

Method Summary

void	activate() This method is provided to give more control over the time at which the thread bound with this AsyncEventHandler is started.
boolean	addIfFeasible() Add to the feasibility of the already set scheduler if the resulting feasibility set is schedulable.
boolean	addToFeasibility() Inform the scheduler and cooperating facilities that the resource demands (as expressed in the associated instances of SchedulingParameters, ReleaseParameters, MemoryParameters, and ProcessingGroupParameters) of this instance of Schedulable will be considered in the feasibility analysis of the associated Scheduler until further notice.
void	deactivate()
int	executionEligibility() NOTE: This method is not part of the RTSJ Specification.
MemoryParameters	getMemoryParameters() Get the MemoryParameters of this schedulable object.
ProcessingGroupParameters	getProcessingGroupParameters() Get the ProcessingGroupParameters of this schedulable object.
ReleaseParameters	getReleaseParameters() Get the ReleaseParameters of this schedulable object.
Scheduler	getScheduler() Get the Scheduler for this schedulable object.
SchedulingParameters	getSchedulingParameters() Get the SchedulingParameters for this schedulable object.
void	handleAsyncEvent() If this handler was constructed using a separate Runnable logic object, then that Runnable object s run method is called; This method will be invoked repeatedly while fireCount is greater than zero.
protected void	handleAsyncEventImpl()
boolean	removeFromFeasibility() Inform the scheduler and cooperating facilities that the resource demands, as expressed in the associated instances of SchedulingParameters, ReleaseParameters, MemoryParameters, and ProcessingGroupParameters, of this instance of Schedulable should no longer be considered in the feasibility analysis of the associated Scheduler.
void	setMemoryParameters(MemoryParameters memoryParam) Set the MemoryParameters for this schedulable object.
boolean	setMemoryParametersIfFeasible(MemoryParameters memoryParam) Returns true if, after considering the value of the parameter, the task set would still be feasible.
void	setProcessingGroupParameters(ProcessingGroupParameters groupParam) Set the ProcessingGroupParameters for this schedulable object.
boolean	setProcessingGroupParametersIfFeasible(ProcessingGroupParameters groupParam) Set the ProcessingGroupParameters of this schedulable object only if the resulting task set is feasible.
void	setReleaseParameters(ReleaseParameters releaseParam) Set the ReleaseParametersfor this schedulable object.
boolean	setReleaseParametersIfFeasible(ReleaseParameters releaseParam) Returns true if, after considering the value of the parameter, the task set would still be feasible.
void	setScheduler(Scheduler scheduler) Set the Scheduler for this schedulable object.
void	setScheduler(Scheduler scheduler, SchedulingParameters schedulingParam, ReleaseParameters releaseParam, MemoryParameters memoryParam, ProcessingGroupParameters groupParam) Set the Scheduler for this schedulable object.
void	setSchedulingParameters(SchedulingParameters schedulingParam) Set the SchedulingParameters for this schedulable object only if the resulting task set is feasible.
boolean	setSchedulingParametersIfFeasible(SchedulingParameters schedulingParam) Set the SchedulingParameters for this schedulable object.

Methods inherited from class javax.realtime.AsyncEventHandler

finalize, getAndClearPendingFireCount, getAndDecrementPendingFireCount, getAndIncrementPendingFireCount, getPendingFireCount, run

Methods inherited from class java.lang.Object

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

Field Detail

thread

protected RealtimeThread thread

active

protected boolean active

logic

protected Runnable logic

Constructor Detail

BoundAsyncEventHandler

public BoundAsyncEventHandler()

Creates a new BoundAsyncEventHandler instance whose SchedulingParameters are inherited from the current thread and does not have either ReleaseParameters or MemoryParameters.

BoundAsyncEventHandler

public BoundAsyncEventHandler(boolean noHeap)

Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread ,or null other wise.

Parameters:

noHeap - A flag meaning, when true, that this will have characteristics identical to a NoHeapRealtimeThread. A false value means this will have characteristics identical to a RealtimeThread. If true and the current thread is not a NoHeapRealtimeThread or a RealtimeThread executing within a ScopedMemory or ImmortalMemory scope then an IllegalArgumentException is thrown.

BoundAsyncEventHandler

public BoundAsyncEventHandler(Runnable logic)

Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread, or null otherwise.

Parameters:

logic - The java.lang.Runnable object whose run is executed by handleAsyncEvent.

BoundAsyncEventHandler

public BoundAsyncEventHandler(boolean noHeap,
                              Runnable logic)
                       throws IllegalArgumentException

Creates a new BoundAsyncEventHandler instance whose parameters are inherited from the current thread, if it is a RealtimeThread, or null otherwise.

Parameters:

noHeap - A flag meaning, when true, that this will have characteristics identical to a NoHeapRealtimeThread. A false value means this will have characteristics identical to a RealtimeThread. If true and the current thread is not a NoHeapRealtimeThread or a RealtimeThread executing within a ScopedMemory or ImmortalMemory scope then an IllegalArgumentException is thrown.

logic - -The java.lang.Runnable object whose run is executed by handleAsyncEvent.

Throws:

IllegalArgumentException

BoundAsyncEventHandler

public BoundAsyncEventHandler(SchedulingParameters schedulingParam,
                              ReleaseParameters releaseParam,
                              MemoryParameters memoryParam,
                              MemoryArea memoryArea,
                              ProcessingGroupParameters groupParam,
                              boolean noHeap)
                       throws IllegalArgumentException

Creates a new BoundAsyncEventHandler instance with the specified parameters.

Parameters:

schedulingParam - a SchedulingParameters value which will be associated with the constructed instance of this. If null this will be assigned the reference to the SchedulingParameters of the current thread.

releaseParam - a ReleaseParameters value which will be associated with the constructed instance of this. If null this will have no ReleaseParameters.

memoryParam - a MemoryParameters value which will be associated with the constructed instance of this. If null this will have no MemoryParameters.

memoryArea - The MemoryArea for this BoundAsyncEventHandler. If null, inherit the current memory area at the time of construction. The initial memory area must be a reference to a ScopedMemory or ImmortalMemory object if noheap is true.

groupParam - A ProcessingGroupParameters object to which this will be associated. If null this will not be associated with any processing group.

noHeap - A flag meaning, when true, that this will have characteristics identical to a NoHeapRealtimeThread. A false value means this will have characteristics identical to a RealtimeThread. If true and the current thread is not a NoHeapRealtimeThread or a RealtimeThread executing within a ScopedMemory or ImmortalMemory scope then an IllegalArgumentException is thrown.

Throws:

IllegalArgumentException

BoundAsyncEventHandler

public BoundAsyncEventHandler(SchedulingParameters schedulingParam,
                              ReleaseParameters releaseParam,
                              MemoryParameters memoryParam,
                              MemoryArea memoryArea,
                              ProcessingGroupParameters groupParam,
                              Runnable logic)
                       throws IllegalArgumentException

Creates a new BoundAsyncEventHandler instance with the specified parameters.

Parameters:

schedulingParam - a SchedulingParameters value which will be associated with the constructed instance of this. If null this will be assigned the reference to the SchedulingParameters of the current thread.

releaseParam - a ReleaseParameters value which will be associated with the constructed instance of this. If null this will have no ReleaseParameters.

memoryParam - a MemoryParameters value which will be associated with the constructed instance of this. If null this will have no MemoryParameters.

memoryArea - The MemoryArea for this BoundAsyncEventHandler. If null, inherit the current memory area at the time of construction. The initial memory area must be a reference to a ScopedMemory or ImmortalMemory object if noheap is true.

groupParam - A ProcessingGroupParameters object to which this will be associated. If null this will not be associated with any processing group.

logic - The java.lang.Runnable object whose run is executed by handleAsyncEvent.

Throws:

IllegalArgumentException

BoundAsyncEventHandler

public BoundAsyncEventHandler(SchedulingParameters schedulingParam,
                              ReleaseParameters releaseParam,
                              MemoryParameters memoryParam,
                              MemoryArea memoryArea,
                              ProcessingGroupParameters groupParam,
                              boolean noHeap,
                              Runnable logic)
                       throws IllegalArgumentException

Creates a new BoundAsyncEventHandler instance with the specified parameters.

Parameters:

schedulingParam - a SchedulingParameters value which will be associated with the constructed instance of this. If null this will be assigned the reference to the SchedulingParameters of the current thread.

releaseParam - a ReleaseParameters value which will be associated with the constructed instance of this. If null this will have no ReleaseParameters.

memoryParam - a MemoryParameters value which will be associated with the constructed instance of this. If null this will have no MemoryParameters.

memoryArea - The MemoryArea for this BoundAsyncEventHandler. If null, inherit the current memory area at the time of construction. The initial memory area must be a reference to a ScopedMemory or ImmortalMemory object if noheap is true.

groupParam - A ProcessingGroupParameters object to which this will be associated. If null this will not be associated with any processing group.

noHeap - A flag meaning, when true, that this will have characteristics identical to a NoHeapRealtimeThread. A false value means this will have characteristics identical to a RealtimeThread. If true and the current thread is not a NoHeapRealtimeThread or a RealtimeThread executing within a ScopedMemory or ImmortalMemory scope then an IllegalArgumentException is thrown.

logic - The java.lang.Runnable object whose run is executed by handleAsyncEvent.

Throws:

IllegalArgumentException

Method Detail

handleAsyncEvent

public void handleAsyncEvent()

If this handler was constructed using a separate Runnable logic object, then that Runnable object s run method is called; This method will be invoked repeatedly while fireCount is greater than zero.

Specified by:

handleAsyncEvent in class AsyncEventHandler

handleAsyncEventImpl

protected void handleAsyncEventImpl()

activate

public void activate()

This method is provided to give more control over the time at which the thread bound with this AsyncEventHandler is started. If this method is not invoked to explicitly start the dispatch thread, it will then be started upon arrival of the first event.

deactivate

public void deactivate()

addIfFeasible

public boolean addIfFeasible()

Add to the feasibility of the already set scheduler if the resulting feasibility set is schedulable. If successful return true, if not return false. If there is not an assigned scheduler it will return false.

Returns:

If successful return true, if not return false. If there is not an assigned scheduler it will return false.

addToFeasibility

public boolean addToFeasibility()

Inform the scheduler and cooperating facilities that the resource demands (as expressed in the associated instances of SchedulingParameters, ReleaseParameters, MemoryParameters, and ProcessingGroupParameters) of this instance of Schedulable will be considered in the feasibility analysis of the associated Scheduler until further notice. Whether the resulting system is feasible or not, the addition is completed.

Returns:

true If the resulting system is feasible.

getMemoryParameters

public MemoryParameters getMemoryParameters()

Get the MemoryParameters of this schedulable object.

Returns:

a MemoryParameters value.

setMemoryParameters

public void setMemoryParameters(MemoryParameters memoryParam)

Set the MemoryParameters for this schedulable object.

Parameters:

memoryParam - the MemoryParameters for this schedulable object.

setMemoryParametersIfFeasible

public boolean setMemoryParametersIfFeasible(MemoryParameters memoryParam)

Returns true if, after considering the value of the parameter, the task set would still be feasible. In this case the values of the parameters are changed. Returns false if, after considering the value of the parameter, the task set would not be feasible. In this case the values of the parameters are not changed.

Parameters:

memoryParam - the MemoryParameters for this schedulable object.

Returns:

true if the requested change keeps the system feasible.

getProcessingGroupParameters

public ProcessingGroupParameters getProcessingGroupParameters()

Get the ProcessingGroupParameters of this schedulable object.

Returns:

a ProcessingGroupParameters value

setProcessingGroupParameters

public void setProcessingGroupParameters(ProcessingGroupParameters groupParam)

Set the ProcessingGroupParameters for this schedulable object.

Parameters:

groupParam - a ProcessingGroupParameters value

setProcessingGroupParametersIfFeasible

public boolean setProcessingGroupParametersIfFeasible(ProcessingGroupParameters groupParam)

Set the ProcessingGroupParameters of this schedulable object only if the resulting task set is feasible.

Parameters:

groupParam - a ProcessingGroupParameters value

Returns:

Returns true if, after considering the values of the parameters, the task set would still be feasible. In this case the values of the parameters are changed. Returns false if, after considering the values of the parameters, the task set would not be feasible. In this case the values of the parameters are not changed.

getReleaseParameters

public ReleaseParameters getReleaseParameters()

Get the ReleaseParameters of this schedulable object.

Returns:

a ReleaseParameters value

setReleaseParameters

public void setReleaseParameters(ReleaseParameters releaseParam)

Set the ReleaseParametersfor this schedulable object.

Parameters:

releaseParam - a ReleaseParameters value

setReleaseParametersIfFeasible

public boolean setReleaseParametersIfFeasible(ReleaseParameters releaseParam)

Returns true if, after considering the value of the parameter, the task set would still be feasible. In this case the values of the parameters are changed. Returns false if, after considering the value of the parameter, the task set would not be feasible. In this case the values of the parameters are not changed. the resulting task set is feasible.

Parameters:

releaseParam - a ReleaseParameters value

getScheduler

public Scheduler getScheduler()

Get the Scheduler for this schedulable object.

Returns:

a Scheduler value

setScheduler

public void setScheduler(Scheduler scheduler)
                  throws IllegalThreadStateException

Set the Scheduler for this schedulable object.

Parameters:

scheduler - the scheduler.

Throws:

IllegalThreadStateException

setScheduler

public void setScheduler(Scheduler scheduler,
                         SchedulingParameters schedulingParam,
                         ReleaseParameters releaseParam,
                         MemoryParameters memoryParam,
                         ProcessingGroupParameters groupParam)
                  throws IllegalThreadStateException

Set the Scheduler for this schedulable object.

Parameters:

scheduler - a Scheduler value

schedulingParam - a SchedulingParameters value

releaseParam - a ReleaseParameters value

memoryParam - a MemoryParameters value

groupParam - a ProcessingGroupParameters value

Throws:

IllegalThreadStateException - if an error occurs

getSchedulingParameters

public SchedulingParameters getSchedulingParameters()

Get the SchedulingParameters for this schedulable object.

Returns:

a SchedulingParameters value

setSchedulingParameters

public void setSchedulingParameters(SchedulingParameters schedulingParam)

Set the SchedulingParameters for this schedulable object only if the resulting task set is feasible.

Parameters:

schedulingParam - a SchedulingParameters value

setSchedulingParametersIfFeasible

public boolean setSchedulingParametersIfFeasible(SchedulingParameters schedulingParam)

Set the SchedulingParameters for this schedulable object.

Parameters:

schedulingParam - a SchedulingParameters value

Returns:

true if the change was feasible, false otherwise.

removeFromFeasibility

public boolean removeFromFeasibility()

Inform the scheduler and cooperating facilities that the resource demands, as expressed in the associated instances of SchedulingParameters, ReleaseParameters, MemoryParameters, and ProcessingGroupParameters, of this instance of Schedulable should no longer be considered in the feasibility analysis of the associated Scheduler. Whether the resulting system is feasible or not, the subtrac-tion is completed.

Returns:

true If the resulting system is feasible.

executionEligibility

public int executionEligibility()

Description copied from interface: Schedulable

NOTE: This method is not part of the RTSJ Specification. It is used internally by this RTSJ implementation.

Returns:

an int value used internally to represent a total ordering of the schedulable entities.