javax.realtime

Class FirstInFirstOutReleaseRunner

java.lang.Object

javax.realtime.ReleaseRunner

javax.realtime.FirstInFirstOutReleaseRunner

public class FirstInFirstOutReleaseRunner
extends ReleaseRunner

The default ReleaseRunner that uses a pool of FIFO scheduled realtime threads to run handlers. This reduces the amount of threads required for handling events compared with bounding a thread to each handler. It also supports handlers that suspend themselves, e.g., by calling the Object.wait() method. The size of the pool of threads is based on the number of handlers, the number of priorities in use, and the number of cpus available. For systems with many AsyncBaseEventHandler instances, there can be significantly fewer threads to run releases of those handlers in the system.

Since:

RTSJ 2.0

Constructor Summary

Constructors

Constructor and Description
FirstInFirstOutReleaseRunner(ConfigurationParameters config) Same as FirstInFirstOutReleaseRunner(ConfigurationParameters, RealtimeThreadGroup, IntBinaryOperator) with arguments {(null, null, null)}.
FirstInFirstOutReleaseRunner(ConfigurationParameters config, RealtimeThreadGroup group, IntBinaryOperator sizer) Create a release runner which maintains a pool of threads to run releases of AsyncBaseEventHandler instances.

Method Summary

Modifier and Type	Method and Description
protected void	attach(Schedulable handler) Attach a handler from this runner, so it will be released.
protected void	detach(Schedulable handler) Detach a handler from this runner, so it will no longer be released.
ConfigurationParameters	getConfigurationParameters() Get the ConfigurationParameters object used for all threads provided by this release runner.
protected void	release(Schedulable handler) Finds a thread and has it call the Runnable.run() method.

Methods inherited from class javax.realtime.ReleaseRunner

getRealtimeThreadGroup

Methods inherited from class java.lang.Object

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

Constructor Detail

FirstInFirstOutReleaseRunner

public FirstInFirstOutReleaseRunner(ConfigurationParameters config,
                                    RealtimeThreadGroup group,
                                    IntBinaryOperator sizer)

Create a release runner which maintains a pool of threads to run releases of AsyncBaseEventHandler instances. The threads in the pool all run in a given RealtimeThreadGroup instance. The thread pool size is determined by the binary function sizer. When sizer is null, a reasonable default is provided.

Parameters:

config - the ConfigurationParameters object to use for all handler run from this pool, which means for each thread in the pool.

group - The realtime thread group for the pool threads.

sizer - A binary function from the number of handlers and the number of priorities of those handles to the number of threads in the pool. It may use global information, such as the number of available CPUs. It may also ignore its arguments. The calculation should be simple, since this is called often.

FirstInFirstOutReleaseRunner

public FirstInFirstOutReleaseRunner(ConfigurationParameters config)

Same as FirstInFirstOutReleaseRunner(ConfigurationParameters, RealtimeThreadGroup, IntBinaryOperator) with arguments {(null, null, null)}.

Method Detail

getConfigurationParameters

public ConfigurationParameters getConfigurationParameters()

Description copied from class: ReleaseRunner

Get the ConfigurationParameters object used for all threads provided by this release runner.

Specified by:

getConfigurationParameters in class ReleaseRunner

Returns:

those parameters.

release

protected final void release(Schedulable handler)

Description copied from class: ReleaseRunner

Finds a thread and has it call the Runnable.run() method. Care should be exercised when implementing this method, since it adds to both the latency and jitter of releasing events.

This method should only be called from the infrastructure.

Specified by:

release in class ReleaseRunner

Parameters:

handler - The handler to be released.

attach

protected void attach(Schedulable handler)
               throws StaticIllegalStateException

Attach a handler from this runner, so it will be released. Adjusts the number of threads for running handlers accordingly.

Specified by:

attach in class ReleaseRunner

Throws:

StaticIllegalStateException - when handler is already attached.

Parameters:

handler - to be removed.

detach

protected void detach(Schedulable handler)
               throws StaticIllegalStateException

Detach a handler from this runner, so it will no longer be released. Adjusts the number of threads for running handlers accordingly.

Specified by:

detach in class ReleaseRunner

Throws:

StaticIllegalStateException - when handler is not attached.

Parameters:

handler - to be detached.