com.hp.util.concurrent

Class ThreadMonitor

java.lang.Object

com.hp.util.concurrent.ThreadMonitor

All Implemented Interfaces:

CallableExecutor, RunnableExecutor, ThreadExecutor

public class ThreadMonitor
extends Object
implements ThreadExecutor

ThreadExecutor proxy used to track threads. Its purpose is to be used for debugging at development phase, it should not be used at production code.

Author:

Scott Simes, Fabiel Zuniga

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ThreadMonitor.ThreadExecutionState Thread execution state.
static interface	ThreadMonitor.ThreadListener Thread listener.

Constructor Summary

Constructors

Constructor and Description
ThreadMonitor(ThreadExecutor delegate, ThreadMonitor.ThreadListener threadListener, javax.measure.Measurable<javax.measure.quantity.Duration> activeThreadsStateUpdateFrequency) Creates a new thread monitor.

Method Summary

Methods

Modifier and Type	Method and Description
<T> ScheduledFuture<T>	schedule(Callable<T> task, javax.measure.Measurable<javax.measure.quantity.Duration> delay) Creates and executes a ScheduledFuture that becomes enabled after the given delay.
ScheduledFuture<?>	schedule(Runnable task, javax.measure.Measurable<javax.measure.quantity.Duration> delay) Creates and executes a ScheduledFuture that becomes enabled after the given delay.
ScheduledFuture<?>	scheduleAtFixedRate(Runnable task, Date initialTime, javax.measure.Measurable<javax.measure.quantity.Duration> period) For the sake of cancellability but not provide a usable result Creates and executes a periodic action that becomes enabled first at the given initial time, and subsequently with the given period; that is executions will commence at initialTime then initialTime+period, then initialTime + 2 * period, and so on.
ScheduledFuture<?>	scheduleAtFixedRate(Runnable task, javax.measure.Measurable<javax.measure.quantity.Duration> initialDelay, javax.measure.Measurable<javax.measure.quantity.Duration> period) Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given period; that is executions will commence after initialDelay then initialDelay+period, then initialDelay + 2 * period, and so on.
ScheduledFuture<?>	scheduleWithFixedDelay(Runnable task, javax.measure.Measurable<javax.measure.quantity.Duration> initialDelay, javax.measure.Measurable<javax.measure.quantity.Duration> delay) Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next.
<T> Future<T>	submit(Callable<T> task) This method is used to decouple execution of task i.e.
Future<?>	submit(Runnable task) This method is use to decouple execution of task i.e.

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadMonitor

public ThreadMonitor(ThreadExecutor delegate,
             ThreadMonitor.ThreadListener threadListener,
             javax.measure.Measurable<javax.measure.quantity.Duration> activeThreadsStateUpdateFrequency)

Creates a new thread monitor.

Parameters:

delegate - delegate

threadListener - listener to handle thread monitoring, see LoggerThreadListener

activeThreadsStateUpdateFrequency - frequency to update active threads state, null to not track active threads state at all. If null is used the executing() method in ThreadListener won't be called.

Method Detail

submit

public Future<?> submit(Runnable task)

Description copied from interface: RunnableExecutor

This method is use to decouple execution of task i.e. to have a task executed in the context of a worker thread instead of in the context of the calling thread.

Specified by:

submit in interface RunnableExecutor

Parameters:

task - task to be executed

Returns:

a Future instance related to the result of the execution of the task.

submit

public <T> Future<T> submit(Callable<T> task)

Description copied from interface: CallableExecutor

This method is used to decouple execution of task i.e. to have a task executed in the context of a worker thread instead of in the context of the calling thread.

Specified by:

submit in interface CallableExecutor

Type Parameters:

T - type of the execution result

Parameters:

task - task to be executed

Returns:

a Future instance related to the result of the execution of the task. Result can be retrieved via get method.

schedule

public ScheduledFuture<?> schedule(Runnable task,
                          javax.measure.Measurable<javax.measure.quantity.Duration> delay)

Description copied from interface: ThreadExecutor

Creates and executes a ScheduledFuture that becomes enabled after the given delay.

Specified by:

schedule in interface ThreadExecutor

Parameters:

task - the runnable task to be executed

delay - the time from now to delay execution

Returns:

a future that can be used to cancel

schedule

public <T> ScheduledFuture<T> schedule(Callable<T> task,
                              javax.measure.Measurable<javax.measure.quantity.Duration> delay)

Description copied from interface: ThreadExecutor

Creates and executes a ScheduledFuture that becomes enabled after the given delay.

Specified by:

schedule in interface ThreadExecutor

Type Parameters:

T - the type of the execution result

Parameters:

task - the task to be executed

delay - the time from now to delay execution

Returns:

a future that can be used to extract result or cancel

scheduleAtFixedRate

public ScheduledFuture<?> scheduleAtFixedRate(Runnable task,
                                     javax.measure.Measurable<javax.measure.quantity.Duration> initialDelay,
                                     javax.measure.Measurable<javax.measure.quantity.Duration> period)

Description copied from interface: ThreadExecutor

Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given period; that is executions will commence after initialDelay then initialDelay+period, then initialDelay + 2 * period, and so on.

Specified by:

scheduleAtFixedRate in interface ThreadExecutor

Parameters:

task - the task to be executed

initialDelay - the time to delay first execution

period - the period between successive executions

Returns:

a future representing pending completion of the task, and whose get() method will throw an exception upon cancellation

scheduleAtFixedRate

public ScheduledFuture<?> scheduleAtFixedRate(Runnable task,
                                     Date initialTime,
                                     javax.measure.Measurable<javax.measure.quantity.Duration> period)
                                       throws IllegalArgumentException

Description copied from interface: ThreadExecutor

For the sake of cancellability but not provide a usable result Creates and executes a periodic action that becomes enabled first at the given initial time, and subsequently with the given period; that is executions will commence at initialTime then initialTime+period, then initialTime + 2 * period, and so on.

Specified by:

scheduleAtFixedRate in interface ThreadExecutor

Parameters:

task - the task to be executed

initialTime - the time of the first execution

period - the period between successive executions

Returns:

a future representing pending completion of the task, and whose get() method will throw an exception upon cancellation

Throws:

IllegalArgumentException - if initialTime is in the past

scheduleWithFixedDelay

public ScheduledFuture<?> scheduleWithFixedDelay(Runnable task,
                                        javax.measure.Measurable<javax.measure.quantity.Duration> initialDelay,
                                        javax.measure.Measurable<javax.measure.quantity.Duration> delay)

Description copied from interface: ThreadExecutor

Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next.

Specified by:

scheduleWithFixedDelay in interface ThreadExecutor

Parameters:

task - the task to be executed

initialDelay - the time to delay first execution.

delay - the delay between the termination of one execution and the commencement of the next

Returns:

a future representing pending completion of the task, and whose get() method will throw an exception upon cancellation