Package org.apache.activemq.util

Class ThreadPoolUtils

java.lang.Object

org.apache.activemq.util.ThreadPoolUtils

public final class ThreadPoolUtils
extends Object

Utility methods for working with thread pools ExecutorService.

Field Summary

Fields

Modifier and Type	Field	Description
static long	DEFAULT_SHUTDOWN_AWAIT_TERMINATION

Constructor Summary

Constructors

Constructor	Description
ThreadPoolUtils()

Method Summary

Modifier and Type	Method	Description
static void	awaitTermination(ExecutorService executorService)	Awaits the termination of the thread pool indefinitely (Use with Caution).
static boolean	awaitTermination(ExecutorService executorService, long shutdownAwaitTermination)	Awaits the termination of the thread pool.
static void	shutdown(ExecutorService executorService)	Shutdown the given executor service only (ie not graceful shutdown).
static void	shutdownGraceful(ExecutorService executorService)	Shutdown the given executor service graceful at first, and then aggressively if the await termination timeout was hit.
static void	shutdownGraceful(ExecutorService executorService, long shutdownAwaitTermination)	Shutdown the given executor service graceful at first, and then aggressively if the await termination timeout was hit.
static List<Runnable>	shutdownNow(ExecutorService executorService)	Shutdown now the given executor service aggressively.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_SHUTDOWN_AWAIT_TERMINATION

public static final long DEFAULT_SHUTDOWN_AWAIT_TERMINATION

See Also:

Constant Field Values

Constructor Detail

ThreadPoolUtils

public ThreadPoolUtils()

Method Detail

shutdown

public static void shutdown(ExecutorService executorService)

Shutdown the given executor service only (ie not graceful shutdown).

See Also:

ExecutorService.shutdown()

shutdownNow

public static List<Runnable> shutdownNow(ExecutorService executorService)

Shutdown now the given executor service aggressively.

Parameters:

executorService - the executor service to shutdown now

Returns:

list of tasks that never commenced execution

See Also:

ExecutorService.shutdownNow()

shutdownGraceful

public static void shutdownGraceful(ExecutorService executorService)

Shutdown the given executor service graceful at first, and then aggressively if the await termination timeout was hit.

This implementation invokes the shutdownGraceful(java.util.concurrent.ExecutorService, long) with a timeout value of DEFAULT_SHUTDOWN_AWAIT_TERMINATION millis.

shutdownGraceful

public static void shutdownGraceful(ExecutorService executorService,
                                    long shutdownAwaitTermination)

Shutdown the given executor service graceful at first, and then aggressively if the await termination timeout was hit.

Will try to perform an orderly shutdown by giving the running threads time to complete tasks, before going more aggressively by doing a shutdownNow(java.util.concurrent.ExecutorService) which forces a shutdown. The parameter shutdownAwaitTermination is used as timeout value waiting for orderly shutdown to complete normally, before going aggressively. If the shutdownAwaitTermination value is negative the shutdown waits indefinitely for the ExecutorService to complete its shutdown.

Parameters:

executorService - the executor service to shutdown

shutdownAwaitTermination - timeout in millis to wait for orderly shutdown

awaitTermination

public static void awaitTermination(ExecutorService executorService)
                             throws InterruptedException

Awaits the termination of the thread pool indefinitely (Use with Caution).

This implementation will log every 2nd second at INFO level that we are waiting, so the end user can see we are not hanging in case it takes longer time to terminate the pool.

Parameters:

executorService - the thread pool

Throws:

InterruptedException - is thrown if we are interrupted during the waiting

awaitTermination

public static boolean awaitTermination(ExecutorService executorService,
                                       long shutdownAwaitTermination)
                                throws InterruptedException

Awaits the termination of the thread pool.

This implementation will log every 2nd second at INFO level that we are waiting, so the end user can see we are not hanging in case it takes longer time to terminate the pool.

Parameters:

executorService - the thread pool

shutdownAwaitTermination - time in millis to use as timeout

Returns:

true if the pool is terminated, or false if we timed out

Throws:

InterruptedException - is thrown if we are interrupted during the waiting