Package org.glassfish.jersey.spi

Class ThreadPoolExecutorProvider

java.lang.Object

org.glassfish.jersey.spi.AbstractThreadPoolProvider<ThreadPoolExecutor>

org.glassfish.jersey.spi.ThreadPoolExecutorProvider

All Implemented Interfaces:

AutoCloseable, ExecutorServiceProvider

public class ThreadPoolExecutorProvider
extends AbstractThreadPoolProvider<ThreadPoolExecutor>
implements ExecutorServiceProvider

Default implementation of the Jersey executor service provider SPI.

This provider creates and provisions a shared ThreadPoolExecutor instance using the customizable values for :

• number of core pool threads
• maximum number of threads in the pool
• thread keep-alive time (in seconds)
• backing thread pool work queue
• backing thread factory
• rejected task handler

Subclasses may override the respective methods to customize the parameters of the provisioned thread pool executor.

Since:

2.18

Author:

Marek Potociar

Field Summary

Fields inherited from class org.glassfish.jersey.spi.AbstractThreadPoolProvider

DEFAULT_TERMINATION_TIMEOUT

Constructor Summary

Constructors

Constructor	Description
ThreadPoolExecutorProvider(String name)	Create a new instance of the thread pool executor provider.

Method Summary

Modifier and Type	Method	Description
protected ThreadPoolExecutor	createExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, BlockingQueue<Runnable> workQueue, ThreadFactory threadFactory, RejectedExecutionHandler handler)	Creates a new ThreadPoolExecutor with the given initial parameters.
protected ThreadPoolExecutor	createExecutor(int corePoolSize, ThreadFactory threadFactory, RejectedExecutionHandler handler)	Create a new instance of the thread pool executor that should be provided by the AbstractThreadPoolProvider.getExecutor() method.
void	dispose(ExecutorService executorService)	Invoked when Jersey runtime no longer requires use of the provided executor service.
ExecutorService	getExecutorService()	Get an executor service to be used by Jersey client or server runtime to execute specific tasks.
protected long	getKeepAliveTime()	Get the thread keep-alive time (in seconds).
protected int	getMaximumPoolSize()	Get the maximum number of threads to allow in the thread pool.
protected BlockingQueue<Runnable>	getWorkQueue()	Get the work queue for the provisioned thread pool executor.
void	preDestroy()	Container pre-destroy handler method.

Methods inherited from class org.glassfish.jersey.spi.AbstractThreadPoolProvider

close, getBackingThreadFactory, getCorePoolSize, getExecutor, getRejectedExecutionHandler, getTerminationTimeout, isClosed, onClose

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadPoolExecutorProvider

public ThreadPoolExecutorProvider(String name)

Create a new instance of the thread pool executor provider.

Parameters:

name - provider name. The name will be used to name the threads created & used by the provisioned thread pool executor.

Method Detail

getExecutorService

public ExecutorService getExecutorService()

Description copied from interface: ExecutorServiceProvider

Get an executor service to be used by Jersey client or server runtime to execute specific tasks.

This method is usually invoked just once at either Jersey client or server application runtime initialization, it may however be invoked multiple times. Once the instance of the provided executor service is not needed anymore by Jersey application runtime, it will be disposed. This typically happens in one of the following situations:

• Jersey client instance is closed (client runtime is shut down).
• Jersey container running a server-side Jersey application is shut down.
• Jersey server-side application is un-deployed.

Specified by:

getExecutorService in interface ExecutorServiceProvider

Returns:

an executor service. Must not return null.

createExecutor

protected final ThreadPoolExecutor createExecutor(int corePoolSize,
                                                  ThreadFactory threadFactory,
                                                  RejectedExecutionHandler handler)

Description copied from class: AbstractThreadPoolProvider

Create a new instance of the thread pool executor that should be provided by the AbstractThreadPoolProvider.getExecutor() method.

Concrete implementations of this class must override this method and implement the logic that creates the executor service to be provided. The returned thread pool executor will be shut down when this provider instance is closed.

This method is invoked at most once, during the first call to the getExecutor() method.

Specified by:

createExecutor in class AbstractThreadPoolProvider<ThreadPoolExecutor>

Parameters:

corePoolSize - number of core threads the provisioned thread pool executor should provide.

threadFactory - thread factory to be used by the provisioned thread pool executor when creating new threads.

handler - handler for tasks that cannot be executed by the provisioned thread pool executor (e.g. due to a shutdown).

Returns:

new instance of the provided thread pool executor.

See Also:

AbstractThreadPoolProvider.getExecutor(), AbstractThreadPoolProvider.close(), AbstractThreadPoolProvider.getCorePoolSize(), AbstractThreadPoolProvider.getBackingThreadFactory(), AbstractThreadPoolProvider.getRejectedExecutionHandler()

createExecutor

protected ThreadPoolExecutor createExecutor(int corePoolSize,
                                            int maximumPoolSize,
                                            long keepAliveTime,
                                            BlockingQueue<Runnable> workQueue,
                                            ThreadFactory threadFactory,
                                            RejectedExecutionHandler handler)

Creates a new ThreadPoolExecutor with the given initial parameters.

Parameters:

corePoolSize - the number of threads to keep in the thread pool, even if they are idle.

maximumPoolSize - the maximum number of threads to allow in the thread pool.

keepAliveTime - when the number of threads is greater than the core, this is the maximum time (in seconds) that excess idle threads will wait for new tasks before terminating.

workQueue - the queue to use for holding tasks before they are executed. This queue will hold only the Runnable tasks submitted by the execute method.

threadFactory - the factory to use when the executor creates a new thread.

handler - the handler to use when execution is blocked because the thread bounds and queue capacities are reached.

Returns:

new configured thread pool instance.

Throws:

IllegalArgumentException - if one of the following holds:
corePoolSize < 0
keepAliveTime < 0
maximumPoolSize <= 0
maximumPoolSize < corePoolSize

NullPointerException - if workQueue or threadFactory or handler is null.

getMaximumPoolSize

protected int getMaximumPoolSize()

Get the maximum number of threads to allow in the thread pool.

The value from this method is passed as one of the input parameters in a call to the createExecutor(int, int, long, java.util.concurrent.BlockingQueue, java.util.concurrent.ThreadFactory, java.util.concurrent.RejectedExecutionHandler) method.

The method can be overridden to customize the maximum number of threads allowed in the provisioned thread pool executor. If not customized, the method defaults to Integer.MAX_VALUE.

Returns:

maximum number of threads allowed in the thread pool.

getKeepAliveTime

protected long getKeepAliveTime()

Get the thread keep-alive time (in seconds).

When the number of threads in the provisioned thread pool is greater than the core, this is the maximum time (in seconds) that excess idle threads will wait for new tasks before terminating.

The value from this method is passed as one of the input parameters in a call to the createExecutor(int, int, long, java.util.concurrent.BlockingQueue, java.util.concurrent.ThreadFactory, java.util.concurrent.RejectedExecutionHandler) method.

The method can be overridden to customize the thread keep-alive time in the provisioned thread pool executor. If not customized, the method defaults to:

• 60L in case the maximum pool size is equal to Integer.MAX_VALUE
• 0L in case the maximum pool size is lower than java.lang.Integer#MAX_VALUE

The default value computation closely corresponds to the thread pool executor configurations used in Executors.newCachedThreadPool() and Executors.newFixedThreadPool(int) methods.

Returns:

thread keep-alive time (in seconds) for the provisioned thread pool executor.

getWorkQueue

protected BlockingQueue<Runnable> getWorkQueue()

Get the work queue for the provisioned thread pool executor.

The work queue is used to hold the tasks before they are executed by the provisioned thread pool executor. The queue will hold only the Runnable tasks submitted by the ThreadPoolExecutor.execute(java.lang.Runnable) method.

The value from this method is passed as one of the input parameters in a call to the createExecutor(int, int, long, java.util.concurrent.BlockingQueue, java.util.concurrent.ThreadFactory, java.util.concurrent.RejectedExecutionHandler) method.

The method can be overridden to customize the work queue used by the provisioned thread pool executor. If not customized, the method defaults to:

• SynchronousQueue in case the maximum pool size is equal to Integer.MAX_VALUE
• LinkedBlockingQueue in case the maximum pool size is lower than java.lang.Integer#MAX_VALUE

The default value computation closely corresponds to the thread pool executor configurations used in Executors.newCachedThreadPool() and Executors.newFixedThreadPool(int) methods.

Returns:

work queue for the provisioned thread pool executor.

dispose

public void dispose(ExecutorService executorService)

Description copied from interface: ExecutorServiceProvider

Invoked when Jersey runtime no longer requires use of the provided executor service.

Specified by:

dispose in interface ExecutorServiceProvider

Parameters:

executorService - executor service to be disposed.

preDestroy

@PreDestroy
public void preDestroy()

Container pre-destroy handler method.

Invoking the method closes this provider.