Package org.apache.hadoop.util

Class BlockingThreadPoolExecutorService

java.lang.Object

org.apache.hadoop.thirdparty.com.google.common.collect.ForwardingObject

org.apache.hadoop.thirdparty.com.google.common.util.concurrent.ForwardingExecutorService

org.apache.hadoop.util.SemaphoredDelegatingExecutor

org.apache.hadoop.util.BlockingThreadPoolExecutorService

All Implemented Interfaces:

Executor, ExecutorService

@Private
public final class BlockingThreadPoolExecutorService
extends SemaphoredDelegatingExecutor

This ExecutorService blocks the submission of new tasks when its queue is already full by using a semaphore. Task submissions require permits, task completions release permits.

This is inspired by this s4 threadpool

Method Summary

Modifier and Type	Method	Description
static ThreadFactory	newDaemonThreadFactory(String prefix)	Get a named ThreadFactory that just builds daemon threads.
static BlockingThreadPoolExecutorService	newInstance(int activeTasks, int waitingTasks, long keepAliveTime, TimeUnit unit, String prefixName)	A thread pool that that blocks clients submitting additional tasks if there are already activeTasks running threads and waitingTasks tasks waiting in its queue.
String	toString()

Methods inherited from class org.apache.hadoop.util.SemaphoredDelegatingExecutor

delegate, execute, getAvailablePermits, getPermitCount, getWaitingCount, invokeAll, invokeAll, invokeAny, invokeAny, submit, submit, submit

Methods inherited from class org.apache.hadoop.thirdparty.com.google.common.util.concurrent.ForwardingExecutorService

awaitTermination, isShutdown, isTerminated, shutdown, shutdownNow

Methods inherited from class java.lang.Object

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

Method Details

newDaemonThreadFactory

public static ThreadFactory newDaemonThreadFactory(String prefix)

Get a named ThreadFactory that just builds daemon threads.

Parameters:

prefix - name prefix for all threads created from the factory

Returns:

a thread factory that creates named, daemon threads with the supplied exception handler and normal priority

newInstance

public static BlockingThreadPoolExecutorService newInstance(int activeTasks,
 int waitingTasks,
 long keepAliveTime,
 TimeUnit unit,
 String prefixName)

A thread pool that that blocks clients submitting additional tasks if there are already activeTasks running threads and waitingTasks tasks waiting in its queue.

Parameters:

activeTasks - maximum number of active tasks

waitingTasks - maximum number of waiting tasks

keepAliveTime - time until threads are cleaned up in unit

unit - time unit

prefixName - prefix of name for threads

Returns:

BlockingThreadPoolExecutorService.

toString

public String toString()

Overrides:

toString in class SemaphoredDelegatingExecutor