de.aristaflow.adept2.util.threading

Class CachedThreadPoolExecutor

java.lang.Object

java.util.concurrent.AbstractExecutorService

java.util.concurrent.ThreadPoolExecutor

de.aristaflow.adept2.util.threading.AFThreadPoolExecutor

de.aristaflow.adept2.util.threading.CachedThreadPoolExecutor

All Implemented Interfaces:

java.util.concurrent.Executor, java.util.concurrent.ExecutorService

Direct Known Subclasses:

AbstractObjectSpecificExecutor

public class CachedThreadPoolExecutor
extends AFThreadPoolExecutor

A ThreadPoolExecutor with a special behaviour:

• Creates new threads to run a new task, if the amount of threads is less than the corePoolSize. Core pool threads will be reused and will live until the thread pool is shutdown.
• Creates new threads, if the amount of threads is less than the maxPoolSize. These threads will die, if the workload reduces.
• If there is more work than the amount of maximum threads, the tasks will be put into an unbounded queue.

Author:

Ulrich Kreher

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.ThreadPoolExecutor

java.util.concurrent.ThreadPoolExecutor.AbortPolicy, java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy, java.util.concurrent.ThreadPoolExecutor.DiscardOldestPolicy, java.util.concurrent.ThreadPoolExecutor.DiscardPolicy

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.concurrent.atomic.AtomicBoolean	fullSize Whether the pool (its amount of core threads) is set to the maximum size.
protected int	realCoreSize The normal core size of the pool.
protected int	realMaxSize The maximum size of the pool.
protected java.util.concurrent.atomic.AtomicInteger	workSize The amount of work currently in the pool.

Fields inherited from class de.aristaflow.adept2.util.threading.AFThreadPoolExecutor

activeThreads, completedTasks, submittedTasks

Constructor Summary

Constructors

Constructor and Description
CachedThreadPoolExecutor(int corePoolSize, int maxPoolSize, boolean prestart, Adept2ThreadFactory threadFactory) Creates a new CachedThreadPoolExecutor with the given initial parameters and default rejected execution handler.

Method Summary

Modifier and Type	Method and Description
protected void	afterExecute(java.lang.Runnable r, java.lang.Throwable t)
void	execute(java.lang.Runnable task)

Methods inherited from class de.aristaflow.adept2.util.threading.AFThreadPoolExecutor

beforeExecute, newTaskFor, newTaskFor, setLogExecuteCallStack, updateQueueLimit

Methods inherited from class java.util.concurrent.ThreadPoolExecutor

allowCoreThreadTimeOut, allowsCoreThreadTimeOut, awaitTermination, finalize, getActiveCount, getCompletedTaskCount, getCorePoolSize, getKeepAliveTime, getLargestPoolSize, getMaximumPoolSize, getPoolSize, getQueue, getRejectedExecutionHandler, getTaskCount, getThreadFactory, isShutdown, isTerminated, isTerminating, prestartAllCoreThreads, prestartCoreThread, purge, remove, setCorePoolSize, setKeepAliveTime, setMaximumPoolSize, setRejectedExecutionHandler, setThreadFactory, shutdown, shutdownNow, terminated, toString

Methods inherited from class java.util.concurrent.AbstractExecutorService

invokeAll, invokeAll, invokeAny, invokeAny, submit, submit, submit

Methods inherited from class java.lang.Object

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

Field Detail

realCoreSize

protected final int realCoreSize

The normal core size of the pool.

realMaxSize

protected final int realMaxSize

The maximum size of the pool.

fullSize

protected final java.util.concurrent.atomic.AtomicBoolean fullSize

Whether the pool (its amount of core threads) is set to the maximum size.

workSize

protected final java.util.concurrent.atomic.AtomicInteger workSize

The amount of work currently in the pool. If this exceeds the normal core pool size, the core pool size is increased to the maximum size of the pool. If the amount of work goes below the normal core pool size, the core pool size will be reduced again.

Constructor Detail

CachedThreadPoolExecutor

public CachedThreadPoolExecutor(int corePoolSize,
                                int maxPoolSize,
                                boolean prestart,
                                Adept2ThreadFactory threadFactory)

Creates a new CachedThreadPoolExecutor with the given initial parameters and default rejected execution handler. The cached thread pool executor increases the corePoolSize to the maxPoolSize, if the work load exceeds the amount of core threads If the work load declines, the corePoolSize will be reduced to the original value.

Parameters:

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

maxPoolSize - The maximum number of threads to allow in the pool.

prestart - Whether all core threads should be prestarted.

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

Method Detail

execute

public void execute(java.lang.Runnable task)

Specified by:

execute in interface java.util.concurrent.Executor

Overrides:

execute in class AFThreadPoolExecutor

afterExecute

protected void afterExecute(java.lang.Runnable r,
                            java.lang.Throwable t)

Overrides:

afterExecute in class AFThreadPoolExecutor