net.tascalate.concurrent

Class TaskExecutors

java.lang.Object

net.tascalate.concurrent.TaskExecutors

public class TaskExecutors
extends Object

The drop-in replacement for Executors utility class that returns various useful implementations of TaskExecutorService instead of standard ExecutorService.

Author:

vsilaev

Method Summary

Modifier and Type	Method and Description
static TaskExecutorService	adapt(ExecutorService executorService)
static TaskExecutorService	newCachedThreadPool() Creates a thread pool that creates new threads as needed, but will reuse previously constructed threads when they are available.
static TaskExecutorService	newCachedThreadPool(ThreadFactory threadFactory) Creates a thread pool that creates new threads as needed, but will reuse previously constructed threads when they are available, and uses the provided ThreadFactory to create new threads when needed.
static TaskExecutorService	newFixedThreadPool(int nThreads) Creates a thread pool that reuses a fixed number of threads operating off a shared unbounded queue.
static TaskExecutorService	newFixedThreadPool(int nThreads, ThreadFactory threadFactory) Creates a thread pool that reuses a fixed number of threads operating off a shared unbounded queue, using the provided ThreadFactory to create new threads when needed.
static TaskExecutorService	newSingleThreadExecutor() Creates an Executor that uses a single worker thread operating off an unbounded queue.
static TaskExecutorService	newSingleThreadExecutor(ThreadFactory threadFactory) Creates an Executor that uses a single worker thread operating off an unbounded queue, and uses the provided ThreadFactory to create a new thread when needed.
static ThreadFactoryBuilder	newThreadFactory()
static ThreadGroupBuilder	newThreadGroup()

Methods inherited from class java.lang.Object

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

Method Detail

newThreadFactory

public static ThreadFactoryBuilder newThreadFactory()

newThreadGroup

public static ThreadGroupBuilder newThreadGroup()

newFixedThreadPool

public static TaskExecutorService newFixedThreadPool(int nThreads)

Creates a thread pool that reuses a fixed number of threads operating off a shared unbounded queue. At any point, at most nThreads threads will be active processing tasks. If additional tasks are submitted when all threads are active, they will wait in the queue until a thread is available. If any thread terminates due to a failure during execution prior to shutdown, a new one will take its place if needed to execute subsequent tasks. The threads in the pool will exist until it is explicitly shutdown.

Parameters:

nThreads - the number of threads in the pool

Returns:

the newly created thread pool

Throws:

IllegalArgumentException - if nThreads <= 0

newFixedThreadPool

public static TaskExecutorService newFixedThreadPool(int nThreads,
                                                     ThreadFactory threadFactory)

Creates a thread pool that reuses a fixed number of threads operating off a shared unbounded queue, using the provided ThreadFactory to create new threads when needed. At any point, at most nThreads threads will be active processing tasks. If additional tasks are submitted when all threads are active, they will wait in the queue until a thread is available. If any thread terminates due to a failure during execution prior to shutdown, a new one will take its place if needed to execute subsequent tasks. The threads in the pool will exist until it is explicitly shutdown.

Parameters:

nThreads - the number of threads in the pool

threadFactory - the factory to use when creating new threads

Returns:

the newly created thread pool

Throws:

NullPointerException - if threadFactory is null

IllegalArgumentException - if nThreads <= 0

newCachedThreadPool

public static TaskExecutorService newCachedThreadPool()

Creates a thread pool that creates new threads as needed, but will reuse previously constructed threads when they are available. These pools will typically improve the performance of programs that execute many short-lived asynchronous tasks. Calls to execute will reuse previously constructed threads if available. If no existing thread is available, a new thread will be created and added to the pool. Threads that have not been used for sixty seconds are terminated and removed from the cache. Thus, a pool that remains idle for long enough will not consume any resources. Note that pools with similar properties but different details (for example, timeout parameters) may be created using ThreadPoolExecutor constructors.

Returns:

the newly created thread pool

newCachedThreadPool

public static TaskExecutorService newCachedThreadPool(ThreadFactory threadFactory)

Creates a thread pool that creates new threads as needed, but will reuse previously constructed threads when they are available, and uses the provided ThreadFactory to create new threads when needed.

Parameters:

threadFactory - the factory to use when creating new threads

Returns:

the newly created thread pool

Throws:

NullPointerException - if threadFactory is null

newSingleThreadExecutor

public static TaskExecutorService newSingleThreadExecutor()

Creates an Executor that uses a single worker thread operating off an unbounded queue. (Note however that if this single thread terminates due to a failure during execution prior to shutdown, a new one will take its place if needed to execute subsequent tasks.) Tasks are guaranteed to execute sequentially, and no more than one task will be active at any given time. Unlike the otherwise equivalent newFixedThreadPool(1) the returned executor is guaranteed not to be reconfigurable to use additional threads.

Returns:

the newly created single-threaded Executor

newSingleThreadExecutor

public static TaskExecutorService newSingleThreadExecutor(ThreadFactory threadFactory)

Creates an Executor that uses a single worker thread operating off an unbounded queue, and uses the provided ThreadFactory to create a new thread when needed. Unlike the otherwise equivalent newFixedThreadPool(1, threadFactory) the returned executor is guaranteed not to be reconfigurable to use additional threads.

Parameters:

threadFactory - the factory to use when creating new threads

Returns:

the newly created single-threaded Executor

Throws:

NullPointerException - if threadFactory is null

adapt

public static TaskExecutorService adapt(ExecutorService executorService)