com.github.nill14.utils.executor

Class PriorityExecutor

java.lang.Object

java.util.concurrent.AbstractExecutorService

java.util.concurrent.ThreadPoolExecutor

com.github.nill14.utils.executor.PriorityExecutor

All Implemented Interfaces:

Executor, ExecutorService

public class PriorityExecutor
extends ThreadPoolExecutor

Explanation about corePoolSize vs maxPoolSize http://www.bigsoft.co.uk/blog/index.php/2009/11/27/rules-of-a-threadpoolexecutor-pool-size

Nested Class Summary

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

ThreadPoolExecutor.AbortPolicy, ThreadPoolExecutor.CallerRunsPolicy, ThreadPoolExecutor.DiscardOldestPolicy, ThreadPoolExecutor.DiscardPolicy

Constructor Summary

Constructors

Constructor and Description
PriorityExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue) Creates a new ThreadPoolExecutor with the given initial parameters and default thread factory and rejected execution handler.
PriorityExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue, RejectedExecutionHandler handler) Creates a new ThreadPoolExecutor with the given initial parameters and default thread factory.
PriorityExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue, ThreadFactory threadFactory) Creates a new ThreadPoolExecutor with the given initial parameters and default rejected execution handler.
PriorityExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue, ThreadFactory threadFactory, RejectedExecutionHandler handler) Creates a new ThreadPoolExecutor with the given initial parameters.

Method Summary

Modifier and Type	Method and Description
static ExecutorService	newFixedThreadPool(int nThreads) Creates a thread pool that reuses a fixed number of threads operating off a shared unbounded queue.

Methods inherited from class java.util.concurrent.ThreadPoolExecutor

allowCoreThreadTimeOut, allowsCoreThreadTimeOut, awaitTermination, execute, 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, toString

Methods inherited from class java.util.concurrent.AbstractExecutorService

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

Methods inherited from class java.lang.Object

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

Constructor Detail

PriorityExecutor

public PriorityExecutor(int corePoolSize,
                        int maximumPoolSize,
                        long keepAliveTime,
                        TimeUnit unit,
                        BlockingQueue<Runnable> workQueue,
                        RejectedExecutionHandler handler)

Creates a new ThreadPoolExecutor with the given initial parameters and default thread factory.

Parameters:

corePoolSize - the number of threads to keep in the pool, even if they are idle, unless allowCoreThreadTimeOut is set

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

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

unit - the time unit for the keepAliveTime argument

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.

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

Throws:

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

NullPointerException - if workQueue or handler is null

PriorityExecutor

public PriorityExecutor(int corePoolSize,
                        int maximumPoolSize,
                        long keepAliveTime,
                        TimeUnit unit,
                        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 pool, even if they are idle, unless allowCoreThreadTimeOut is set

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

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

unit - the time unit for the keepAliveTime argument

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

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

PriorityExecutor

public PriorityExecutor(int corePoolSize,
                        int maximumPoolSize,
                        long keepAliveTime,
                        TimeUnit unit,
                        BlockingQueue<Runnable> workQueue,
                        ThreadFactory threadFactory)

Creates a new ThreadPoolExecutor with the given initial parameters and default rejected execution handler.

Parameters:

corePoolSize - the number of threads to keep in the pool, even if they are idle, unless allowCoreThreadTimeOut is set

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

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

unit - the time unit for the keepAliveTime argument

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

Throws:

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

NullPointerException - if workQueue or threadFactory is null

PriorityExecutor

public PriorityExecutor(int corePoolSize,
                        int maximumPoolSize,
                        long keepAliveTime,
                        TimeUnit unit,
                        BlockingQueue<Runnable> workQueue)

Creates a new ThreadPoolExecutor with the given initial parameters and default thread factory and rejected execution handler. It may be more convenient to use one of the Executors factory methods instead of this general purpose constructor.

Parameters:

corePoolSize - the number of threads to keep in the pool, even if they are idle, unless allowCoreThreadTimeOut is set

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

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

unit - the time unit for the keepAliveTime argument

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.

Throws:

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

NullPointerException - if workQueue is null

Method Detail

newFixedThreadPool

public static ExecutorService 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