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/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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/*
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* This file is available under and governed by the GNU General Public
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* License version 2 only, as published by the Free Software Foundation.
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* However, the following notice accompanied the original version of this
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* file:
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*
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* Written by Doug Lea with assistance from members of JCP JSR-166
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* Expert Group and released to the public domain, as explained at
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* http://creativecommons.org/publicdomain/zero/1.0/
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*/
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package java.util.concurrent;
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import java.util.*;
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import java.util.concurrent.atomic.AtomicInteger;
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import java.security.AccessController;
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import java.security.PrivilegedAction;
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import java.security.PrivilegedExceptionAction;
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/**
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* Factory and utility methods for {@link Executor}, {@link
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* ExecutorService}, {@link ScheduledExecutorService}, {@link
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* ThreadFactory}, and {@link Callable} classes defined in this
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* package. This class supports the following kinds of methods:
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*
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* <ul>
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* <li> Methods that create and return an {@link ExecutorService}
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* set up with commonly useful configuration settings.
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* <li> Methods that create and return a {@link ScheduledExecutorService}
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* set up with commonly useful configuration settings.
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* <li> Methods that create and return a "wrapped" ExecutorService, that
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* disables reconfiguration by making implementation-specific methods
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* inaccessible.
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* <li> Methods that create and return a {@link ThreadFactory}
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* that sets newly created threads to a known state.
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* <li> Methods that create and return a {@link Callable}
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* out of other closure-like forms, so they can be used
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* in execution methods requiring <tt>Callable</tt>.
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* </ul>
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*
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* @since 1.5
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* @author Doug Lea
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*/
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public class Executors {
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/**
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* Creates a thread pool that reuses a fixed number of threads
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* operating off a shared unbounded queue. At any point, at most
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* <tt>nThreads</tt> threads will be active processing tasks.
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* If additional tasks are submitted when all threads are active,
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* they will wait in the queue until a thread is available.
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* If any thread terminates due to a failure during execution
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* prior to shutdown, a new one will take its place if needed to
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* execute subsequent tasks. The threads in the pool will exist
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* until it is explicitly {@link ExecutorService#shutdown shutdown}.
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*
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* @param nThreads the number of threads in the pool
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* @return the newly created thread pool
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* @throws IllegalArgumentException if {@code nThreads <= 0}
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*/
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public static ExecutorService newFixedThreadPool(int nThreads) {
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return new ThreadPoolExecutor(nThreads, nThreads,
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0L, TimeUnit.MILLISECONDS,
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new LinkedBlockingQueue<Runnable>());
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}
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/**
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* Creates a thread pool that reuses a fixed number of threads
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* operating off a shared unbounded queue, using the provided
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* ThreadFactory to create new threads when needed. At any point,
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* at most <tt>nThreads</tt> threads will be active processing
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* tasks. If additional tasks are submitted when all threads are
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* active, they will wait in the queue until a thread is
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* available. If any thread terminates due to a failure during
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* execution prior to shutdown, a new one will take its place if
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* needed to execute subsequent tasks. The threads in the pool will
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* exist until it is explicitly {@link ExecutorService#shutdown
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* shutdown}.
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*
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* @param nThreads the number of threads in the pool
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* @param threadFactory the factory to use when creating new threads
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* @return the newly created thread pool
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* @throws NullPointerException if threadFactory is null
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* @throws IllegalArgumentException if {@code nThreads <= 0}
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*/
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public static ExecutorService newFixedThreadPool(int nThreads, ThreadFactory threadFactory) {
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return new ThreadPoolExecutor(nThreads, nThreads,
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0L, TimeUnit.MILLISECONDS,
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new LinkedBlockingQueue<Runnable>(),
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threadFactory);
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}
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/**
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* Creates an Executor that uses a single worker thread operating
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* off an unbounded queue. (Note however that if this single
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* thread terminates due to a failure during execution prior to
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* shutdown, a new one will take its place if needed to execute
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* subsequent tasks.) Tasks are guaranteed to execute
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* sequentially, and no more than one task will be active at any
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* given time. Unlike the otherwise equivalent
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* <tt>newFixedThreadPool(1)</tt> the returned executor is
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* guaranteed not to be reconfigurable to use additional threads.
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*
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* @return the newly created single-threaded Executor
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*/
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public static ExecutorService newSingleThreadExecutor() {
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return new FinalizableDelegatedExecutorService
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(new ThreadPoolExecutor(1, 1,
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0L, TimeUnit.MILLISECONDS,
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new LinkedBlockingQueue<Runnable>()));
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}
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/**
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* Creates an Executor that uses a single worker thread operating
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* off an unbounded queue, and uses the provided ThreadFactory to
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* create a new thread when needed. Unlike the otherwise
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* equivalent <tt>newFixedThreadPool(1, threadFactory)</tt> the
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* returned executor is guaranteed not to be reconfigurable to use
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* additional threads.
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*
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* @param threadFactory the factory to use when creating new
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* threads
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*
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* @return the newly created single-threaded Executor
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* @throws NullPointerException if threadFactory is null
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*/
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public static ExecutorService newSingleThreadExecutor(ThreadFactory threadFactory) {
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return new FinalizableDelegatedExecutorService
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(new ThreadPoolExecutor(1, 1,
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0L, TimeUnit.MILLISECONDS,
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new LinkedBlockingQueue<Runnable>(),
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threadFactory));
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}
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/**
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* Creates a thread pool that creates new threads as needed, but
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* will reuse previously constructed threads when they are
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* available. These pools will typically improve the performance
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* of programs that execute many short-lived asynchronous tasks.
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* Calls to <tt>execute</tt> will reuse previously constructed
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* threads if available. If no existing thread is available, a new
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* thread will be created and added to the pool. Threads that have
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* not been used for sixty seconds are terminated and removed from
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* the cache. Thus, a pool that remains idle for long enough will
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* not consume any resources. Note that pools with similar
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* properties but different details (for example, timeout parameters)
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* may be created using {@link ThreadPoolExecutor} constructors.
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*
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* @return the newly created thread pool
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*/
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public static ExecutorService newCachedThreadPool() {
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return new ThreadPoolExecutor(0, Integer.MAX_VALUE,
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60L, TimeUnit.SECONDS,
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new SynchronousQueue<Runnable>());
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}
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/**
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* Creates a thread pool that creates new threads as needed, but
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* will reuse previously constructed threads when they are
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* available, and uses the provided
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* ThreadFactory to create new threads when needed.
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* @param threadFactory the factory to use when creating new threads
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* @return the newly created thread pool
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* @throws NullPointerException if threadFactory is null
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*/
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public static ExecutorService newCachedThreadPool(ThreadFactory threadFactory) {
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return new ThreadPoolExecutor(0, Integer.MAX_VALUE,
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60L, TimeUnit.SECONDS,
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new SynchronousQueue<Runnable>(),
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threadFactory);
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}
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/**
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* Creates a single-threaded executor that can schedule commands
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* to run after a given delay, or to execute periodically.
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* (Note however that if this single
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* thread terminates due to a failure during execution prior to
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* shutdown, a new one will take its place if needed to execute
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* subsequent tasks.) Tasks are guaranteed to execute
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* sequentially, and no more than one task will be active at any
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* given time. Unlike the otherwise equivalent
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* <tt>newScheduledThreadPool(1)</tt> the returned executor is
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* guaranteed not to be reconfigurable to use additional threads.
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* @return the newly created scheduled executor
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*/
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public static ScheduledExecutorService newSingleThreadScheduledExecutor() {
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return new DelegatedScheduledExecutorService
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(new ScheduledThreadPoolExecutor(1));
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}
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/**
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* Creates a single-threaded executor that can schedule commands
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* to run after a given delay, or to execute periodically. (Note
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* however that if this single thread terminates due to a failure
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* during execution prior to shutdown, a new one will take its
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* place if needed to execute subsequent tasks.) Tasks are
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* guaranteed to execute sequentially, and no more than one task
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* will be active at any given time. Unlike the otherwise
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* equivalent <tt>newScheduledThreadPool(1, threadFactory)</tt>
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* the returned executor is guaranteed not to be reconfigurable to
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* use additional threads.
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* @param threadFactory the factory to use when creating new
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* threads
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* @return a newly created scheduled executor
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* @throws NullPointerException if threadFactory is null
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*/
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public static ScheduledExecutorService newSingleThreadScheduledExecutor(ThreadFactory threadFactory) {
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return new DelegatedScheduledExecutorService
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(new ScheduledThreadPoolExecutor(1, threadFactory));
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}
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/**
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* Creates a thread pool that can schedule commands to run after a
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* given delay, or to execute periodically.
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* @param corePoolSize the number of threads to keep in the pool,
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* even if they are idle.
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* @return a newly created scheduled thread pool
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* @throws IllegalArgumentException if {@code corePoolSize < 0}
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*/
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public static ScheduledExecutorService newScheduledThreadPool(int corePoolSize) {
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return new ScheduledThreadPoolExecutor(corePoolSize);
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}
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/**
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* Creates a thread pool that can schedule commands to run after a
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* given delay, or to execute periodically.
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* @param corePoolSize the number of threads to keep in the pool,
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* even if they are idle.
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* @param threadFactory the factory to use when the executor
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* creates a new thread.
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* @return a newly created scheduled thread pool
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* @throws IllegalArgumentException if {@code corePoolSize < 0}
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* @throws NullPointerException if threadFactory is null
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*/
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public static ScheduledExecutorService newScheduledThreadPool(
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int corePoolSize, ThreadFactory threadFactory) {
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return new ScheduledThreadPoolExecutor(corePoolSize, threadFactory);
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}
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/**
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* Returns an object that delegates all defined {@link
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* ExecutorService} methods to the given executor, but not any
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* other methods that might otherwise be accessible using
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* casts. This provides a way to safely "freeze" configuration and
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* disallow tuning of a given concrete implementation.
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* @param executor the underlying implementation
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* @return an <tt>ExecutorService</tt> instance
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* @throws NullPointerException if executor null
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*/
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public static ExecutorService unconfigurableExecutorService(ExecutorService executor) {
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if (executor == null)
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throw new NullPointerException();
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return new DelegatedExecutorService(executor);
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}
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/**
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* Returns an object that delegates all defined {@link
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* ScheduledExecutorService} methods to the given executor, but
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* not any other methods that might otherwise be accessible using
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* casts. This provides a way to safely "freeze" configuration and
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* disallow tuning of a given concrete implementation.
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* @param executor the underlying implementation
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* @return a <tt>ScheduledExecutorService</tt> instance
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* @throws NullPointerException if executor null
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*/
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public static ScheduledExecutorService unconfigurableScheduledExecutorService(ScheduledExecutorService executor) {
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if (executor == null)
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throw new NullPointerException();
|
jaroslav@1890
|
293 |
return new DelegatedScheduledExecutorService(executor);
|
jaroslav@1890
|
294 |
}
|
jaroslav@1890
|
295 |
|
jaroslav@1890
|
296 |
/**
|
jaroslav@1890
|
297 |
* Returns a default thread factory used to create new threads.
|
jaroslav@1890
|
298 |
* This factory creates all new threads used by an Executor in the
|
jaroslav@1890
|
299 |
* same {@link ThreadGroup}. If there is a {@link
|
jaroslav@1890
|
300 |
* java.lang.SecurityManager}, it uses the group of {@link
|
jaroslav@1890
|
301 |
* System#getSecurityManager}, else the group of the thread
|
jaroslav@1890
|
302 |
* invoking this <tt>defaultThreadFactory</tt> method. Each new
|
jaroslav@1890
|
303 |
* thread is created as a non-daemon thread with priority set to
|
jaroslav@1890
|
304 |
* the smaller of <tt>Thread.NORM_PRIORITY</tt> and the maximum
|
jaroslav@1890
|
305 |
* priority permitted in the thread group. New threads have names
|
jaroslav@1890
|
306 |
* accessible via {@link Thread#getName} of
|
jaroslav@1890
|
307 |
* <em>pool-N-thread-M</em>, where <em>N</em> is the sequence
|
jaroslav@1890
|
308 |
* number of this factory, and <em>M</em> is the sequence number
|
jaroslav@1890
|
309 |
* of the thread created by this factory.
|
jaroslav@1890
|
310 |
* @return a thread factory
|
jaroslav@1890
|
311 |
*/
|
jaroslav@1890
|
312 |
public static ThreadFactory defaultThreadFactory() {
|
jaroslav@1890
|
313 |
return new DefaultThreadFactory();
|
jaroslav@1890
|
314 |
}
|
jaroslav@1890
|
315 |
|
jaroslav@1890
|
316 |
/**
|
jaroslav@1890
|
317 |
* Returns a thread factory used to create new threads that
|
jaroslav@1890
|
318 |
* have the same permissions as the current thread.
|
jaroslav@1890
|
319 |
* This factory creates threads with the same settings as {@link
|
jaroslav@1890
|
320 |
* Executors#defaultThreadFactory}, additionally setting the
|
jaroslav@1890
|
321 |
* AccessControlContext and contextClassLoader of new threads to
|
jaroslav@1890
|
322 |
* be the same as the thread invoking this
|
jaroslav@1890
|
323 |
* <tt>privilegedThreadFactory</tt> method. A new
|
jaroslav@1890
|
324 |
* <tt>privilegedThreadFactory</tt> can be created within an
|
jaroslav@1890
|
325 |
* {@link AccessController#doPrivileged} action setting the
|
jaroslav@1890
|
326 |
* current thread's access control context to create threads with
|
jaroslav@1890
|
327 |
* the selected permission settings holding within that action.
|
jaroslav@1890
|
328 |
*
|
jaroslav@1890
|
329 |
* <p> Note that while tasks running within such threads will have
|
jaroslav@1890
|
330 |
* the same access control and class loader settings as the
|
jaroslav@1890
|
331 |
* current thread, they need not have the same {@link
|
jaroslav@1890
|
332 |
* java.lang.ThreadLocal} or {@link
|
jaroslav@1890
|
333 |
* java.lang.InheritableThreadLocal} values. If necessary,
|
jaroslav@1890
|
334 |
* particular values of thread locals can be set or reset before
|
jaroslav@1890
|
335 |
* any task runs in {@link ThreadPoolExecutor} subclasses using
|
jaroslav@1890
|
336 |
* {@link ThreadPoolExecutor#beforeExecute}. Also, if it is
|
jaroslav@1890
|
337 |
* necessary to initialize worker threads to have the same
|
jaroslav@1890
|
338 |
* InheritableThreadLocal settings as some other designated
|
jaroslav@1890
|
339 |
* thread, you can create a custom ThreadFactory in which that
|
jaroslav@1890
|
340 |
* thread waits for and services requests to create others that
|
jaroslav@1890
|
341 |
* will inherit its values.
|
jaroslav@1890
|
342 |
*
|
jaroslav@1890
|
343 |
* @return a thread factory
|
jaroslav@1890
|
344 |
* @throws AccessControlException if the current access control
|
jaroslav@1890
|
345 |
* context does not have permission to both get and set context
|
jaroslav@1890
|
346 |
* class loader.
|
jaroslav@1890
|
347 |
*/
|
jaroslav@1890
|
348 |
public static ThreadFactory privilegedThreadFactory() {
|
jaroslav@1895
|
349 |
throw new SecurityException();
|
jaroslav@1890
|
350 |
}
|
jaroslav@1890
|
351 |
|
jaroslav@1890
|
352 |
/**
|
jaroslav@1890
|
353 |
* Returns a {@link Callable} object that, when
|
jaroslav@1890
|
354 |
* called, runs the given task and returns the given result. This
|
jaroslav@1890
|
355 |
* can be useful when applying methods requiring a
|
jaroslav@1890
|
356 |
* <tt>Callable</tt> to an otherwise resultless action.
|
jaroslav@1890
|
357 |
* @param task the task to run
|
jaroslav@1890
|
358 |
* @param result the result to return
|
jaroslav@1890
|
359 |
* @return a callable object
|
jaroslav@1890
|
360 |
* @throws NullPointerException if task null
|
jaroslav@1890
|
361 |
*/
|
jaroslav@1890
|
362 |
public static <T> Callable<T> callable(Runnable task, T result) {
|
jaroslav@1890
|
363 |
if (task == null)
|
jaroslav@1890
|
364 |
throw new NullPointerException();
|
jaroslav@1890
|
365 |
return new RunnableAdapter<T>(task, result);
|
jaroslav@1890
|
366 |
}
|
jaroslav@1890
|
367 |
|
jaroslav@1890
|
368 |
/**
|
jaroslav@1890
|
369 |
* Returns a {@link Callable} object that, when
|
jaroslav@1890
|
370 |
* called, runs the given task and returns <tt>null</tt>.
|
jaroslav@1890
|
371 |
* @param task the task to run
|
jaroslav@1890
|
372 |
* @return a callable object
|
jaroslav@1890
|
373 |
* @throws NullPointerException if task null
|
jaroslav@1890
|
374 |
*/
|
jaroslav@1890
|
375 |
public static Callable<Object> callable(Runnable task) {
|
jaroslav@1890
|
376 |
if (task == null)
|
jaroslav@1890
|
377 |
throw new NullPointerException();
|
jaroslav@1890
|
378 |
return new RunnableAdapter<Object>(task, null);
|
jaroslav@1890
|
379 |
}
|
jaroslav@1890
|
380 |
|
jaroslav@1890
|
381 |
/**
|
jaroslav@1890
|
382 |
* Returns a {@link Callable} object that, when
|
jaroslav@1890
|
383 |
* called, runs the given privileged action and returns its result.
|
jaroslav@1890
|
384 |
* @param action the privileged action to run
|
jaroslav@1890
|
385 |
* @return a callable object
|
jaroslav@1890
|
386 |
* @throws NullPointerException if action null
|
jaroslav@1890
|
387 |
*/
|
jaroslav@1890
|
388 |
public static Callable<Object> callable(final PrivilegedAction<?> action) {
|
jaroslav@1890
|
389 |
if (action == null)
|
jaroslav@1890
|
390 |
throw new NullPointerException();
|
jaroslav@1890
|
391 |
return new Callable<Object>() {
|
jaroslav@1890
|
392 |
public Object call() { return action.run(); }};
|
jaroslav@1890
|
393 |
}
|
jaroslav@1890
|
394 |
|
jaroslav@1890
|
395 |
/**
|
jaroslav@1890
|
396 |
* Returns a {@link Callable} object that, when
|
jaroslav@1890
|
397 |
* called, runs the given privileged exception action and returns
|
jaroslav@1890
|
398 |
* its result.
|
jaroslav@1890
|
399 |
* @param action the privileged exception action to run
|
jaroslav@1890
|
400 |
* @return a callable object
|
jaroslav@1890
|
401 |
* @throws NullPointerException if action null
|
jaroslav@1890
|
402 |
*/
|
jaroslav@1890
|
403 |
public static Callable<Object> callable(final PrivilegedExceptionAction<?> action) {
|
jaroslav@1890
|
404 |
if (action == null)
|
jaroslav@1890
|
405 |
throw new NullPointerException();
|
jaroslav@1890
|
406 |
return new Callable<Object>() {
|
jaroslav@1890
|
407 |
public Object call() throws Exception { return action.run(); }};
|
jaroslav@1890
|
408 |
}
|
jaroslav@1890
|
409 |
|
jaroslav@1890
|
410 |
/**
|
jaroslav@1890
|
411 |
* Returns a {@link Callable} object that will, when
|
jaroslav@1890
|
412 |
* called, execute the given <tt>callable</tt> under the current
|
jaroslav@1890
|
413 |
* access control context. This method should normally be
|
jaroslav@1890
|
414 |
* invoked within an {@link AccessController#doPrivileged} action
|
jaroslav@1890
|
415 |
* to create callables that will, if possible, execute under the
|
jaroslav@1890
|
416 |
* selected permission settings holding within that action; or if
|
jaroslav@1890
|
417 |
* not possible, throw an associated {@link
|
jaroslav@1890
|
418 |
* AccessControlException}.
|
jaroslav@1890
|
419 |
* @param callable the underlying task
|
jaroslav@1890
|
420 |
* @return a callable object
|
jaroslav@1890
|
421 |
* @throws NullPointerException if callable null
|
jaroslav@1890
|
422 |
*
|
jaroslav@1890
|
423 |
*/
|
jaroslav@1890
|
424 |
public static <T> Callable<T> privilegedCallable(Callable<T> callable) {
|
jaroslav@1890
|
425 |
if (callable == null)
|
jaroslav@1890
|
426 |
throw new NullPointerException();
|
jaroslav@1890
|
427 |
return new PrivilegedCallable<T>(callable);
|
jaroslav@1890
|
428 |
}
|
jaroslav@1890
|
429 |
|
jaroslav@1890
|
430 |
/**
|
jaroslav@1890
|
431 |
* Returns a {@link Callable} object that will, when
|
jaroslav@1890
|
432 |
* called, execute the given <tt>callable</tt> under the current
|
jaroslav@1890
|
433 |
* access control context, with the current context class loader
|
jaroslav@1890
|
434 |
* as the context class loader. This method should normally be
|
jaroslav@1890
|
435 |
* invoked within an {@link AccessController#doPrivileged} action
|
jaroslav@1890
|
436 |
* to create callables that will, if possible, execute under the
|
jaroslav@1890
|
437 |
* selected permission settings holding within that action; or if
|
jaroslav@1890
|
438 |
* not possible, throw an associated {@link
|
jaroslav@1890
|
439 |
* AccessControlException}.
|
jaroslav@1890
|
440 |
* @param callable the underlying task
|
jaroslav@1890
|
441 |
*
|
jaroslav@1890
|
442 |
* @return a callable object
|
jaroslav@1890
|
443 |
* @throws NullPointerException if callable null
|
jaroslav@1890
|
444 |
* @throws AccessControlException if the current access control
|
jaroslav@1890
|
445 |
* context does not have permission to both set and get context
|
jaroslav@1890
|
446 |
* class loader.
|
jaroslav@1890
|
447 |
*/
|
jaroslav@1890
|
448 |
public static <T> Callable<T> privilegedCallableUsingCurrentClassLoader(Callable<T> callable) {
|
jaroslav@1895
|
449 |
throw new SecurityException();
|
jaroslav@1890
|
450 |
}
|
jaroslav@1890
|
451 |
|
jaroslav@1890
|
452 |
// Non-public classes supporting the public methods
|
jaroslav@1890
|
453 |
|
jaroslav@1890
|
454 |
/**
|
jaroslav@1890
|
455 |
* A callable that runs given task and returns given result
|
jaroslav@1890
|
456 |
*/
|
jaroslav@1890
|
457 |
static final class RunnableAdapter<T> implements Callable<T> {
|
jaroslav@1890
|
458 |
final Runnable task;
|
jaroslav@1890
|
459 |
final T result;
|
jaroslav@1890
|
460 |
RunnableAdapter(Runnable task, T result) {
|
jaroslav@1890
|
461 |
this.task = task;
|
jaroslav@1890
|
462 |
this.result = result;
|
jaroslav@1890
|
463 |
}
|
jaroslav@1890
|
464 |
public T call() {
|
jaroslav@1890
|
465 |
task.run();
|
jaroslav@1890
|
466 |
return result;
|
jaroslav@1890
|
467 |
}
|
jaroslav@1890
|
468 |
}
|
jaroslav@1890
|
469 |
|
jaroslav@1890
|
470 |
/**
|
jaroslav@1890
|
471 |
* A callable that runs under established access control settings
|
jaroslav@1890
|
472 |
*/
|
jaroslav@1890
|
473 |
static final class PrivilegedCallable<T> implements Callable<T> {
|
jaroslav@1890
|
474 |
private final Callable<T> task;
|
jaroslav@1890
|
475 |
|
jaroslav@1890
|
476 |
PrivilegedCallable(Callable<T> task) {
|
jaroslav@1890
|
477 |
this.task = task;
|
jaroslav@1890
|
478 |
}
|
jaroslav@1890
|
479 |
|
jaroslav@1890
|
480 |
public T call() throws Exception {
|
jaroslav@1895
|
481 |
return task.call();
|
jaroslav@1890
|
482 |
}
|
jaroslav@1890
|
483 |
}
|
jaroslav@1890
|
484 |
|
jaroslav@1890
|
485 |
/**
|
jaroslav@1890
|
486 |
* The default thread factory
|
jaroslav@1890
|
487 |
*/
|
jaroslav@1890
|
488 |
static class DefaultThreadFactory implements ThreadFactory {
|
jaroslav@1890
|
489 |
private static final AtomicInteger poolNumber = new AtomicInteger(1);
|
jaroslav@1890
|
490 |
private final AtomicInteger threadNumber = new AtomicInteger(1);
|
jaroslav@1890
|
491 |
private final String namePrefix;
|
jaroslav@1890
|
492 |
|
jaroslav@1890
|
493 |
DefaultThreadFactory() {
|
jaroslav@1890
|
494 |
namePrefix = "pool-" +
|
jaroslav@1890
|
495 |
poolNumber.getAndIncrement() +
|
jaroslav@1890
|
496 |
"-thread-";
|
jaroslav@1890
|
497 |
}
|
jaroslav@1890
|
498 |
|
jaroslav@1890
|
499 |
public Thread newThread(Runnable r) {
|
jaroslav@1895
|
500 |
Thread t = new Thread(r,
|
jaroslav@1895
|
501 |
namePrefix + threadNumber.getAndIncrement()
|
jaroslav@1895
|
502 |
);
|
jaroslav@1890
|
503 |
if (t.isDaemon())
|
jaroslav@1890
|
504 |
t.setDaemon(false);
|
jaroslav@1890
|
505 |
if (t.getPriority() != Thread.NORM_PRIORITY)
|
jaroslav@1890
|
506 |
t.setPriority(Thread.NORM_PRIORITY);
|
jaroslav@1890
|
507 |
return t;
|
jaroslav@1890
|
508 |
}
|
jaroslav@1890
|
509 |
}
|
jaroslav@1890
|
510 |
|
jaroslav@1890
|
511 |
/**
|
jaroslav@1890
|
512 |
* A wrapper class that exposes only the ExecutorService methods
|
jaroslav@1890
|
513 |
* of an ExecutorService implementation.
|
jaroslav@1890
|
514 |
*/
|
jaroslav@1890
|
515 |
static class DelegatedExecutorService extends AbstractExecutorService {
|
jaroslav@1890
|
516 |
private final ExecutorService e;
|
jaroslav@1890
|
517 |
DelegatedExecutorService(ExecutorService executor) { e = executor; }
|
jaroslav@1890
|
518 |
public void execute(Runnable command) { e.execute(command); }
|
jaroslav@1890
|
519 |
public void shutdown() { e.shutdown(); }
|
jaroslav@1890
|
520 |
public List<Runnable> shutdownNow() { return e.shutdownNow(); }
|
jaroslav@1890
|
521 |
public boolean isShutdown() { return e.isShutdown(); }
|
jaroslav@1890
|
522 |
public boolean isTerminated() { return e.isTerminated(); }
|
jaroslav@1890
|
523 |
public boolean awaitTermination(long timeout, TimeUnit unit)
|
jaroslav@1890
|
524 |
throws InterruptedException {
|
jaroslav@1890
|
525 |
return e.awaitTermination(timeout, unit);
|
jaroslav@1890
|
526 |
}
|
jaroslav@1890
|
527 |
public Future<?> submit(Runnable task) {
|
jaroslav@1890
|
528 |
return e.submit(task);
|
jaroslav@1890
|
529 |
}
|
jaroslav@1890
|
530 |
public <T> Future<T> submit(Callable<T> task) {
|
jaroslav@1890
|
531 |
return e.submit(task);
|
jaroslav@1890
|
532 |
}
|
jaroslav@1890
|
533 |
public <T> Future<T> submit(Runnable task, T result) {
|
jaroslav@1890
|
534 |
return e.submit(task, result);
|
jaroslav@1890
|
535 |
}
|
jaroslav@1890
|
536 |
public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
|
jaroslav@1890
|
537 |
throws InterruptedException {
|
jaroslav@1890
|
538 |
return e.invokeAll(tasks);
|
jaroslav@1890
|
539 |
}
|
jaroslav@1890
|
540 |
public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks,
|
jaroslav@1890
|
541 |
long timeout, TimeUnit unit)
|
jaroslav@1890
|
542 |
throws InterruptedException {
|
jaroslav@1890
|
543 |
return e.invokeAll(tasks, timeout, unit);
|
jaroslav@1890
|
544 |
}
|
jaroslav@1890
|
545 |
public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
|
jaroslav@1890
|
546 |
throws InterruptedException, ExecutionException {
|
jaroslav@1890
|
547 |
return e.invokeAny(tasks);
|
jaroslav@1890
|
548 |
}
|
jaroslav@1890
|
549 |
public <T> T invokeAny(Collection<? extends Callable<T>> tasks,
|
jaroslav@1890
|
550 |
long timeout, TimeUnit unit)
|
jaroslav@1890
|
551 |
throws InterruptedException, ExecutionException, TimeoutException {
|
jaroslav@1890
|
552 |
return e.invokeAny(tasks, timeout, unit);
|
jaroslav@1890
|
553 |
}
|
jaroslav@1890
|
554 |
}
|
jaroslav@1890
|
555 |
|
jaroslav@1890
|
556 |
static class FinalizableDelegatedExecutorService
|
jaroslav@1890
|
557 |
extends DelegatedExecutorService {
|
jaroslav@1890
|
558 |
FinalizableDelegatedExecutorService(ExecutorService executor) {
|
jaroslav@1890
|
559 |
super(executor);
|
jaroslav@1890
|
560 |
}
|
jaroslav@1890
|
561 |
protected void finalize() {
|
jaroslav@1890
|
562 |
super.shutdown();
|
jaroslav@1890
|
563 |
}
|
jaroslav@1890
|
564 |
}
|
jaroslav@1890
|
565 |
|
jaroslav@1890
|
566 |
/**
|
jaroslav@1890
|
567 |
* A wrapper class that exposes only the ScheduledExecutorService
|
jaroslav@1890
|
568 |
* methods of a ScheduledExecutorService implementation.
|
jaroslav@1890
|
569 |
*/
|
jaroslav@1890
|
570 |
static class DelegatedScheduledExecutorService
|
jaroslav@1890
|
571 |
extends DelegatedExecutorService
|
jaroslav@1890
|
572 |
implements ScheduledExecutorService {
|
jaroslav@1890
|
573 |
private final ScheduledExecutorService e;
|
jaroslav@1890
|
574 |
DelegatedScheduledExecutorService(ScheduledExecutorService executor) {
|
jaroslav@1890
|
575 |
super(executor);
|
jaroslav@1890
|
576 |
e = executor;
|
jaroslav@1890
|
577 |
}
|
jaroslav@1890
|
578 |
public ScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
|
jaroslav@1890
|
579 |
return e.schedule(command, delay, unit);
|
jaroslav@1890
|
580 |
}
|
jaroslav@1890
|
581 |
public <V> ScheduledFuture<V> schedule(Callable<V> callable, long delay, TimeUnit unit) {
|
jaroslav@1890
|
582 |
return e.schedule(callable, delay, unit);
|
jaroslav@1890
|
583 |
}
|
jaroslav@1890
|
584 |
public ScheduledFuture<?> scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit) {
|
jaroslav@1890
|
585 |
return e.scheduleAtFixedRate(command, initialDelay, period, unit);
|
jaroslav@1890
|
586 |
}
|
jaroslav@1890
|
587 |
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit) {
|
jaroslav@1890
|
588 |
return e.scheduleWithFixedDelay(command, initialDelay, delay, unit);
|
jaroslav@1890
|
589 |
}
|
jaroslav@1890
|
590 |
}
|
jaroslav@1890
|
591 |
|
jaroslav@1890
|
592 |
|
jaroslav@1890
|
593 |
/** Cannot instantiate. */
|
jaroslav@1890
|
594 |
private Executors() {}
|
jaroslav@1890
|
595 |
}
|