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jeremybenn |
/*
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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/licenses/publicdomain
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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.AccessControlContext;
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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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import java.security.AccessControlException;
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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 <tt>nThreads <= 0</tt>
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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 <tt>nThreads <= 0</tt>
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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 <tt>corePoolSize < 0</tt>
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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 <tt>corePoolSize < 0</tt>
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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();
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return new DelegatedScheduledExecutorService(executor);
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}
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/**
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* Returns a default thread factory used to create new threads.
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* This factory creates all new threads used by an Executor in the
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* same {@link ThreadGroup}. If there is a {@link
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* java.lang.SecurityManager}, it uses the group of {@link
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* System#getSecurityManager}, else the group of the thread
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* invoking this <tt>defaultThreadFactory</tt> method. Each new
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* thread is created as a non-daemon thread with priority set to
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* the smaller of <tt>Thread.NORM_PRIORITY</tt> and the maximum
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* priority permitted in the thread group. New threads have names
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* accessible via {@link Thread#getName} of
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* <em>pool-N-thread-M</em>, where <em>N</em> is the sequence
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* number of this factory, and <em>M</em> is the sequence number
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* of the thread created by this factory.
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* @return a thread factory
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*/
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public static ThreadFactory defaultThreadFactory() {
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return new DefaultThreadFactory();
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}
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/**
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* Returns a thread factory used to create new threads that
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* have the same permissions as the current thread.
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* This factory creates threads with the same settings as {@link
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* Executors#defaultThreadFactory}, additionally setting the
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* AccessControlContext and contextClassLoader of new threads to
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* be the same as the thread invoking this
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* <tt>privilegedThreadFactory</tt> method. A new
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* <tt>privilegedThreadFactory</tt> can be created within an
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* {@link AccessController#doPrivileged} action setting the
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* current thread's access control context to create threads with
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* the selected permission settings holding within that action.
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*
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* <p> Note that while tasks running within such threads will have
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* the same access control and class loader settings as the
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* current thread, they need not have the same {@link
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* java.lang.ThreadLocal} or {@link
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* java.lang.InheritableThreadLocal} values. If necessary,
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* particular values of thread locals can be set or reset before
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* any task runs in {@link ThreadPoolExecutor} subclasses using
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* {@link ThreadPoolExecutor#beforeExecute}. Also, if it is
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* necessary to initialize worker threads to have the same
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* InheritableThreadLocal settings as some other designated
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* thread, you can create a custom ThreadFactory in which that
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* thread waits for and services requests to create others that
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* will inherit its values.
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*
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* @return a thread factory
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* @throws AccessControlException if the current access control
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* context does not have permission to both get and set context
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* class loader.
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*/
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public static ThreadFactory privilegedThreadFactory() {
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return new PrivilegedThreadFactory();
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}
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|
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/**
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* Returns a {@link Callable} object that, when
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* called, runs the given task and returns the given result. This
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* can be useful when applying methods requiring a
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* <tt>Callable</tt> to an otherwise resultless action.
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* @param task the task to run
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* @param result the result to return
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* @return a callable object
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* @throws NullPointerException if task null
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*/
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public static <T> Callable<T> callable(Runnable task, T result) {
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if (task == null)
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throw new NullPointerException();
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return new RunnableAdapter<T>(task, result);
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}
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|
341 |
|
|
/**
|
342 |
|
|
* Returns a {@link Callable} object that, when
|
343 |
|
|
* called, runs the given task and returns <tt>null</tt>.
|
344 |
|
|
* @param task the task to run
|
345 |
|
|
* @return a callable object
|
346 |
|
|
* @throws NullPointerException if task null
|
347 |
|
|
*/
|
348 |
|
|
public static Callable<Object> callable(Runnable task) {
|
349 |
|
|
if (task == null)
|
350 |
|
|
throw new NullPointerException();
|
351 |
|
|
return new RunnableAdapter<Object>(task, null);
|
352 |
|
|
}
|
353 |
|
|
|
354 |
|
|
/**
|
355 |
|
|
* Returns a {@link Callable} object that, when
|
356 |
|
|
* called, runs the given privileged action and returns its result.
|
357 |
|
|
* @param action the privileged action to run
|
358 |
|
|
* @return a callable object
|
359 |
|
|
* @throws NullPointerException if action null
|
360 |
|
|
*/
|
361 |
|
|
public static Callable<Object> callable(final PrivilegedAction<?> action) {
|
362 |
|
|
if (action == null)
|
363 |
|
|
throw new NullPointerException();
|
364 |
|
|
return new Callable<Object>() {
|
365 |
|
|
public Object call() { return action.run(); }};
|
366 |
|
|
}
|
367 |
|
|
|
368 |
|
|
/**
|
369 |
|
|
* Returns a {@link Callable} object that, when
|
370 |
|
|
* called, runs the given privileged exception action and returns
|
371 |
|
|
* its result.
|
372 |
|
|
* @param action the privileged exception action to run
|
373 |
|
|
* @return a callable object
|
374 |
|
|
* @throws NullPointerException if action null
|
375 |
|
|
*/
|
376 |
|
|
public static Callable<Object> callable(final PrivilegedExceptionAction<?> action) {
|
377 |
|
|
if (action == null)
|
378 |
|
|
throw new NullPointerException();
|
379 |
|
|
return new Callable<Object>() {
|
380 |
|
|
public Object call() throws Exception { return action.run(); }};
|
381 |
|
|
}
|
382 |
|
|
|
383 |
|
|
/**
|
384 |
|
|
* Returns a {@link Callable} object that will, when
|
385 |
|
|
* called, execute the given <tt>callable</tt> under the current
|
386 |
|
|
* access control context. This method should normally be
|
387 |
|
|
* invoked within an {@link AccessController#doPrivileged} action
|
388 |
|
|
* to create callables that will, if possible, execute under the
|
389 |
|
|
* selected permission settings holding within that action; or if
|
390 |
|
|
* not possible, throw an associated {@link
|
391 |
|
|
* AccessControlException}.
|
392 |
|
|
* @param callable the underlying task
|
393 |
|
|
* @return a callable object
|
394 |
|
|
* @throws NullPointerException if callable null
|
395 |
|
|
*
|
396 |
|
|
*/
|
397 |
|
|
public static <T> Callable<T> privilegedCallable(Callable<T> callable) {
|
398 |
|
|
if (callable == null)
|
399 |
|
|
throw new NullPointerException();
|
400 |
|
|
return new PrivilegedCallable<T>(callable);
|
401 |
|
|
}
|
402 |
|
|
|
403 |
|
|
/**
|
404 |
|
|
* Returns a {@link Callable} object that will, when
|
405 |
|
|
* called, execute the given <tt>callable</tt> under the current
|
406 |
|
|
* access control context, with the current context class loader
|
407 |
|
|
* as the context class loader. This method should normally be
|
408 |
|
|
* invoked within an {@link AccessController#doPrivileged} action
|
409 |
|
|
* to create callables that will, if possible, execute under the
|
410 |
|
|
* selected permission settings holding within that action; or if
|
411 |
|
|
* not possible, throw an associated {@link
|
412 |
|
|
* AccessControlException}.
|
413 |
|
|
* @param callable the underlying task
|
414 |
|
|
*
|
415 |
|
|
* @return a callable object
|
416 |
|
|
* @throws NullPointerException if callable null
|
417 |
|
|
* @throws AccessControlException if the current access control
|
418 |
|
|
* context does not have permission to both set and get context
|
419 |
|
|
* class loader.
|
420 |
|
|
*/
|
421 |
|
|
public static <T> Callable<T> privilegedCallableUsingCurrentClassLoader(Callable<T> callable) {
|
422 |
|
|
if (callable == null)
|
423 |
|
|
throw new NullPointerException();
|
424 |
|
|
return new PrivilegedCallableUsingCurrentClassLoader<T>(callable);
|
425 |
|
|
}
|
426 |
|
|
|
427 |
|
|
// Non-public classes supporting the public methods
|
428 |
|
|
|
429 |
|
|
/**
|
430 |
|
|
* A callable that runs given task and returns given result
|
431 |
|
|
*/
|
432 |
|
|
static final class RunnableAdapter<T> implements Callable<T> {
|
433 |
|
|
final Runnable task;
|
434 |
|
|
final T result;
|
435 |
|
|
RunnableAdapter(Runnable task, T result) {
|
436 |
|
|
this.task = task;
|
437 |
|
|
this.result = result;
|
438 |
|
|
}
|
439 |
|
|
public T call() {
|
440 |
|
|
task.run();
|
441 |
|
|
return result;
|
442 |
|
|
}
|
443 |
|
|
}
|
444 |
|
|
|
445 |
|
|
/**
|
446 |
|
|
* A callable that runs under established access control settings
|
447 |
|
|
*/
|
448 |
|
|
static final class PrivilegedCallable<T> implements Callable<T> {
|
449 |
|
|
private final AccessControlContext acc;
|
450 |
|
|
private final Callable<T> task;
|
451 |
|
|
private T result;
|
452 |
|
|
private Exception exception;
|
453 |
|
|
PrivilegedCallable(Callable<T> task) {
|
454 |
|
|
this.task = task;
|
455 |
|
|
this.acc = AccessController.getContext();
|
456 |
|
|
}
|
457 |
|
|
|
458 |
|
|
public T call() throws Exception {
|
459 |
|
|
AccessController.doPrivileged(new PrivilegedAction<T>() {
|
460 |
|
|
public T run() {
|
461 |
|
|
try {
|
462 |
|
|
result = task.call();
|
463 |
|
|
} catch (Exception ex) {
|
464 |
|
|
exception = ex;
|
465 |
|
|
}
|
466 |
|
|
return null;
|
467 |
|
|
}
|
468 |
|
|
}, acc);
|
469 |
|
|
if (exception != null)
|
470 |
|
|
throw exception;
|
471 |
|
|
else
|
472 |
|
|
return result;
|
473 |
|
|
}
|
474 |
|
|
}
|
475 |
|
|
|
476 |
|
|
/**
|
477 |
|
|
* A callable that runs under established access control settings and
|
478 |
|
|
* current ClassLoader
|
479 |
|
|
*/
|
480 |
|
|
static final class PrivilegedCallableUsingCurrentClassLoader<T> implements Callable<T> {
|
481 |
|
|
private final ClassLoader ccl;
|
482 |
|
|
private final AccessControlContext acc;
|
483 |
|
|
private final Callable<T> task;
|
484 |
|
|
private T result;
|
485 |
|
|
private Exception exception;
|
486 |
|
|
PrivilegedCallableUsingCurrentClassLoader(Callable<T> task) {
|
487 |
|
|
this.task = task;
|
488 |
|
|
this.ccl = Thread.currentThread().getContextClassLoader();
|
489 |
|
|
this.acc = AccessController.getContext();
|
490 |
|
|
acc.checkPermission(new RuntimePermission("getContextClassLoader"));
|
491 |
|
|
acc.checkPermission(new RuntimePermission("setContextClassLoader"));
|
492 |
|
|
}
|
493 |
|
|
|
494 |
|
|
public T call() throws Exception {
|
495 |
|
|
AccessController.doPrivileged(new PrivilegedAction<T>() {
|
496 |
|
|
public T run() {
|
497 |
|
|
ClassLoader savedcl = null;
|
498 |
|
|
Thread t = Thread.currentThread();
|
499 |
|
|
try {
|
500 |
|
|
ClassLoader cl = t.getContextClassLoader();
|
501 |
|
|
if (ccl != cl) {
|
502 |
|
|
t.setContextClassLoader(ccl);
|
503 |
|
|
savedcl = cl;
|
504 |
|
|
}
|
505 |
|
|
result = task.call();
|
506 |
|
|
} catch (Exception ex) {
|
507 |
|
|
exception = ex;
|
508 |
|
|
} finally {
|
509 |
|
|
if (savedcl != null)
|
510 |
|
|
t.setContextClassLoader(savedcl);
|
511 |
|
|
}
|
512 |
|
|
return null;
|
513 |
|
|
}
|
514 |
|
|
}, acc);
|
515 |
|
|
if (exception != null)
|
516 |
|
|
throw exception;
|
517 |
|
|
else
|
518 |
|
|
return result;
|
519 |
|
|
}
|
520 |
|
|
}
|
521 |
|
|
|
522 |
|
|
/**
|
523 |
|
|
* The default thread factory
|
524 |
|
|
*/
|
525 |
|
|
static class DefaultThreadFactory implements ThreadFactory {
|
526 |
|
|
static final AtomicInteger poolNumber = new AtomicInteger(1);
|
527 |
|
|
final ThreadGroup group;
|
528 |
|
|
final AtomicInteger threadNumber = new AtomicInteger(1);
|
529 |
|
|
final String namePrefix;
|
530 |
|
|
|
531 |
|
|
DefaultThreadFactory() {
|
532 |
|
|
SecurityManager s = System.getSecurityManager();
|
533 |
|
|
group = (s != null)? s.getThreadGroup() :
|
534 |
|
|
Thread.currentThread().getThreadGroup();
|
535 |
|
|
namePrefix = "pool-" +
|
536 |
|
|
poolNumber.getAndIncrement() +
|
537 |
|
|
"-thread-";
|
538 |
|
|
}
|
539 |
|
|
|
540 |
|
|
public Thread newThread(Runnable r) {
|
541 |
|
|
Thread t = new Thread(group, r,
|
542 |
|
|
namePrefix + threadNumber.getAndIncrement(),
|
543 |
|
|
0);
|
544 |
|
|
if (t.isDaemon())
|
545 |
|
|
t.setDaemon(false);
|
546 |
|
|
if (t.getPriority() != Thread.NORM_PRIORITY)
|
547 |
|
|
t.setPriority(Thread.NORM_PRIORITY);
|
548 |
|
|
return t;
|
549 |
|
|
}
|
550 |
|
|
}
|
551 |
|
|
|
552 |
|
|
/**
|
553 |
|
|
* Thread factory capturing access control and class loader
|
554 |
|
|
*/
|
555 |
|
|
static class PrivilegedThreadFactory extends DefaultThreadFactory {
|
556 |
|
|
private final ClassLoader ccl;
|
557 |
|
|
private final AccessControlContext acc;
|
558 |
|
|
|
559 |
|
|
PrivilegedThreadFactory() {
|
560 |
|
|
super();
|
561 |
|
|
this.ccl = Thread.currentThread().getContextClassLoader();
|
562 |
|
|
this.acc = AccessController.getContext();
|
563 |
|
|
acc.checkPermission(new RuntimePermission("setContextClassLoader"));
|
564 |
|
|
}
|
565 |
|
|
|
566 |
|
|
public Thread newThread(final Runnable r) {
|
567 |
|
|
return super.newThread(new Runnable() {
|
568 |
|
|
public void run() {
|
569 |
|
|
AccessController.doPrivileged(new PrivilegedAction<Object>() {
|
570 |
|
|
public Object run() {
|
571 |
|
|
Thread.currentThread().setContextClassLoader(ccl);
|
572 |
|
|
r.run();
|
573 |
|
|
return null;
|
574 |
|
|
}
|
575 |
|
|
}, acc);
|
576 |
|
|
}
|
577 |
|
|
});
|
578 |
|
|
}
|
579 |
|
|
|
580 |
|
|
}
|
581 |
|
|
|
582 |
|
|
/**
|
583 |
|
|
* A wrapper class that exposes only the ExecutorService methods
|
584 |
|
|
* of an ExecutorService implementation.
|
585 |
|
|
*/
|
586 |
|
|
static class DelegatedExecutorService extends AbstractExecutorService {
|
587 |
|
|
private final ExecutorService e;
|
588 |
|
|
DelegatedExecutorService(ExecutorService executor) { e = executor; }
|
589 |
|
|
public void execute(Runnable command) { e.execute(command); }
|
590 |
|
|
public void shutdown() { e.shutdown(); }
|
591 |
|
|
public List<Runnable> shutdownNow() { return e.shutdownNow(); }
|
592 |
|
|
public boolean isShutdown() { return e.isShutdown(); }
|
593 |
|
|
public boolean isTerminated() { return e.isTerminated(); }
|
594 |
|
|
public boolean awaitTermination(long timeout, TimeUnit unit)
|
595 |
|
|
throws InterruptedException {
|
596 |
|
|
return e.awaitTermination(timeout, unit);
|
597 |
|
|
}
|
598 |
|
|
public Future<?> submit(Runnable task) {
|
599 |
|
|
return e.submit(task);
|
600 |
|
|
}
|
601 |
|
|
public <T> Future<T> submit(Callable<T> task) {
|
602 |
|
|
return e.submit(task);
|
603 |
|
|
}
|
604 |
|
|
public <T> Future<T> submit(Runnable task, T result) {
|
605 |
|
|
return e.submit(task, result);
|
606 |
|
|
}
|
607 |
|
|
public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
|
608 |
|
|
throws InterruptedException {
|
609 |
|
|
return e.invokeAll(tasks);
|
610 |
|
|
}
|
611 |
|
|
public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks,
|
612 |
|
|
long timeout, TimeUnit unit)
|
613 |
|
|
throws InterruptedException {
|
614 |
|
|
return e.invokeAll(tasks, timeout, unit);
|
615 |
|
|
}
|
616 |
|
|
public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
|
617 |
|
|
throws InterruptedException, ExecutionException {
|
618 |
|
|
return e.invokeAny(tasks);
|
619 |
|
|
}
|
620 |
|
|
public <T> T invokeAny(Collection<? extends Callable<T>> tasks,
|
621 |
|
|
long timeout, TimeUnit unit)
|
622 |
|
|
throws InterruptedException, ExecutionException, TimeoutException {
|
623 |
|
|
return e.invokeAny(tasks, timeout, unit);
|
624 |
|
|
}
|
625 |
|
|
}
|
626 |
|
|
|
627 |
|
|
static class FinalizableDelegatedExecutorService
|
628 |
|
|
extends DelegatedExecutorService {
|
629 |
|
|
FinalizableDelegatedExecutorService(ExecutorService executor) {
|
630 |
|
|
super(executor);
|
631 |
|
|
}
|
632 |
|
|
protected void finalize() {
|
633 |
|
|
super.shutdown();
|
634 |
|
|
}
|
635 |
|
|
}
|
636 |
|
|
|
637 |
|
|
/**
|
638 |
|
|
* A wrapper class that exposes only the ScheduledExecutorService
|
639 |
|
|
* methods of a ScheduledExecutorService implementation.
|
640 |
|
|
*/
|
641 |
|
|
static class DelegatedScheduledExecutorService
|
642 |
|
|
extends DelegatedExecutorService
|
643 |
|
|
implements ScheduledExecutorService {
|
644 |
|
|
private final ScheduledExecutorService e;
|
645 |
|
|
DelegatedScheduledExecutorService(ScheduledExecutorService executor) {
|
646 |
|
|
super(executor);
|
647 |
|
|
e = executor;
|
648 |
|
|
}
|
649 |
|
|
public ScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
|
650 |
|
|
return e.schedule(command, delay, unit);
|
651 |
|
|
}
|
652 |
|
|
public <V> ScheduledFuture<V> schedule(Callable<V> callable, long delay, TimeUnit unit) {
|
653 |
|
|
return e.schedule(callable, delay, unit);
|
654 |
|
|
}
|
655 |
|
|
public ScheduledFuture<?> scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit) {
|
656 |
|
|
return e.scheduleAtFixedRate(command, initialDelay, period, unit);
|
657 |
|
|
}
|
658 |
|
|
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit) {
|
659 |
|
|
return e.scheduleWithFixedDelay(command, initialDelay, delay, unit);
|
660 |
|
|
}
|
661 |
|
|
}
|
662 |
|
|
|
663 |
|
|
|
664 |
|
|
/** Cannot instantiate. */
|
665 |
|
|
private Executors() {}
|
666 |
|
|
}
|