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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/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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/** |
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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 set 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. If |
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* additional tasks are submitted when all threads are active, |
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* they will wait in the queue until a thread is available. If |
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* any thread terminates due to a failure during execution prior |
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* to shutdown, a new one will take its place if needed to execute |
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* subsequent tasks. |
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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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*/ |
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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 set 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. |
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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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*/ |
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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 DelegatedExecutorService |
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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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*/ |
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public static ExecutorService newSingleThreadExecutor(ThreadFactory threadFactory) { |
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return new DelegatedExecutorService |
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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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*/ |
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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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/** |
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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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*/ |
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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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/** |
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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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*/ |
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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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/** |
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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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*/ |
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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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/** |
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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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/** |
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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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1.54 |
* 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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1.22 |
* 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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1.23 |
* {@link AccessController#doPrivileged} action setting the |
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1.24 |
* current thread's access control context to create threads with |
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1.23 |
* the selected permission settings holding within that action. |
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1.22 |
* |
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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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1.26 |
return new PrivilegedThreadFactory(); |
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} |
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|
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/** |
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1.43 |
* 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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* @throws NullPointerException if task null |
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1.43 |
* @return a callable object |
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*/ |
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public static <T> Callable<T> callable(Runnable task, T result) { |
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1.42 |
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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/** |
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* Returns a {@link Callable} object that, when |
331 |
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* called, runs the given task and returns <tt>null</tt>. |
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1.38 |
* @param task the task to run |
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* @return a callable object |
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1.42 |
* @throws NullPointerException if task null |
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1.38 |
*/ |
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public static Callable<Object> callable(Runnable task) { |
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1.42 |
if (task == null) |
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throw new NullPointerException(); |
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1.38 |
return new RunnableAdapter<Object>(task, null); |
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} |
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/** |
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tim |
1.43 |
* Returns a {@link Callable} object that, when |
344 |
dl |
1.49 |
* called, runs the given privileged action and returns its result. |
345 |
dl |
1.38 |
* @param action the privileged action to run |
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tim |
1.43 |
* @return a callable object |
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dl |
1.42 |
* @throws NullPointerException if action null |
348 |
dl |
1.38 |
*/ |
349 |
dl |
1.56 |
public static Callable<Object> callable(final PrivilegedAction<?> action) { |
350 |
dl |
1.42 |
if (action == null) |
351 |
|
|
throw new NullPointerException(); |
352 |
dl |
1.56 |
return new Callable<Object>() { |
353 |
|
|
public Object call() { return action.run(); }}; |
354 |
dl |
1.38 |
} |
355 |
|
|
|
356 |
|
|
/** |
357 |
tim |
1.43 |
* Returns a {@link Callable} object that, when |
358 |
dl |
1.39 |
* called, runs the given privileged exception action and returns |
359 |
dl |
1.49 |
* its result. |
360 |
dl |
1.38 |
* @param action the privileged exception action to run |
361 |
tim |
1.43 |
* @return a callable object |
362 |
dl |
1.42 |
* @throws NullPointerException if action null |
363 |
dl |
1.38 |
*/ |
364 |
dl |
1.56 |
public static Callable<Object> callable(final PrivilegedExceptionAction<?> action) { |
365 |
dl |
1.42 |
if (action == null) |
366 |
|
|
throw new NullPointerException(); |
367 |
dl |
1.56 |
return new Callable<Object>() { |
368 |
|
|
public Object call() throws Exception { return action.run(); }}; |
369 |
dl |
1.38 |
} |
370 |
|
|
|
371 |
|
|
/** |
372 |
tim |
1.43 |
* Returns a {@link Callable} object that will, when |
373 |
dl |
1.39 |
* called, execute the given <tt>callable</tt> under the current |
374 |
|
|
* access control context. This method should normally be |
375 |
|
|
* invoked within an {@link AccessController#doPrivileged} action |
376 |
|
|
* to create callables that will, if possible, execute under the |
377 |
|
|
* selected permission settings holding within that action; or if |
378 |
|
|
* not possible, throw an associated {@link |
379 |
|
|
* AccessControlException}. |
380 |
|
|
* @param callable the underlying task |
381 |
tim |
1.43 |
* @return a callable object |
382 |
dl |
1.42 |
* @throws NullPointerException if callable null |
383 |
dl |
1.39 |
* |
384 |
|
|
*/ |
385 |
|
|
public static <T> Callable<T> privilegedCallable(Callable<T> callable) { |
386 |
dl |
1.42 |
if (callable == null) |
387 |
|
|
throw new NullPointerException(); |
388 |
dl |
1.55 |
return new PrivilegedCallable<T>(callable); |
389 |
dl |
1.39 |
} |
390 |
jsr166 |
1.52 |
|
391 |
dl |
1.39 |
/** |
392 |
tim |
1.43 |
* Returns a {@link Callable} object that will, when |
393 |
dl |
1.39 |
* called, execute the given <tt>callable</tt> under the current |
394 |
|
|
* access control context, with the current context class loader |
395 |
|
|
* as the context class loader. This method should normally be |
396 |
|
|
* invoked within an {@link AccessController#doPrivileged} action |
397 |
|
|
* to create callables that will, if possible, execute under the |
398 |
|
|
* selected permission settings holding within that action; or if |
399 |
|
|
* not possible, throw an associated {@link |
400 |
|
|
* AccessControlException}. |
401 |
|
|
* @param callable the underlying task |
402 |
|
|
* |
403 |
tim |
1.43 |
* @return a callable object |
404 |
dl |
1.42 |
* @throws NullPointerException if callable null |
405 |
dl |
1.39 |
* @throws AccessControlException if the current access control |
406 |
|
|
* context does not have permission to both set and get context |
407 |
|
|
* class loader. |
408 |
|
|
*/ |
409 |
|
|
public static <T> Callable<T> privilegedCallableUsingCurrentClassLoader(Callable<T> callable) { |
410 |
dl |
1.42 |
if (callable == null) |
411 |
|
|
throw new NullPointerException(); |
412 |
dl |
1.55 |
return new PrivilegedCallableUsingCurrentClassLoader<T>(callable); |
413 |
dl |
1.39 |
} |
414 |
|
|
|
415 |
dl |
1.40 |
// Non-public classes supporting the public methods |
416 |
dl |
1.39 |
|
417 |
|
|
/** |
418 |
dl |
1.38 |
* A callable that runs given task and returns given result |
419 |
|
|
*/ |
420 |
dl |
1.48 |
static final class RunnableAdapter<T> implements Callable<T> { |
421 |
|
|
final Runnable task; |
422 |
|
|
final T result; |
423 |
dl |
1.38 |
RunnableAdapter(Runnable task, T result) { |
424 |
jsr166 |
1.52 |
this.task = task; |
425 |
dl |
1.38 |
this.result = result; |
426 |
|
|
} |
427 |
jsr166 |
1.52 |
public T call() { |
428 |
|
|
task.run(); |
429 |
|
|
return result; |
430 |
dl |
1.38 |
} |
431 |
|
|
} |
432 |
|
|
|
433 |
|
|
/** |
434 |
dl |
1.39 |
* A callable that runs under established access control settings |
435 |
|
|
*/ |
436 |
dl |
1.48 |
static final class PrivilegedCallable<T> implements Callable<T> { |
437 |
dl |
1.39 |
private final AccessControlContext acc; |
438 |
|
|
private final Callable<T> task; |
439 |
dl |
1.40 |
private T result; |
440 |
|
|
private Exception exception; |
441 |
dl |
1.39 |
PrivilegedCallable(Callable<T> task) { |
442 |
|
|
this.task = task; |
443 |
|
|
this.acc = AccessController.getContext(); |
444 |
|
|
} |
445 |
|
|
|
446 |
|
|
public T call() throws Exception { |
447 |
dl |
1.55 |
AccessController.doPrivileged(new PrivilegedAction<T>() { |
448 |
|
|
public T run() { |
449 |
dl |
1.39 |
try { |
450 |
|
|
result = task.call(); |
451 |
jsr166 |
1.51 |
} catch (Exception ex) { |
452 |
dl |
1.39 |
exception = ex; |
453 |
|
|
} |
454 |
|
|
return null; |
455 |
|
|
} |
456 |
|
|
}, acc); |
457 |
|
|
if (exception != null) |
458 |
|
|
throw exception; |
459 |
jsr166 |
1.52 |
else |
460 |
dl |
1.39 |
return result; |
461 |
|
|
} |
462 |
|
|
} |
463 |
|
|
|
464 |
|
|
/** |
465 |
|
|
* A callable that runs under established access control settings and |
466 |
|
|
* current ClassLoader |
467 |
|
|
*/ |
468 |
dl |
1.48 |
static final class PrivilegedCallableUsingCurrentClassLoader<T> implements Callable<T> { |
469 |
dl |
1.39 |
private final ClassLoader ccl; |
470 |
|
|
private final AccessControlContext acc; |
471 |
|
|
private final Callable<T> task; |
472 |
dl |
1.40 |
private T result; |
473 |
|
|
private Exception exception; |
474 |
dl |
1.39 |
PrivilegedCallableUsingCurrentClassLoader(Callable<T> task) { |
475 |
|
|
this.task = task; |
476 |
|
|
this.ccl = Thread.currentThread().getContextClassLoader(); |
477 |
|
|
this.acc = AccessController.getContext(); |
478 |
|
|
acc.checkPermission(new RuntimePermission("getContextClassLoader")); |
479 |
|
|
acc.checkPermission(new RuntimePermission("setContextClassLoader")); |
480 |
|
|
} |
481 |
|
|
|
482 |
|
|
public T call() throws Exception { |
483 |
dl |
1.55 |
AccessController.doPrivileged(new PrivilegedAction<T>() { |
484 |
|
|
public T run() { |
485 |
dl |
1.39 |
ClassLoader savedcl = null; |
486 |
|
|
Thread t = Thread.currentThread(); |
487 |
|
|
try { |
488 |
|
|
ClassLoader cl = t.getContextClassLoader(); |
489 |
|
|
if (ccl != cl) { |
490 |
|
|
t.setContextClassLoader(ccl); |
491 |
|
|
savedcl = cl; |
492 |
|
|
} |
493 |
|
|
result = task.call(); |
494 |
jsr166 |
1.51 |
} catch (Exception ex) { |
495 |
dl |
1.39 |
exception = ex; |
496 |
|
|
} finally { |
497 |
|
|
if (savedcl != null) |
498 |
|
|
t.setContextClassLoader(savedcl); |
499 |
|
|
} |
500 |
|
|
return null; |
501 |
|
|
} |
502 |
|
|
}, acc); |
503 |
|
|
if (exception != null) |
504 |
|
|
throw exception; |
505 |
jsr166 |
1.52 |
else |
506 |
dl |
1.39 |
return result; |
507 |
|
|
} |
508 |
|
|
} |
509 |
|
|
|
510 |
dl |
1.40 |
/** |
511 |
|
|
* The default thread factory |
512 |
|
|
*/ |
513 |
dl |
1.48 |
static class DefaultThreadFactory implements ThreadFactory { |
514 |
tim |
1.26 |
static final AtomicInteger poolNumber = new AtomicInteger(1); |
515 |
|
|
final ThreadGroup group; |
516 |
|
|
final AtomicInteger threadNumber = new AtomicInteger(1); |
517 |
|
|
final String namePrefix; |
518 |
dl |
1.22 |
|
519 |
tim |
1.26 |
DefaultThreadFactory() { |
520 |
dl |
1.22 |
SecurityManager s = System.getSecurityManager(); |
521 |
|
|
group = (s != null)? s.getThreadGroup() : |
522 |
|
|
Thread.currentThread().getThreadGroup(); |
523 |
jsr166 |
1.52 |
namePrefix = "pool-" + |
524 |
|
|
poolNumber.getAndIncrement() + |
525 |
dl |
1.22 |
"-thread-"; |
526 |
|
|
} |
527 |
|
|
|
528 |
|
|
public Thread newThread(Runnable r) { |
529 |
jsr166 |
1.52 |
Thread t = new Thread(group, r, |
530 |
dl |
1.22 |
namePrefix + threadNumber.getAndIncrement(), |
531 |
|
|
0); |
532 |
|
|
if (t.isDaemon()) |
533 |
|
|
t.setDaemon(false); |
534 |
|
|
if (t.getPriority() != Thread.NORM_PRIORITY) |
535 |
|
|
t.setPriority(Thread.NORM_PRIORITY); |
536 |
|
|
return t; |
537 |
|
|
} |
538 |
|
|
} |
539 |
|
|
|
540 |
dl |
1.40 |
/** |
541 |
|
|
* Thread factory capturing access control and class loader |
542 |
|
|
*/ |
543 |
dl |
1.48 |
static class PrivilegedThreadFactory extends DefaultThreadFactory { |
544 |
dl |
1.22 |
private final ClassLoader ccl; |
545 |
|
|
private final AccessControlContext acc; |
546 |
|
|
|
547 |
|
|
PrivilegedThreadFactory() { |
548 |
|
|
super(); |
549 |
|
|
this.ccl = Thread.currentThread().getContextClassLoader(); |
550 |
|
|
this.acc = AccessController.getContext(); |
551 |
|
|
acc.checkPermission(new RuntimePermission("setContextClassLoader")); |
552 |
|
|
} |
553 |
jsr166 |
1.52 |
|
554 |
dl |
1.22 |
public Thread newThread(final Runnable r) { |
555 |
|
|
return super.newThread(new Runnable() { |
556 |
|
|
public void run() { |
557 |
dl |
1.55 |
AccessController.doPrivileged(new PrivilegedAction<Object>() { |
558 |
jsr166 |
1.52 |
public Object run() { |
559 |
dl |
1.22 |
Thread.currentThread().setContextClassLoader(ccl); |
560 |
|
|
r.run(); |
561 |
jsr166 |
1.52 |
return null; |
562 |
dl |
1.22 |
} |
563 |
|
|
}, acc); |
564 |
|
|
} |
565 |
|
|
}); |
566 |
|
|
} |
567 |
jsr166 |
1.52 |
|
568 |
dl |
1.36 |
} |
569 |
|
|
|
570 |
|
|
/** |
571 |
|
|
* A wrapper class that exposes only the ExecutorService methods |
572 |
|
|
* of an implementation. |
573 |
|
|
*/ |
574 |
dl |
1.48 |
static class DelegatedExecutorService extends AbstractExecutorService { |
575 |
dl |
1.36 |
private final ExecutorService e; |
576 |
|
|
DelegatedExecutorService(ExecutorService executor) { e = executor; } |
577 |
|
|
public void execute(Runnable command) { e.execute(command); } |
578 |
|
|
public void shutdown() { e.shutdown(); } |
579 |
|
|
public List<Runnable> shutdownNow() { return e.shutdownNow(); } |
580 |
|
|
public boolean isShutdown() { return e.isShutdown(); } |
581 |
|
|
public boolean isTerminated() { return e.isTerminated(); } |
582 |
|
|
public boolean awaitTermination(long timeout, TimeUnit unit) |
583 |
|
|
throws InterruptedException { |
584 |
|
|
return e.awaitTermination(timeout, unit); |
585 |
|
|
} |
586 |
dl |
1.38 |
public Future<?> submit(Runnable task) { |
587 |
|
|
return e.submit(task); |
588 |
dl |
1.36 |
} |
589 |
|
|
public <T> Future<T> submit(Callable<T> task) { |
590 |
|
|
return e.submit(task); |
591 |
|
|
} |
592 |
dl |
1.41 |
public <T> Future<T> submit(Runnable task, T result) { |
593 |
|
|
return e.submit(task, result); |
594 |
|
|
} |
595 |
|
|
public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks) |
596 |
dl |
1.36 |
throws InterruptedException { |
597 |
|
|
return e.invokeAll(tasks); |
598 |
|
|
} |
599 |
jsr166 |
1.52 |
public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks, |
600 |
|
|
long timeout, TimeUnit unit) |
601 |
dl |
1.36 |
throws InterruptedException { |
602 |
|
|
return e.invokeAll(tasks, timeout, unit); |
603 |
|
|
} |
604 |
|
|
public <T> T invokeAny(Collection<Callable<T>> tasks) |
605 |
|
|
throws InterruptedException, ExecutionException { |
606 |
|
|
return e.invokeAny(tasks); |
607 |
|
|
} |
608 |
jsr166 |
1.52 |
public <T> T invokeAny(Collection<Callable<T>> tasks, |
609 |
|
|
long timeout, TimeUnit unit) |
610 |
dl |
1.36 |
throws InterruptedException, ExecutionException, TimeoutException { |
611 |
|
|
return e.invokeAny(tasks, timeout, unit); |
612 |
|
|
} |
613 |
|
|
} |
614 |
jsr166 |
1.52 |
|
615 |
dl |
1.36 |
/** |
616 |
jsr166 |
1.52 |
* A wrapper class that exposes only the ExecutorService and |
617 |
tim |
1.43 |
* ScheduleExecutor methods of a ScheduledExecutorService implementation. |
618 |
dl |
1.36 |
*/ |
619 |
dl |
1.48 |
static class DelegatedScheduledExecutorService |
620 |
jsr166 |
1.52 |
extends DelegatedExecutorService |
621 |
dl |
1.36 |
implements ScheduledExecutorService { |
622 |
|
|
private final ScheduledExecutorService e; |
623 |
|
|
DelegatedScheduledExecutorService(ScheduledExecutorService executor) { |
624 |
|
|
super(executor); |
625 |
|
|
e = executor; |
626 |
|
|
} |
627 |
|
|
public ScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) { |
628 |
|
|
return e.schedule(command, delay, unit); |
629 |
|
|
} |
630 |
|
|
public <V> ScheduledFuture<V> schedule(Callable<V> callable, long delay, TimeUnit unit) { |
631 |
|
|
return e.schedule(callable, delay, unit); |
632 |
|
|
} |
633 |
|
|
public ScheduledFuture<?> scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit) { |
634 |
|
|
return e.scheduleAtFixedRate(command, initialDelay, period, unit); |
635 |
|
|
} |
636 |
|
|
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit) { |
637 |
|
|
return e.scheduleWithFixedDelay(command, initialDelay, delay, unit); |
638 |
|
|
} |
639 |
dl |
1.22 |
} |
640 |
|
|
|
641 |
jsr166 |
1.52 |
|
642 |
tim |
1.15 |
/** Cannot instantiate. */ |
643 |
|
|
private Executors() {} |
644 |
tim |
1.1 |
} |