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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.concurrent.atomic.*;
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import java.util.*;
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/**
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* A {@link ThreadPoolExecutor} that can additionally schedule
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* commands to run after a given delay, or to execute
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* periodically. This class is preferable to {@link java.util.Timer}
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* when multiple worker threads are needed, or when the additional
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* flexibility or capabilities of {@link ThreadPoolExecutor} (which
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* this class extends) are required.
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*
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* <p> Delayed tasks execute no sooner than they are enabled, but
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* without any real-time guarantees about when, after they are
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* enabled, they will commence. Tasks scheduled for exactly the same
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* execution time are enabled in first-in-first-out (FIFO) order of
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* submission.
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*
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* <p>While this class inherits from {@link ThreadPoolExecutor}, a few
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* of the inherited tuning methods are not useful for it. In
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* particular, because it acts as a fixed-sized pool using
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* <tt>corePoolSize</tt> threads and an unbounded queue, adjustments
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* to <tt>maximumPoolSize</tt> have no useful effect.
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*
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* <p><b>Extension notes:</b> This class overrides {@link
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* AbstractExecutorService} <tt>submit</tt> methods to generate
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* internal objects to control per-task delays and scheduling. To
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* preserve functionality, any further overrides of these methods in
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* subclasses must invoke superclass versions, which effectively
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* disables additional task customization. However, this class
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* provides alternative protected extension method
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* <tt>decorateTask</tt> (one version each for <tt>Runnable</tt> and
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* <tt>Callable</tt>) that can be used to customize the concrete task
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* types used to execute commands entered via <tt>execute</tt>,
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* <tt>submit</tt>, <tt>schedule</tt>, <tt>scheduleAtFixedRate</tt>,
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* and <tt>scheduleWithFixedDelay</tt>. By default, a
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* <tt>ScheduledThreadPoolExecutor</tt> uses a task type extending
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* {@link FutureTask}. However, this may be modified or replaced using
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* subclasses of the form:
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*
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* <pre>
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* public class CustomScheduledExecutor extends ScheduledThreadPoolExecutor {
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*
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* static class CustomTask<V> implements RunnableScheduledFuture<V> { ... }
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*
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* protected <V> RunnableScheduledFuture<V> decorateTask(
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* Runnable r, RunnableScheduledFuture<V> task) {
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* return new CustomTask<V>(r, task);
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* }
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*
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* protected <V> RunnableScheduledFuture<V> decorateTask(
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* Callable<V> c, RunnableScheduledFuture<V> task) {
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* return new CustomTask<V>(c, task);
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* }
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* // ... add constructors, etc.
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* }
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* </pre>
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* @since 1.5
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* @author Doug Lea
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*/
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public class ScheduledThreadPoolExecutor
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extends ThreadPoolExecutor
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implements ScheduledExecutorService {
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/**
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* False if should cancel/suppress periodic tasks on shutdown.
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*/
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private volatile boolean continueExistingPeriodicTasksAfterShutdown;
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/**
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* False if should cancel non-periodic tasks on shutdown.
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*/
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private volatile boolean executeExistingDelayedTasksAfterShutdown = true;
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/**
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* Sequence number to break scheduling ties, and in turn to
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* guarantee FIFO order among tied entries.
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*/
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private static final AtomicLong sequencer = new AtomicLong(0);
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/** Base of nanosecond timings, to avoid wrapping */
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private static final long NANO_ORIGIN = System.nanoTime();
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/**
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* Returns nanosecond time offset by origin
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*/
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final long now() {
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return System.nanoTime() - NANO_ORIGIN;
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}
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private class ScheduledFutureTask<V>
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extends FutureTask<V> implements RunnableScheduledFuture<V> {
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/** Sequence number to break ties FIFO */
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private final long sequenceNumber;
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/** The time the task is enabled to execute in nanoTime units */
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private long time;
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/**
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* Period in nanoseconds for repeating tasks. A positive
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* value indicates fixed-rate execution. A negative value
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* indicates fixed-delay execution. A value of 0 indicates a
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* non-repeating task.
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*/
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private final long period;
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/**
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* Creates a one-shot action with given nanoTime-based trigger time.
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*/
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ScheduledFutureTask(Runnable r, V result, long ns) {
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super(r, result);
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this.time = ns;
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this.period = 0;
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this.sequenceNumber = sequencer.getAndIncrement();
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}
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/**
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* Creates a periodic action with given nano time and period.
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*/
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ScheduledFutureTask(Runnable r, V result, long ns, long period) {
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super(r, result);
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this.time = ns;
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this.period = period;
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this.sequenceNumber = sequencer.getAndIncrement();
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}
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/**
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* Creates a one-shot action with given nanoTime-based trigger.
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*/
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ScheduledFutureTask(Callable<V> callable, long ns) {
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super(callable);
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this.time = ns;
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this.period = 0;
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this.sequenceNumber = sequencer.getAndIncrement();
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}
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public long getDelay(TimeUnit unit) {
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long d = unit.convert(time - now(), TimeUnit.NANOSECONDS);
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return d;
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}
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public int compareTo(Delayed other) {
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if (other == this) // compare zero ONLY if same object
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return 0;
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if (other instanceof ScheduledFutureTask) {
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ScheduledFutureTask<?> x = (ScheduledFutureTask<?>)other;
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long diff = time - x.time;
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if (diff < 0)
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return -1;
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else if (diff > 0)
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return 1;
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else if (sequenceNumber < x.sequenceNumber)
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return -1;
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else
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return 1;
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}
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long d = (getDelay(TimeUnit.NANOSECONDS) -
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other.getDelay(TimeUnit.NANOSECONDS));
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return (d == 0)? 0 : ((d < 0)? -1 : 1);
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}
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/**
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* Returns true if this is a periodic (not a one-shot) action.
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*
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* @return true if periodic
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*/
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public boolean isPeriodic() {
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return period != 0;
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}
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/**
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* Runs a periodic task.
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*/
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private void runPeriodic() {
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boolean ok = ScheduledFutureTask.super.runAndReset();
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boolean down = isShutdown();
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// Reschedule if not cancelled and not shutdown or policy allows
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if (ok && (!down ||
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(getContinueExistingPeriodicTasksAfterShutdownPolicy() &&
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!isTerminating()))) {
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long p = period;
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if (p > 0)
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time += p;
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else
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time = now() - p;
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// Classpath local: ecj from eclipse 3.1 does not
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// compile this.
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// ScheduledThreadPoolExecutor.super.getQueue().add(this);
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ScheduledThreadPoolExecutor.super.getQueue().add((Runnable) this);
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}
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// This might have been the final executed delayed
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// task. Wake up threads to check.
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else if (down)
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interruptIdleWorkers();
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}
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/**
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* Overrides FutureTask version so as to reset/requeue if periodic.
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*/
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public void run() {
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if (isPeriodic())
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runPeriodic();
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else
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ScheduledFutureTask.super.run();
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}
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}
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/**
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* Specialized variant of ThreadPoolExecutor.execute for delayed tasks.
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*/
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private void delayedExecute(Runnable command) {
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if (isShutdown()) {
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reject(command);
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return;
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}
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// Prestart a thread if necessary. We cannot prestart it
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// running the task because the task (probably) shouldn't be
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// run yet, so thread will just idle until delay elapses.
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if (getPoolSize() < getCorePoolSize())
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prestartCoreThread();
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super.getQueue().add(command);
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}
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/**
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* Cancels and clears the queue of all tasks that should not be run
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* due to shutdown policy.
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*/
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private void cancelUnwantedTasks() {
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boolean keepDelayed = getExecuteExistingDelayedTasksAfterShutdownPolicy();
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boolean keepPeriodic = getContinueExistingPeriodicTasksAfterShutdownPolicy();
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if (!keepDelayed && !keepPeriodic)
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super.getQueue().clear();
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else if (keepDelayed || keepPeriodic) {
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Object[] entries = super.getQueue().toArray();
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for (int i = 0; i < entries.length; ++i) {
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Object e = entries[i];
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if (e instanceof RunnableScheduledFuture) {
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RunnableScheduledFuture<?> t = (RunnableScheduledFuture<?>)e;
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if (t.isPeriodic()? !keepPeriodic : !keepDelayed)
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t.cancel(false);
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}
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}
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entries = null;
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purge();
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}
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}
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public boolean remove(Runnable task) {
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if (!(task instanceof RunnableScheduledFuture))
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return false;
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return getQueue().remove(task);
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}
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/**
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* Modifies or replaces the task used to execute a runnable.
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* This method can be used to override the concrete
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* class used for managing internal tasks.
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* The default implementation simply returns the given task.
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*
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* @param runnable the submitted Runnable
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* @param task the task created to execute the runnable
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* @return a task that can execute the runnable
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* @since 1.6
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*/
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protected <V> RunnableScheduledFuture<V> decorateTask(
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Runnable runnable, RunnableScheduledFuture<V> task) {
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return task;
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}
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/**
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* Modifies or replaces the task used to execute a callable.
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* This method can be used to override the concrete
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* class used for managing internal tasks.
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* The default implementation simply returns the given task.
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*
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* @param callable the submitted Callable
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* @param task the task created to execute the callable
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* @return a task that can execute the callable
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* @since 1.6
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*/
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protected <V> RunnableScheduledFuture<V> decorateTask(
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Callable<V> callable, RunnableScheduledFuture<V> task) {
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return task;
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}
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/**
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* Creates a new ScheduledThreadPoolExecutor with the given core
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* pool size.
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*
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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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* @throws IllegalArgumentException if <tt>corePoolSize < 0</tt>
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*/
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public ScheduledThreadPoolExecutor(int corePoolSize) {
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super(corePoolSize, Integer.MAX_VALUE, 0, TimeUnit.NANOSECONDS,
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new DelayedWorkQueue());
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}
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/**
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* Creates a new ScheduledThreadPoolExecutor with the given
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* initial parameters.
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*
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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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* @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 ScheduledThreadPoolExecutor(int corePoolSize,
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ThreadFactory threadFactory) {
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super(corePoolSize, Integer.MAX_VALUE, 0, TimeUnit.NANOSECONDS,
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new DelayedWorkQueue(), threadFactory);
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}
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|
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/**
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|
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* Creates a new ScheduledThreadPoolExecutor with the given
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* initial parameters.
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*
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|
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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 handler the handler to use when execution is blocked
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* because the thread bounds and queue capacities are reached
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* @throws IllegalArgumentException if <tt>corePoolSize < 0</tt>
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* @throws NullPointerException if handler is null
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*/
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public ScheduledThreadPoolExecutor(int corePoolSize,
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RejectedExecutionHandler handler) {
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super(corePoolSize, Integer.MAX_VALUE, 0, TimeUnit.NANOSECONDS,
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new DelayedWorkQueue(), handler);
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}
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|
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|
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/**
|
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|
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* Creates a new ScheduledThreadPoolExecutor with the given
|
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* initial parameters.
|
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*
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|
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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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* @param handler the handler to use when execution is blocked
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* because the thread bounds and queue capacities are reached.
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* @throws IllegalArgumentException if <tt>corePoolSize < 0</tt>
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|
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* @throws NullPointerException if threadFactory or handler is null
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*/
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352 |
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public ScheduledThreadPoolExecutor(int corePoolSize,
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ThreadFactory threadFactory,
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RejectedExecutionHandler handler) {
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super(corePoolSize, Integer.MAX_VALUE, 0, TimeUnit.NANOSECONDS,
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new DelayedWorkQueue(), threadFactory, handler);
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}
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|
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public ScheduledFuture<?> schedule(Runnable command,
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360 |
|
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long delay,
|
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TimeUnit unit) {
|
362 |
|
|
if (command == null || unit == null)
|
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|
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throw new NullPointerException();
|
364 |
|
|
long triggerTime = now() + unit.toNanos(delay);
|
365 |
|
|
RunnableScheduledFuture<?> t = decorateTask(command,
|
366 |
|
|
new ScheduledFutureTask<Boolean>(command, null, triggerTime));
|
367 |
|
|
delayedExecute(t);
|
368 |
|
|
return t;
|
369 |
|
|
}
|
370 |
|
|
|
371 |
|
|
public <V> ScheduledFuture<V> schedule(Callable<V> callable,
|
372 |
|
|
long delay,
|
373 |
|
|
TimeUnit unit) {
|
374 |
|
|
if (callable == null || unit == null)
|
375 |
|
|
throw new NullPointerException();
|
376 |
|
|
if (delay < 0) delay = 0;
|
377 |
|
|
long triggerTime = now() + unit.toNanos(delay);
|
378 |
|
|
RunnableScheduledFuture<V> t = decorateTask(callable,
|
379 |
|
|
new ScheduledFutureTask<V>(callable, triggerTime));
|
380 |
|
|
delayedExecute(t);
|
381 |
|
|
return t;
|
382 |
|
|
}
|
383 |
|
|
|
384 |
|
|
public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
|
385 |
|
|
long initialDelay,
|
386 |
|
|
long period,
|
387 |
|
|
TimeUnit unit) {
|
388 |
|
|
if (command == null || unit == null)
|
389 |
|
|
throw new NullPointerException();
|
390 |
|
|
if (period <= 0)
|
391 |
|
|
throw new IllegalArgumentException();
|
392 |
|
|
if (initialDelay < 0) initialDelay = 0;
|
393 |
|
|
long triggerTime = now() + unit.toNanos(initialDelay);
|
394 |
|
|
RunnableScheduledFuture<?> t = decorateTask(command,
|
395 |
|
|
new ScheduledFutureTask<Object>(command,
|
396 |
|
|
null,
|
397 |
|
|
triggerTime,
|
398 |
|
|
unit.toNanos(period)));
|
399 |
|
|
delayedExecute(t);
|
400 |
|
|
return t;
|
401 |
|
|
}
|
402 |
|
|
|
403 |
|
|
public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
|
404 |
|
|
long initialDelay,
|
405 |
|
|
long delay,
|
406 |
|
|
TimeUnit unit) {
|
407 |
|
|
if (command == null || unit == null)
|
408 |
|
|
throw new NullPointerException();
|
409 |
|
|
if (delay <= 0)
|
410 |
|
|
throw new IllegalArgumentException();
|
411 |
|
|
if (initialDelay < 0) initialDelay = 0;
|
412 |
|
|
long triggerTime = now() + unit.toNanos(initialDelay);
|
413 |
|
|
RunnableScheduledFuture<?> t = decorateTask(command,
|
414 |
|
|
new ScheduledFutureTask<Boolean>(command,
|
415 |
|
|
null,
|
416 |
|
|
triggerTime,
|
417 |
|
|
unit.toNanos(-delay)));
|
418 |
|
|
delayedExecute(t);
|
419 |
|
|
return t;
|
420 |
|
|
}
|
421 |
|
|
|
422 |
|
|
|
423 |
|
|
/**
|
424 |
|
|
* Executes command with zero required delay. This has effect
|
425 |
|
|
* equivalent to <tt>schedule(command, 0, anyUnit)</tt>. Note
|
426 |
|
|
* that inspections of the queue and of the list returned by
|
427 |
|
|
* <tt>shutdownNow</tt> will access the zero-delayed
|
428 |
|
|
* {@link ScheduledFuture}, not the <tt>command</tt> itself.
|
429 |
|
|
*
|
430 |
|
|
* @param command the task to execute
|
431 |
|
|
* @throws RejectedExecutionException at discretion of
|
432 |
|
|
* <tt>RejectedExecutionHandler</tt>, if task cannot be accepted
|
433 |
|
|
* for execution because the executor has been shut down.
|
434 |
|
|
* @throws NullPointerException if command is null
|
435 |
|
|
*/
|
436 |
|
|
public void execute(Runnable command) {
|
437 |
|
|
if (command == null)
|
438 |
|
|
throw new NullPointerException();
|
439 |
|
|
schedule(command, 0, TimeUnit.NANOSECONDS);
|
440 |
|
|
}
|
441 |
|
|
|
442 |
|
|
// Override AbstractExecutorService methods
|
443 |
|
|
|
444 |
|
|
public Future<?> submit(Runnable task) {
|
445 |
|
|
return schedule(task, 0, TimeUnit.NANOSECONDS);
|
446 |
|
|
}
|
447 |
|
|
|
448 |
|
|
public <T> Future<T> submit(Runnable task, T result) {
|
449 |
|
|
return schedule(Executors.callable(task, result),
|
450 |
|
|
0, TimeUnit.NANOSECONDS);
|
451 |
|
|
}
|
452 |
|
|
|
453 |
|
|
public <T> Future<T> submit(Callable<T> task) {
|
454 |
|
|
return schedule(task, 0, TimeUnit.NANOSECONDS);
|
455 |
|
|
}
|
456 |
|
|
|
457 |
|
|
/**
|
458 |
|
|
* Sets the policy on whether to continue executing existing periodic
|
459 |
|
|
* tasks even when this executor has been <tt>shutdown</tt>. In
|
460 |
|
|
* this case, these tasks will only terminate upon
|
461 |
|
|
* <tt>shutdownNow</tt>, or after setting the policy to
|
462 |
|
|
* <tt>false</tt> when already shutdown. This value is by default
|
463 |
|
|
* false.
|
464 |
|
|
*
|
465 |
|
|
* @param value if true, continue after shutdown, else don't.
|
466 |
|
|
* @see #getContinueExistingPeriodicTasksAfterShutdownPolicy
|
467 |
|
|
*/
|
468 |
|
|
public void setContinueExistingPeriodicTasksAfterShutdownPolicy(boolean value) {
|
469 |
|
|
continueExistingPeriodicTasksAfterShutdown = value;
|
470 |
|
|
if (!value && isShutdown())
|
471 |
|
|
cancelUnwantedTasks();
|
472 |
|
|
}
|
473 |
|
|
|
474 |
|
|
/**
|
475 |
|
|
* Gets the policy on whether to continue executing existing
|
476 |
|
|
* periodic tasks even when this executor has been
|
477 |
|
|
* <tt>shutdown</tt>. In this case, these tasks will only
|
478 |
|
|
* terminate upon <tt>shutdownNow</tt> or after setting the policy
|
479 |
|
|
* to <tt>false</tt> when already shutdown. This value is by
|
480 |
|
|
* default false.
|
481 |
|
|
*
|
482 |
|
|
* @return true if will continue after shutdown
|
483 |
|
|
* @see #setContinueExistingPeriodicTasksAfterShutdownPolicy
|
484 |
|
|
*/
|
485 |
|
|
public boolean getContinueExistingPeriodicTasksAfterShutdownPolicy() {
|
486 |
|
|
return continueExistingPeriodicTasksAfterShutdown;
|
487 |
|
|
}
|
488 |
|
|
|
489 |
|
|
/**
|
490 |
|
|
* Sets the policy on whether to execute existing delayed
|
491 |
|
|
* tasks even when this executor has been <tt>shutdown</tt>. In
|
492 |
|
|
* this case, these tasks will only terminate upon
|
493 |
|
|
* <tt>shutdownNow</tt>, or after setting the policy to
|
494 |
|
|
* <tt>false</tt> when already shutdown. This value is by default
|
495 |
|
|
* true.
|
496 |
|
|
*
|
497 |
|
|
* @param value if true, execute after shutdown, else don't.
|
498 |
|
|
* @see #getExecuteExistingDelayedTasksAfterShutdownPolicy
|
499 |
|
|
*/
|
500 |
|
|
public void setExecuteExistingDelayedTasksAfterShutdownPolicy(boolean value) {
|
501 |
|
|
executeExistingDelayedTasksAfterShutdown = value;
|
502 |
|
|
if (!value && isShutdown())
|
503 |
|
|
cancelUnwantedTasks();
|
504 |
|
|
}
|
505 |
|
|
|
506 |
|
|
/**
|
507 |
|
|
* Gets the policy on whether to execute existing delayed
|
508 |
|
|
* tasks even when this executor has been <tt>shutdown</tt>. In
|
509 |
|
|
* this case, these tasks will only terminate upon
|
510 |
|
|
* <tt>shutdownNow</tt>, or after setting the policy to
|
511 |
|
|
* <tt>false</tt> when already shutdown. This value is by default
|
512 |
|
|
* true.
|
513 |
|
|
*
|
514 |
|
|
* @return true if will execute after shutdown
|
515 |
|
|
* @see #setExecuteExistingDelayedTasksAfterShutdownPolicy
|
516 |
|
|
*/
|
517 |
|
|
public boolean getExecuteExistingDelayedTasksAfterShutdownPolicy() {
|
518 |
|
|
return executeExistingDelayedTasksAfterShutdown;
|
519 |
|
|
}
|
520 |
|
|
|
521 |
|
|
|
522 |
|
|
/**
|
523 |
|
|
* Initiates an orderly shutdown in which previously submitted
|
524 |
|
|
* tasks are executed, but no new tasks will be accepted. If the
|
525 |
|
|
* <tt>ExecuteExistingDelayedTasksAfterShutdownPolicy</tt> has
|
526 |
|
|
* been set <tt>false</tt>, existing delayed tasks whose delays
|
527 |
|
|
* have not yet elapsed are cancelled. And unless the
|
528 |
|
|
* <tt>ContinueExistingPeriodicTasksAfterShutdownPolicy</tt> has
|
529 |
|
|
* been set <tt>true</tt>, future executions of existing periodic
|
530 |
|
|
* tasks will be cancelled.
|
531 |
|
|
*/
|
532 |
|
|
public void shutdown() {
|
533 |
|
|
cancelUnwantedTasks();
|
534 |
|
|
super.shutdown();
|
535 |
|
|
}
|
536 |
|
|
|
537 |
|
|
/**
|
538 |
|
|
* Attempts to stop all actively executing tasks, halts the
|
539 |
|
|
* processing of waiting tasks, and returns a list of the tasks
|
540 |
|
|
* that were awaiting execution.
|
541 |
|
|
*
|
542 |
|
|
* <p>There are no guarantees beyond best-effort attempts to stop
|
543 |
|
|
* processing actively executing tasks. This implementation
|
544 |
|
|
* cancels tasks via {@link Thread#interrupt}, so any task that
|
545 |
|
|
* fails to respond to interrupts may never terminate.
|
546 |
|
|
*
|
547 |
|
|
* @return list of tasks that never commenced execution. Each
|
548 |
|
|
* element of this list is a {@link ScheduledFuture},
|
549 |
|
|
* including those tasks submitted using <tt>execute</tt>, which
|
550 |
|
|
* are for scheduling purposes used as the basis of a zero-delay
|
551 |
|
|
* <tt>ScheduledFuture</tt>.
|
552 |
|
|
* @throws SecurityException {@inheritDoc}
|
553 |
|
|
*/
|
554 |
|
|
public List<Runnable> shutdownNow() {
|
555 |
|
|
return super.shutdownNow();
|
556 |
|
|
}
|
557 |
|
|
|
558 |
|
|
/**
|
559 |
|
|
* Returns the task queue used by this executor. Each element of
|
560 |
|
|
* this queue is a {@link ScheduledFuture}, including those
|
561 |
|
|
* tasks submitted using <tt>execute</tt> which are for scheduling
|
562 |
|
|
* purposes used as the basis of a zero-delay
|
563 |
|
|
* <tt>ScheduledFuture</tt>. Iteration over this queue is
|
564 |
|
|
* <em>not</em> guaranteed to traverse tasks in the order in
|
565 |
|
|
* which they will execute.
|
566 |
|
|
*
|
567 |
|
|
* @return the task queue
|
568 |
|
|
*/
|
569 |
|
|
public BlockingQueue<Runnable> getQueue() {
|
570 |
|
|
return super.getQueue();
|
571 |
|
|
}
|
572 |
|
|
|
573 |
|
|
/**
|
574 |
|
|
* An annoying wrapper class to convince javac to use a
|
575 |
|
|
* DelayQueue<RunnableScheduledFuture> as a BlockingQueue<Runnable>
|
576 |
|
|
*/
|
577 |
|
|
private static class DelayedWorkQueue
|
578 |
|
|
extends AbstractCollection<Runnable>
|
579 |
|
|
implements BlockingQueue<Runnable> {
|
580 |
|
|
|
581 |
|
|
private final DelayQueue<RunnableScheduledFuture> dq = new DelayQueue<RunnableScheduledFuture>();
|
582 |
|
|
public Runnable poll() { return dq.poll(); }
|
583 |
|
|
public Runnable peek() { return dq.peek(); }
|
584 |
|
|
public Runnable take() throws InterruptedException { return dq.take(); }
|
585 |
|
|
public Runnable poll(long timeout, TimeUnit unit) throws InterruptedException {
|
586 |
|
|
return dq.poll(timeout, unit);
|
587 |
|
|
}
|
588 |
|
|
|
589 |
|
|
public boolean add(Runnable x) {
|
590 |
|
|
return dq.add((RunnableScheduledFuture)x);
|
591 |
|
|
}
|
592 |
|
|
public boolean offer(Runnable x) {
|
593 |
|
|
return dq.offer((RunnableScheduledFuture)x);
|
594 |
|
|
}
|
595 |
|
|
public void put(Runnable x) {
|
596 |
|
|
dq.put((RunnableScheduledFuture)x);
|
597 |
|
|
}
|
598 |
|
|
public boolean offer(Runnable x, long timeout, TimeUnit unit) {
|
599 |
|
|
return dq.offer((RunnableScheduledFuture)x, timeout, unit);
|
600 |
|
|
}
|
601 |
|
|
|
602 |
|
|
public Runnable remove() { return dq.remove(); }
|
603 |
|
|
public Runnable element() { return dq.element(); }
|
604 |
|
|
public void clear() { dq.clear(); }
|
605 |
|
|
public int drainTo(Collection<? super Runnable> c) { return dq.drainTo(c); }
|
606 |
|
|
public int drainTo(Collection<? super Runnable> c, int maxElements) {
|
607 |
|
|
return dq.drainTo(c, maxElements);
|
608 |
|
|
}
|
609 |
|
|
|
610 |
|
|
public int remainingCapacity() { return dq.remainingCapacity(); }
|
611 |
|
|
public boolean remove(Object x) { return dq.remove(x); }
|
612 |
|
|
public boolean contains(Object x) { return dq.contains(x); }
|
613 |
|
|
public int size() { return dq.size(); }
|
614 |
|
|
public boolean isEmpty() { return dq.isEmpty(); }
|
615 |
|
|
public Object[] toArray() { return dq.toArray(); }
|
616 |
|
|
public <T> T[] toArray(T[] array) { return dq.toArray(array); }
|
617 |
|
|
public Iterator<Runnable> iterator() {
|
618 |
|
|
return new Iterator<Runnable>() {
|
619 |
|
|
private Iterator<RunnableScheduledFuture> it = dq.iterator();
|
620 |
|
|
public boolean hasNext() { return it.hasNext(); }
|
621 |
|
|
public Runnable next() { return it.next(); }
|
622 |
|
|
public void remove() { it.remove(); }
|
623 |
|
|
};
|
624 |
|
|
}
|
625 |
|
|
}
|
626 |
|
|
}
|