| 28 |
|
* <tt>corePoolSize</tt> threads and an unbounded queue, adjustments |
| 29 |
|
* to <tt>maximumPoolSize</tt> have no useful effect. |
| 30 |
|
* |
| 31 |
+ |
* <p>This class supports protected extension method |
| 32 |
+ |
* <tt>decorateTask</tt> (one version each for <tt>Runnable</tt> and |
| 33 |
+ |
* <tt>Callable</tt>) that can be used to customize the concrete task |
| 34 |
+ |
* types used to execute commands. By default, |
| 35 |
+ |
* a <tt>ScheduledThreadPoolExecutor</tt> uses |
| 36 |
+ |
* a task type extending {@link FutureTask}. However, this may |
| 37 |
+ |
* be modified or replaced using subclasses of the form: |
| 38 |
+ |
* <pre> |
| 39 |
+ |
* public class CustomScheduledExecutor extends ScheduledThreadPoolExecutor { |
| 40 |
+ |
* |
| 41 |
+ |
* static class CustomTask<V> implements RunnableScheduledFuture<V> { ... } |
| 42 |
+ |
* |
| 43 |
+ |
* <V> protected RunnableScheduledFuture<V> decorateTask( |
| 44 |
+ |
* Runnable r, RunnableScheduledFuture<V> task) { |
| 45 |
+ |
* return new CustomTask<V>(r, task); |
| 46 |
+ |
* } |
| 47 |
+ |
* |
| 48 |
+ |
* <V> protected RunnableScheduledFuture<V> decorateTask( |
| 49 |
+ |
* Callable c, RunnableScheduledFuture<V> task) { |
| 50 |
+ |
* return new CustomTask<V>(c, task); |
| 51 |
+ |
* } |
| 52 |
+ |
* // ... add constructors, etc. |
| 53 |
+ |
* } |
| 54 |
+ |
* </pre> |
| 55 |
|
* @since 1.5 |
| 56 |
|
* @author Doug Lea |
| 57 |
|
*/ |
| 154 |
|
* Returns true if this is a periodic (not a one-shot) action. |
| 155 |
|
* @return true if periodic |
| 156 |
|
*/ |
| 157 |
< |
boolean isPeriodic() { |
| 157 |
> |
public boolean isPeriodic() { |
| 158 |
|
return period != 0; |
| 159 |
|
} |
| 160 |
|
|
| 222 |
|
Object[] entries = super.getQueue().toArray(); |
| 223 |
|
for (int i = 0; i < entries.length; ++i) { |
| 224 |
|
Object e = entries[i]; |
| 225 |
< |
if (e instanceof ScheduledFutureTask) { |
| 226 |
< |
ScheduledFutureTask<?> t = (ScheduledFutureTask<?>)e; |
| 225 |
> |
if (e instanceof RunnableScheduledFuture) { |
| 226 |
> |
RunnableScheduledFuture<?> t = (RunnableScheduledFuture<?>)e; |
| 227 |
|
if (t.isPeriodic()? !keepPeriodic : !keepDelayed) |
| 228 |
|
t.cancel(false); |
| 229 |
|
} |
| 234 |
|
} |
| 235 |
|
|
| 236 |
|
public boolean remove(Runnable task) { |
| 237 |
< |
if (!(task instanceof ScheduledFutureTask)) |
| 237 |
> |
if (!(task instanceof RunnableScheduledFuture)) |
| 238 |
|
return false; |
| 239 |
|
return getQueue().remove(task); |
| 240 |
|
} |
| 241 |
|
|
| 242 |
< |
|
| 242 |
> |
/** |
| 243 |
> |
* Modify or replace the task used to execute a runnable. |
| 244 |
> |
* This method can be used to override the concrete |
| 245 |
> |
* class used for managing internal tasks. |
| 246 |
> |
* The default implementation simply returns the given |
| 247 |
> |
* task. |
| 248 |
> |
* |
| 249 |
> |
* @param runnable the submitted Runnable |
| 250 |
> |
* @param task the task created to execute the runnable |
| 251 |
> |
* @return a task that can execute the runnable |
| 252 |
> |
* @since 1.6 |
| 253 |
> |
*/ |
| 254 |
|
protected <V> RunnableScheduledFuture<V> decorateTask( |
| 255 |
< |
Runnable runnable, RunnableScheduledFuture<V> f) { |
| 256 |
< |
return f; |
| 255 |
> |
Runnable runnable, RunnableScheduledFuture<V> task) { |
| 256 |
> |
return task; |
| 257 |
|
} |
| 258 |
|
|
| 259 |
+ |
/** |
| 260 |
+ |
* Modify or replace the task used to execute a callable. |
| 261 |
+ |
* This method can be used to override the concrete |
| 262 |
+ |
* class used for managing internal tasks. |
| 263 |
+ |
* The default implementation simply returns the given |
| 264 |
+ |
* task. |
| 265 |
+ |
* |
| 266 |
+ |
* @param callable the submitted Callable |
| 267 |
+ |
* @param task the task created to execute the callable |
| 268 |
+ |
* @return a task that can execute the callable |
| 269 |
+ |
* @since 1.6 |
| 270 |
+ |
*/ |
| 271 |
|
protected <V> RunnableScheduledFuture<V> decorateTask( |
| 272 |
< |
Callable<V> callable, RunnableScheduledFuture<V> f) { |
| 273 |
< |
return f; |
| 272 |
> |
Callable<V> callable, RunnableScheduledFuture<V> task) { |
| 273 |
> |
return task; |
| 274 |
|
} |
| 275 |
|
|
| 276 |
|
/** |
| 549 |
|
|
| 550 |
|
/** |
| 551 |
|
* An annoying wrapper class to convince generics compiler to |
| 552 |
< |
* use a DelayQueue<ScheduledFutureTask> as a BlockingQueue<Runnable> |
| 552 |
> |
* use a DelayQueue<RunnableScheduledFuture> as a BlockingQueue<Runnable> |
| 553 |
|
*/ |
| 554 |
|
private static class DelayedWorkQueue |
| 555 |
|
extends AbstractCollection<Runnable> |
| 556 |
|
implements BlockingQueue<Runnable> { |
| 557 |
|
|
| 558 |
< |
private final DelayQueue<ScheduledFutureTask> dq = new DelayQueue<ScheduledFutureTask>(); |
| 558 |
> |
private final DelayQueue<RunnableScheduledFuture> dq = new DelayQueue<RunnableScheduledFuture>(); |
| 559 |
|
public Runnable poll() { return dq.poll(); } |
| 560 |
|
public Runnable peek() { return dq.peek(); } |
| 561 |
|
public Runnable take() throws InterruptedException { return dq.take(); } |
| 563 |
|
return dq.poll(timeout, unit); |
| 564 |
|
} |
| 565 |
|
|
| 566 |
< |
public boolean add(Runnable x) { return dq.add((ScheduledFutureTask)x); } |
| 567 |
< |
public boolean offer(Runnable x) { return dq.offer((ScheduledFutureTask)x); } |
| 566 |
> |
public boolean add(Runnable x) { return dq.add((RunnableScheduledFuture)x); } |
| 567 |
> |
public boolean offer(Runnable x) { return dq.offer((RunnableScheduledFuture)x); } |
| 568 |
|
public void put(Runnable x) { |
| 569 |
< |
dq.put((ScheduledFutureTask)x); |
| 569 |
> |
dq.put((RunnableScheduledFuture)x); |
| 570 |
|
} |
| 571 |
|
public boolean offer(Runnable x, long timeout, TimeUnit unit) { |
| 572 |
< |
return dq.offer((ScheduledFutureTask)x, timeout, unit); |
| 572 |
> |
return dq.offer((RunnableScheduledFuture)x, timeout, unit); |
| 573 |
|
} |
| 574 |
|
|
| 575 |
|
public Runnable remove() { return dq.remove(); } |
| 589 |
|
public <T> T[] toArray(T[] array) { return dq.toArray(array); } |
| 590 |
|
public Iterator<Runnable> iterator() { |
| 591 |
|
return new Iterator<Runnable>() { |
| 592 |
< |
private Iterator<ScheduledFutureTask> it = dq.iterator(); |
| 592 |
> |
private Iterator<RunnableScheduledFuture> it = dq.iterator(); |
| 593 |
|
public boolean hasNext() { return it.hasNext(); } |
| 594 |
|
public Runnable next() { return it.next(); } |
| 595 |
|
public void remove() { it.remove(); } |
