100 |
|
* ForkJoinTasks (as may be determined using method {@link |
101 |
|
* #inForkJoinPool}). Attempts to invoke them in other contexts |
102 |
|
* result in exceptions or errors, possibly including |
103 |
< |
* ClassCastException. |
103 |
> |
* {@code ClassCastException}. |
104 |
|
* |
105 |
|
* <p>Most base support methods are {@code final}, to prevent |
106 |
|
* overriding of implementations that are intrinsically tied to the |
153 |
|
* single int to minimize footprint and to ensure atomicity (via |
154 |
|
* CAS). Status is initially zero, and takes on nonnegative |
155 |
|
* values until completed, upon which status holds value |
156 |
< |
* COMPLETED. CANCELLED, or EXCEPTIONAL. Tasks undergoing blocking |
156 |
> |
* NORMAL, CANCELLED, or EXCEPTIONAL. Tasks undergoing blocking |
157 |
|
* waits by other threads have the SIGNAL bit set. Completion of |
158 |
|
* a stolen task with SIGNAL set awakens any waiters via |
159 |
|
* notifyAll. Even though suboptimal for some purposes, we use |
205 |
|
} |
206 |
|
|
207 |
|
/** |
208 |
< |
* Record exception and set exceptional completion |
208 |
> |
* Records exception and sets exceptional completion. |
209 |
> |
* |
210 |
|
* @return status on exit |
211 |
|
*/ |
212 |
|
private void setExceptionalCompletion(Throwable rex) { |
215 |
|
} |
216 |
|
|
217 |
|
/** |
218 |
< |
* Blocks a worker thread until completion. Called only by pool. |
218 |
> |
* Blocks a worker thread until completion. Called only by |
219 |
> |
* pool. Currently unused -- pool-based waits use timeout |
220 |
> |
* version below. |
221 |
|
*/ |
222 |
|
final void internalAwaitDone() { |
223 |
|
int s; // the odd construction reduces lock bias effects |
224 |
|
while ((s = status) >= 0) { |
225 |
|
try { |
226 |
< |
synchronized(this) { |
226 |
> |
synchronized (this) { |
227 |
|
if (UNSAFE.compareAndSwapInt(this, statusOffset, s,SIGNAL)) |
228 |
|
wait(); |
229 |
|
} |
234 |
|
} |
235 |
|
|
236 |
|
/** |
237 |
+ |
* Blocks a worker thread until completed or timed out. Called |
238 |
+ |
* only by pool. |
239 |
+ |
* |
240 |
+ |
* @return status on exit |
241 |
+ |
*/ |
242 |
+ |
final int internalAwaitDone(long millis) { |
243 |
+ |
int s; |
244 |
+ |
if ((s = status) >= 0) { |
245 |
+ |
try { |
246 |
+ |
synchronized (this) { |
247 |
+ |
if (UNSAFE.compareAndSwapInt(this, statusOffset, s,SIGNAL)) |
248 |
+ |
wait(millis, 0); |
249 |
+ |
} |
250 |
+ |
} catch (InterruptedException ie) { |
251 |
+ |
cancelIfTerminating(); |
252 |
+ |
} |
253 |
+ |
s = status; |
254 |
+ |
} |
255 |
+ |
return s; |
256 |
+ |
} |
257 |
+ |
|
258 |
+ |
/** |
259 |
|
* Blocks a non-worker-thread until completion. |
260 |
|
*/ |
261 |
|
private void externalAwaitDone() { |
262 |
|
int s; |
263 |
|
while ((s = status) >= 0) { |
264 |
< |
synchronized(this) { |
264 |
> |
synchronized (this) { |
265 |
|
if (UNSAFE.compareAndSwapInt(this, statusOffset, s, SIGNAL)){ |
266 |
|
boolean interrupted = false; |
267 |
|
while (status >= 0) { |
339 |
|
|
340 |
|
/** |
341 |
|
* Commences performing this task, awaits its completion if |
342 |
< |
* necessary, and return its result, or throws an (unchecked) |
343 |
< |
* exception if the underlying computation did so. |
342 |
> |
* necessary, and returns its result, or throws an (unchecked) |
343 |
> |
* {@code RuntimeException} or {@code Error} if the underlying |
344 |
> |
* computation did so. |
345 |
|
* |
346 |
|
* @return the computed result |
347 |
|
*/ |
356 |
|
/** |
357 |
|
* Forks the given tasks, returning when {@code isDone} holds for |
358 |
|
* each task or an (unchecked) exception is encountered, in which |
359 |
< |
* case the exception is rethrown. If either task encounters an |
360 |
< |
* exception, the other one may be, but is not guaranteed to be, |
361 |
< |
* cancelled. If both tasks throw an exception, then this method |
362 |
< |
* throws one of them. The individual status of each task may be |
363 |
< |
* checked using {@link #getException()} and related methods. |
359 |
> |
* case the exception is rethrown. If more than one task |
360 |
> |
* encounters an exception, then this method throws any one of |
361 |
> |
* these exceptions. If any task encounters an exception, the |
362 |
> |
* other may be cancelled. However, the execution status of |
363 |
> |
* individual tasks is not guaranteed upon exceptional return. The |
364 |
> |
* status of each task may be obtained using {@link |
365 |
> |
* #getException()} and related methods to check if they have been |
366 |
> |
* cancelled, completed normally or exceptionally, or left |
367 |
> |
* unprocessed. |
368 |
|
* |
369 |
|
* <p>This method may be invoked only from within {@code |
370 |
|
* ForkJoinTask} computations (as may be determined using method |
385 |
|
/** |
386 |
|
* Forks the given tasks, returning when {@code isDone} holds for |
387 |
|
* each task or an (unchecked) exception is encountered, in which |
388 |
< |
* case the exception is rethrown. If any task encounters an |
389 |
< |
* exception, others may be, but are not guaranteed to be, |
390 |
< |
* cancelled. If more than one task encounters an exception, then |
391 |
< |
* this method throws any one of these exceptions. The individual |
392 |
< |
* status of each task may be checked using {@link #getException()} |
393 |
< |
* and related methods. |
388 |
> |
* case the exception is rethrown. If more than one task |
389 |
> |
* encounters an exception, then this method throws any one of |
390 |
> |
* these exceptions. If any task encounters an exception, others |
391 |
> |
* may be cancelled. However, the execution status of individual |
392 |
> |
* tasks is not guaranteed upon exceptional return. The status of |
393 |
> |
* each task may be obtained using {@link #getException()} and |
394 |
> |
* related methods to check if they have been cancelled, completed |
395 |
> |
* normally or exceptionally, or left unprocessed. |
396 |
|
* |
397 |
|
* <p>This method may be invoked only from within {@code |
398 |
|
* ForkJoinTask} computations (as may be determined using method |
439 |
|
/** |
440 |
|
* Forks all tasks in the specified collection, returning when |
441 |
|
* {@code isDone} holds for each task or an (unchecked) exception |
442 |
< |
* is encountered. If any task encounters an exception, others |
443 |
< |
* may be, but are not guaranteed to be, cancelled. If more than |
444 |
< |
* one task encounters an exception, then this method throws any |
445 |
< |
* one of these exceptions. The individual status of each task |
446 |
< |
* may be checked using {@link #getException()} and related |
447 |
< |
* methods. The behavior of this operation is undefined if the |
448 |
< |
* specified collection is modified while the operation is in |
449 |
< |
* progress. |
442 |
> |
* is encountered, in which case the exception is rethrown. If |
443 |
> |
* more than one task encounters an exception, then this method |
444 |
> |
* throws any one of these exceptions. If any task encounters an |
445 |
> |
* exception, others may be cancelled. However, the execution |
446 |
> |
* status of individual tasks is not guaranteed upon exceptional |
447 |
> |
* return. The status of each task may be obtained using {@link |
448 |
> |
* #getException()} and related methods to check if they have been |
449 |
> |
* cancelled, completed normally or exceptionally, or left |
450 |
> |
* unprocessed. |
451 |
|
* |
452 |
|
* <p>This method may be invoked only from within {@code |
453 |
|
* ForkJoinTask} computations (as may be determined using method |
543 |
|
} |
544 |
|
|
545 |
|
/** |
546 |
< |
* Cancels ignoring exceptions if worker is terminating |
546 |
> |
* Cancels if current thread is a terminating worker thread, |
547 |
> |
* ignoring any exceptions thrown by cancel. |
548 |
|
*/ |
549 |
|
final void cancelIfTerminating() { |
550 |
|
Thread t = Thread.currentThread(); |
621 |
|
|
622 |
|
/** |
623 |
|
* Completes this task, and if not already aborted or cancelled, |
624 |
< |
* returning a {@code null} result upon {@code join} and related |
625 |
< |
* operations. This method may be used to provide results for |
626 |
< |
* asynchronous tasks, or to provide alternative handling for |
627 |
< |
* tasks that would not otherwise complete normally. Its use in |
628 |
< |
* other situations is discouraged. This method is |
629 |
< |
* overridable, but overridden versions must invoke {@code super} |
630 |
< |
* implementation to maintain guarantees. |
624 |
> |
* returning the given value as the result of subsequent |
625 |
> |
* invocations of {@code join} and related operations. This method |
626 |
> |
* may be used to provide results for asynchronous tasks, or to |
627 |
> |
* provide alternative handling for tasks that would not otherwise |
628 |
> |
* complete normally. Its use in other situations is |
629 |
> |
* discouraged. This method is overridable, but overridden |
630 |
> |
* versions must invoke {@code super} implementation to maintain |
631 |
> |
* guarantees. |
632 |
|
* |
633 |
|
* @param value the result value for this task |
634 |
|
*/ |
678 |
|
*/ |
679 |
|
boolean interrupted = false; |
680 |
|
boolean dec = false; // true if pool count decremented |
681 |
+ |
long nanos = unit.toNanos(timeout); |
682 |
|
for (;;) { |
683 |
< |
if (Thread.interrupted() && pool == null) { |
683 |
> |
if (pool == null && Thread.interrupted()) { |
684 |
|
interrupted = true; |
685 |
|
break; |
686 |
|
} |
689 |
|
break; |
690 |
|
if (UNSAFE.compareAndSwapInt(this, statusOffset, s, SIGNAL)) { |
691 |
|
long startTime = System.nanoTime(); |
656 |
– |
long nanos = unit.toNanos(timeout); |
692 |
|
long nt; // wait time |
693 |
|
while (status >= 0 && |
694 |
|
(nt = nanos - (System.nanoTime() - startTime)) > 0) { |
698 |
|
long ms = nt / 1000000; |
699 |
|
int ns = (int) (nt % 1000000); |
700 |
|
try { |
701 |
< |
synchronized(this) { |
701 |
> |
synchronized (this) { |
702 |
|
if (status >= 0) |
703 |
|
wait(ms, ns); |
704 |
|
} |
765 |
|
/** |
766 |
|
* Commences performing this task and awaits its completion if |
767 |
|
* necessary, without returning its result or throwing its |
768 |
< |
* exception. This method may be useful when processing |
734 |
< |
* collections of tasks when some have been cancelled or otherwise |
735 |
< |
* known to have aborted. |
768 |
> |
* exception. |
769 |
|
*/ |
770 |
|
public final void quietlyInvoke() { |
771 |
|
if (status >= 0) { |
1102 |
|
private static final long serialVersionUID = -7721805057305804111L; |
1103 |
|
|
1104 |
|
/** |
1105 |
< |
* Saves the state to a stream. |
1105 |
> |
* Saves the state to a stream (that is, serializes it). |
1106 |
|
* |
1107 |
|
* @serialData the current run status and the exception thrown |
1108 |
|
* during execution, or {@code null} if none |
1115 |
|
} |
1116 |
|
|
1117 |
|
/** |
1118 |
< |
* Reconstitutes the instance from a stream. |
1118 |
> |
* Reconstitutes the instance from a stream (that is, deserializes it). |
1119 |
|
* |
1120 |
|
* @param s the stream |
1121 |
|
*/ |