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package jsr166y; |
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import java.util.concurrent.*; |
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import java.io.Serializable; |
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import java.util.Collection; |
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import java.util.Collections; |
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import java.util.RandomAccess; |
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import java.util.Map; |
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import java.util.WeakHashMap; |
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import java.util.concurrent.Callable; |
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import java.util.concurrent.CancellationException; |
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import java.util.concurrent.ExecutionException; |
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import java.util.concurrent.Executor; |
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import java.util.concurrent.ExecutorService; |
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import java.util.concurrent.Future; |
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import java.util.concurrent.RejectedExecutionException; |
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import java.util.concurrent.RunnableFuture; |
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import java.util.concurrent.TimeUnit; |
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import java.util.concurrent.TimeoutException; |
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/** |
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* Abstract base class for tasks that run within a {@link ForkJoinPool}. |
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* start other subtasks. As indicated by the name of this class, |
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* many programs using {@code ForkJoinTask} employ only methods |
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* {@link #fork} and {@link #join}, or derivatives such as {@link |
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* #invokeAll}. However, this class also provides a number of other |
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* methods that can come into play in advanced usages, as well as |
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* extension mechanics that allow support of new forms of fork/join |
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* processing. |
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* #invokeAll(ForkJoinTask...) invokeAll}. However, this class also |
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* provides a number of other methods that can come into play in |
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* advanced usages, as well as extension mechanics that allow |
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* support of new forms of fork/join processing. |
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* |
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* <p>A {@code ForkJoinTask} is a lightweight form of {@link Future}. |
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* The efficiency of {@code ForkJoinTask}s stems from a set of |
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* ForkJoinTasks (as may be determined using method {@link |
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* #inForkJoinPool}). Attempts to invoke them in other contexts |
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* result in exceptions or errors, possibly including |
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* ClassCastException. |
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* {@code ClassCastException}. |
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* |
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* <p>Method {@link #join} and its variants are appropriate for use |
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* only when completion dependencies are acyclic; that is, the |
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* parallel computation can be described as a directed acyclic graph |
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* (DAG). Otherwise, executions may encounter a form of deadlock as |
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* tasks cyclically wait for each other. However, this framework |
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* supports other methods and techniques (for example the use of |
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* {@link Phaser}, {@link #helpQuiesce}, and {@link #complete}) that |
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* may be of use in constructing custom subclasses for problems that |
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* are not statically structured as DAGs. |
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* |
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* <p>Most base support methods are {@code final}, to prevent |
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* overriding of implementations that are intrinsically tied to the |
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* computation. Large tasks should be split into smaller subtasks, |
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* usually via recursive decomposition. As a very rough rule of thumb, |
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* a task should perform more than 100 and less than 10000 basic |
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* computational steps. If tasks are too big, then parallelism cannot |
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* improve throughput. If too small, then memory and internal task |
139 |
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* maintenance overhead may overwhelm processing. |
137 |
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* computational steps, and should avoid indefinite looping. If tasks |
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* are too big, then parallelism cannot improve throughput. If too |
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* small, then memory and internal task maintenance overhead may |
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* overwhelm processing. |
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* |
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* <p>This class provides {@code adapt} methods for {@link Runnable} |
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* and {@link Callable}, that may be of use when mixing execution of |
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* single int to minimize footprint and to ensure atomicity (via |
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* CAS). Status is initially zero, and takes on nonnegative |
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* values until completed, upon which status holds value |
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* COMPLETED. CANCELLED, or EXCEPTIONAL. Tasks undergoing blocking |
175 |
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* NORMAL, CANCELLED, or EXCEPTIONAL. Tasks undergoing blocking |
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* waits by other threads have the SIGNAL bit set. Completion of |
177 |
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* a stolen task with SIGNAL set awakens any waiters via |
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* notifyAll. Even though suboptimal for some purposes, we use |
224 |
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} |
225 |
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|
226 |
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/** |
227 |
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* Record exception and set exceptional completion |
227 |
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* Records exception and sets exceptional completion. |
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* |
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* @return status on exit |
230 |
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*/ |
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private void setExceptionalCompletion(Throwable rex) { |
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} |
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/** |
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* Blocks a worker thread until completion. Called only by pool. |
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* Blocks a worker thread until completed or timed out. Called |
238 |
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* only by pool. |
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*/ |
240 |
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final void internalAwaitDone() { |
241 |
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int s; // the odd construction reduces lock bias effects |
242 |
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while ((s = status) >= 0) { |
243 |
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try { |
244 |
< |
synchronized(this) { |
245 |
< |
if (UNSAFE.compareAndSwapInt(this, statusOffset, s,SIGNAL)) |
246 |
< |
wait(); |
240 |
> |
final void internalAwaitDone(long millis, int nanos) { |
241 |
> |
int s = status; |
242 |
> |
if ((s == 0 && |
243 |
> |
UNSAFE.compareAndSwapInt(this, statusOffset, 0, SIGNAL)) || |
244 |
> |
s > 0) { |
245 |
> |
try { // the odd construction reduces lock bias effects |
246 |
> |
synchronized (this) { |
247 |
> |
if (status > 0) |
248 |
> |
wait(millis, nanos); |
249 |
> |
else |
250 |
> |
notifyAll(); |
251 |
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} |
252 |
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} catch (InterruptedException ie) { |
253 |
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cancelIfTerminating(); |
259 |
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* Blocks a non-worker-thread until completion. |
260 |
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*/ |
261 |
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private void externalAwaitDone() { |
262 |
< |
int s; |
263 |
< |
while ((s = status) >= 0) { |
264 |
< |
synchronized(this) { |
265 |
< |
if (UNSAFE.compareAndSwapInt(this, statusOffset, s, SIGNAL)){ |
266 |
< |
boolean interrupted = false; |
267 |
< |
while (status >= 0) { |
262 |
> |
if (status >= 0) { |
263 |
> |
boolean interrupted = false; |
264 |
> |
synchronized (this) { |
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for (;;) { |
266 |
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int s = status; |
267 |
> |
if (s == 0) |
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> |
UNSAFE.compareAndSwapInt(this, statusOffset, |
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> |
0, SIGNAL); |
270 |
> |
else if (s < 0) { |
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notifyAll(); |
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> |
break; |
273 |
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} |
274 |
> |
else { |
275 |
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try { |
276 |
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wait(); |
277 |
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} catch (InterruptedException ie) { |
278 |
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interrupted = true; |
279 |
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} |
280 |
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} |
281 |
< |
if (interrupted) |
282 |
< |
Thread.currentThread().interrupt(); |
283 |
< |
break; |
281 |
> |
} |
282 |
> |
} |
283 |
> |
if (interrupted) |
284 |
> |
Thread.currentThread().interrupt(); |
285 |
> |
} |
286 |
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} |
287 |
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|
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> |
/** |
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* Blocks a non-worker-thread until completion or interruption or timeout. |
290 |
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*/ |
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> |
private void externalInterruptibleAwaitDone(boolean timed, long nanos) |
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throws InterruptedException { |
293 |
> |
if (Thread.interrupted()) |
294 |
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throw new InterruptedException(); |
295 |
> |
if (status >= 0) { |
296 |
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long startTime = timed ? System.nanoTime() : 0L; |
297 |
> |
synchronized (this) { |
298 |
> |
for (;;) { |
299 |
> |
long nt; |
300 |
> |
int s = status; |
301 |
> |
if (s == 0) |
302 |
> |
UNSAFE.compareAndSwapInt(this, statusOffset, |
303 |
> |
0, SIGNAL); |
304 |
> |
else if (s < 0) { |
305 |
> |
notifyAll(); |
306 |
> |
break; |
307 |
> |
} |
308 |
> |
else if (!timed) |
309 |
> |
wait(); |
310 |
> |
else if ((nt = nanos - (System.nanoTime()-startTime)) > 0L) |
311 |
> |
wait(nt / 1000000, (int)(nt % 1000000)); |
312 |
> |
else |
313 |
> |
break; |
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} |
315 |
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} |
316 |
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} |
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* #isDone} returning {@code true}. |
346 |
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* |
347 |
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* <p>This method may be invoked only from within {@code |
348 |
< |
* ForkJoinTask} computations (as may be determined using method |
348 |
> |
* ForkJoinPool} computations (as may be determined using method |
349 |
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* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
350 |
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* result in exceptions or errors, possibly including {@code |
351 |
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* ClassCastException}. |
359 |
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} |
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|
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/** |
362 |
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* Returns the result of the computation when it {@link #isDone is done}. |
363 |
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* This method differs from {@link #get()} in that |
362 |
> |
* Returns the result of the computation when it {@link #isDone is |
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> |
* done}. This method differs from {@link #get()} in that |
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* abnormal completion results in {@code RuntimeException} or |
365 |
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* {@code Error}, not {@code ExecutionException}. |
365 |
> |
* {@code Error}, not {@code ExecutionException}, and that |
366 |
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* interrupts of the calling thread do <em>not</em> cause the |
367 |
> |
* method to abruptly return by throwing {@code |
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> |
* InterruptedException}. |
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* |
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* @return the computed result |
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*/ |
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|
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/** |
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* Commences performing this task, awaits its completion if |
382 |
< |
* necessary, and return its result, or throws an (unchecked) |
383 |
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* exception if the underlying computation did so. |
382 |
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* necessary, and returns its result, or throws an (unchecked) |
383 |
> |
* {@code RuntimeException} or {@code Error} if the underlying |
384 |
> |
* computation did so. |
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* |
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* @return the computed result |
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*/ |
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/** |
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* Forks the given tasks, returning when {@code isDone} holds for |
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* each task or an (unchecked) exception is encountered, in which |
399 |
< |
* case the exception is rethrown. If either task encounters an |
400 |
< |
* exception, the other one may be, but is not guaranteed to be, |
401 |
< |
* cancelled. If both tasks throw an exception, then this method |
402 |
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* throws one of them. The individual status of each task may be |
403 |
< |
* checked using {@link #getException()} and related methods. |
399 |
> |
* case the exception is rethrown. If more than one task |
400 |
> |
* encounters an exception, then this method throws any one of |
401 |
> |
* these exceptions. If any task encounters an exception, the |
402 |
> |
* other may be cancelled. However, the execution status of |
403 |
> |
* individual tasks is not guaranteed upon exceptional return. The |
404 |
> |
* status of each task may be obtained using {@link |
405 |
> |
* #getException()} and related methods to check if they have been |
406 |
> |
* cancelled, completed normally or exceptionally, or left |
407 |
> |
* unprocessed. |
408 |
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* |
409 |
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* <p>This method may be invoked only from within {@code |
410 |
< |
* ForkJoinTask} computations (as may be determined using method |
410 |
> |
* ForkJoinPool} computations (as may be determined using method |
411 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
412 |
|
* result in exceptions or errors, possibly including {@code |
413 |
|
* ClassCastException}. |
425 |
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/** |
426 |
|
* Forks the given tasks, returning when {@code isDone} holds for |
427 |
|
* each task or an (unchecked) exception is encountered, in which |
428 |
< |
* case the exception is rethrown. If any task encounters an |
429 |
< |
* exception, others may be, but are not guaranteed to be, |
430 |
< |
* cancelled. If more than one task encounters an exception, then |
431 |
< |
* this method throws any one of these exceptions. The individual |
432 |
< |
* status of each task may be checked using {@link #getException()} |
433 |
< |
* and related methods. |
428 |
> |
* case the exception is rethrown. If more than one task |
429 |
> |
* encounters an exception, then this method throws any one of |
430 |
> |
* these exceptions. If any task encounters an exception, others |
431 |
> |
* may be cancelled. However, the execution status of individual |
432 |
> |
* tasks is not guaranteed upon exceptional return. The status of |
433 |
> |
* each task may be obtained using {@link #getException()} and |
434 |
> |
* related methods to check if they have been cancelled, completed |
435 |
> |
* normally or exceptionally, or left unprocessed. |
436 |
|
* |
437 |
|
* <p>This method may be invoked only from within {@code |
438 |
< |
* ForkJoinTask} computations (as may be determined using method |
438 |
> |
* ForkJoinPool} computations (as may be determined using method |
439 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
440 |
|
* result in exceptions or errors, possibly including {@code |
441 |
|
* ClassCastException}. |
479 |
|
/** |
480 |
|
* Forks all tasks in the specified collection, returning when |
481 |
|
* {@code isDone} holds for each task or an (unchecked) exception |
482 |
< |
* is encountered. If any task encounters an exception, others |
483 |
< |
* may be, but are not guaranteed to be, cancelled. If more than |
484 |
< |
* one task encounters an exception, then this method throws any |
485 |
< |
* one of these exceptions. The individual status of each task |
486 |
< |
* may be checked using {@link #getException()} and related |
487 |
< |
* methods. The behavior of this operation is undefined if the |
488 |
< |
* specified collection is modified while the operation is in |
489 |
< |
* progress. |
482 |
> |
* is encountered, in which case the exception is rethrown. If |
483 |
> |
* more than one task encounters an exception, then this method |
484 |
> |
* throws any one of these exceptions. If any task encounters an |
485 |
> |
* exception, others may be cancelled. However, the execution |
486 |
> |
* status of individual tasks is not guaranteed upon exceptional |
487 |
> |
* return. The status of each task may be obtained using {@link |
488 |
> |
* #getException()} and related methods to check if they have been |
489 |
> |
* cancelled, completed normally or exceptionally, or left |
490 |
> |
* unprocessed. |
491 |
|
* |
492 |
|
* <p>This method may be invoked only from within {@code |
493 |
< |
* ForkJoinTask} computations (as may be determined using method |
493 |
> |
* ForkJoinPool} computations (as may be determined using method |
494 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
495 |
|
* result in exceptions or errors, possibly including {@code |
496 |
|
* ClassCastException}. |
542 |
|
|
543 |
|
/** |
544 |
|
* Attempts to cancel execution of this task. This attempt will |
545 |
< |
* fail if the task has already completed, has already been |
546 |
< |
* cancelled, or could not be cancelled for some other reason. If |
547 |
< |
* successful, and this task has not started when cancel is |
548 |
< |
* called, execution of this task is suppressed, {@link |
549 |
< |
* #isCancelled} will report true, and {@link #join} will result |
550 |
< |
* in a {@code CancellationException} being thrown. |
545 |
> |
* fail if the task has already completed or could not be |
546 |
> |
* cancelled for some other reason. If successful, and this task |
547 |
> |
* has not started when {@code cancel} is called, execution of |
548 |
> |
* this task is suppressed. After this method returns |
549 |
> |
* successfully, unless there is an intervening call to {@link |
550 |
> |
* #reinitialize}, subsequent calls to {@link #isCancelled}, |
551 |
> |
* {@link #isDone}, and {@code cancel} will return {@code true} |
552 |
> |
* and calls to {@link #join} and related methods will result in |
553 |
> |
* {@code CancellationException}. |
554 |
|
* |
555 |
|
* <p>This method may be overridden in subclasses, but if so, must |
556 |
< |
* still ensure that these minimal properties hold. In particular, |
557 |
< |
* the {@code cancel} method itself must not throw exceptions. |
556 |
> |
* still ensure that these properties hold. In particular, the |
557 |
> |
* {@code cancel} method itself must not throw exceptions. |
558 |
|
* |
559 |
|
* <p>This method is designed to be invoked by <em>other</em> |
560 |
|
* tasks. To terminate the current task, you can just return or |
561 |
|
* throw an unchecked exception from its computation method, or |
562 |
|
* invoke {@link #completeExceptionally}. |
563 |
|
* |
564 |
< |
* @param mayInterruptIfRunning this value is ignored in the |
565 |
< |
* default implementation because tasks are not |
566 |
< |
* cancelled via interruption |
564 |
> |
* @param mayInterruptIfRunning this value has no effect in the |
565 |
> |
* default implementation because interrupts are not used to |
566 |
> |
* control cancellation. |
567 |
|
* |
568 |
|
* @return {@code true} if this task is now cancelled |
569 |
|
*/ |
586 |
|
} |
587 |
|
|
588 |
|
/** |
589 |
< |
* Cancels ignoring exceptions if worker is terminating |
589 |
> |
* Cancels if current thread is a terminating worker thread, |
590 |
> |
* ignoring any exceptions thrown by cancel. |
591 |
|
*/ |
592 |
|
final void cancelIfTerminating() { |
593 |
|
Thread t = Thread.currentThread(); |
664 |
|
|
665 |
|
/** |
666 |
|
* Completes this task, and if not already aborted or cancelled, |
667 |
< |
* returning a {@code null} result upon {@code join} and related |
668 |
< |
* operations. This method may be used to provide results for |
669 |
< |
* asynchronous tasks, or to provide alternative handling for |
670 |
< |
* tasks that would not otherwise complete normally. Its use in |
671 |
< |
* other situations is discouraged. This method is |
672 |
< |
* overridable, but overridden versions must invoke {@code super} |
673 |
< |
* implementation to maintain guarantees. |
667 |
> |
* returning the given value as the result of subsequent |
668 |
> |
* invocations of {@code join} and related operations. This method |
669 |
> |
* may be used to provide results for asynchronous tasks, or to |
670 |
> |
* provide alternative handling for tasks that would not otherwise |
671 |
> |
* complete normally. Its use in other situations is |
672 |
> |
* discouraged. This method is overridable, but overridden |
673 |
> |
* versions must invoke {@code super} implementation to maintain |
674 |
> |
* guarantees. |
675 |
|
* |
676 |
|
* @param value the result value for this task |
677 |
|
*/ |
685 |
|
setCompletion(NORMAL); |
686 |
|
} |
687 |
|
|
688 |
+ |
/** |
689 |
+ |
* Waits if necessary for the computation to complete, and then |
690 |
+ |
* retrieves its result. |
691 |
+ |
* |
692 |
+ |
* @return the computed result |
693 |
+ |
* @throws CancellationException if the computation was cancelled |
694 |
+ |
* @throws ExecutionException if the computation threw an |
695 |
+ |
* exception |
696 |
+ |
* @throws InterruptedException if the current thread is not a |
697 |
+ |
* member of a ForkJoinPool and was interrupted while waiting |
698 |
+ |
*/ |
699 |
|
public final V get() throws InterruptedException, ExecutionException { |
700 |
< |
quietlyJoin(); |
701 |
< |
if (Thread.interrupted()) |
702 |
< |
throw new InterruptedException(); |
700 |
> |
Thread t = Thread.currentThread(); |
701 |
> |
if (t instanceof ForkJoinWorkerThread) |
702 |
> |
quietlyJoin(); |
703 |
> |
else |
704 |
> |
externalInterruptibleAwaitDone(false, 0L); |
705 |
|
int s = status; |
706 |
< |
if (s < NORMAL) { |
706 |
> |
if (s != NORMAL) { |
707 |
|
Throwable ex; |
708 |
|
if (s == CANCELLED) |
709 |
|
throw new CancellationException(); |
713 |
|
return getRawResult(); |
714 |
|
} |
715 |
|
|
716 |
+ |
/** |
717 |
+ |
* Waits if necessary for at most the given time for the computation |
718 |
+ |
* to complete, and then retrieves its result, if available. |
719 |
+ |
* |
720 |
+ |
* @param timeout the maximum time to wait |
721 |
+ |
* @param unit the time unit of the timeout argument |
722 |
+ |
* @return the computed result |
723 |
+ |
* @throws CancellationException if the computation was cancelled |
724 |
+ |
* @throws ExecutionException if the computation threw an |
725 |
+ |
* exception |
726 |
+ |
* @throws InterruptedException if the current thread is not a |
727 |
+ |
* member of a ForkJoinPool and was interrupted while waiting |
728 |
+ |
* @throws TimeoutException if the wait timed out |
729 |
+ |
*/ |
730 |
|
public final V get(long timeout, TimeUnit unit) |
731 |
|
throws InterruptedException, ExecutionException, TimeoutException { |
732 |
+ |
long nanos = unit.toNanos(timeout); |
733 |
|
Thread t = Thread.currentThread(); |
734 |
< |
ForkJoinPool pool; |
735 |
< |
if (t instanceof ForkJoinWorkerThread) { |
630 |
< |
ForkJoinWorkerThread w = (ForkJoinWorkerThread) t; |
631 |
< |
if (status >= 0 && w.unpushTask(this)) |
632 |
< |
quietlyExec(); |
633 |
< |
pool = w.pool; |
634 |
< |
} |
734 |
> |
if (t instanceof ForkJoinWorkerThread) |
735 |
> |
((ForkJoinWorkerThread)t).joinTask(this, true, nanos); |
736 |
|
else |
737 |
< |
pool = null; |
738 |
< |
/* |
739 |
< |
* Timed wait loop intermixes cases for FJ (pool != null) and |
639 |
< |
* non FJ threads. For FJ, decrement pool count but don't try |
640 |
< |
* for replacement; increment count on completion. For non-FJ, |
641 |
< |
* deal with interrupts. This is messy, but a little less so |
642 |
< |
* than is splitting the FJ and nonFJ cases. |
643 |
< |
*/ |
644 |
< |
boolean interrupted = false; |
645 |
< |
boolean dec = false; // true if pool count decremented |
646 |
< |
for (;;) { |
647 |
< |
if (Thread.interrupted() && pool == null) { |
648 |
< |
interrupted = true; |
649 |
< |
break; |
650 |
< |
} |
651 |
< |
int s = status; |
652 |
< |
if (s < 0) |
653 |
< |
break; |
654 |
< |
if (UNSAFE.compareAndSwapInt(this, statusOffset, s, SIGNAL)) { |
655 |
< |
long startTime = System.nanoTime(); |
656 |
< |
long nanos = unit.toNanos(timeout); |
657 |
< |
long nt; // wait time |
658 |
< |
while (status >= 0 && |
659 |
< |
(nt = nanos - (System.nanoTime() - startTime)) > 0) { |
660 |
< |
if (pool != null && !dec) |
661 |
< |
dec = pool.tryDecrementRunningCount(); |
662 |
< |
else { |
663 |
< |
long ms = nt / 1000000; |
664 |
< |
int ns = (int) (nt % 1000000); |
665 |
< |
try { |
666 |
< |
synchronized(this) { |
667 |
< |
if (status >= 0) |
668 |
< |
wait(ms, ns); |
669 |
< |
} |
670 |
< |
} catch (InterruptedException ie) { |
671 |
< |
if (pool != null) |
672 |
< |
cancelIfTerminating(); |
673 |
< |
else { |
674 |
< |
interrupted = true; |
675 |
< |
break; |
676 |
< |
} |
677 |
< |
} |
678 |
< |
} |
679 |
< |
} |
680 |
< |
break; |
681 |
< |
} |
682 |
< |
} |
683 |
< |
if (pool != null && dec) |
684 |
< |
pool.incrementRunningCount(); |
685 |
< |
if (interrupted) |
686 |
< |
throw new InterruptedException(); |
687 |
< |
int es = status; |
688 |
< |
if (es != NORMAL) { |
737 |
> |
externalInterruptibleAwaitDone(true, nanos); |
738 |
> |
int s = status; |
739 |
> |
if (s != NORMAL) { |
740 |
|
Throwable ex; |
741 |
< |
if (es == CANCELLED) |
741 |
> |
if (s == CANCELLED) |
742 |
|
throw new CancellationException(); |
743 |
< |
if (es == EXCEPTIONAL && (ex = exceptionMap.get(this)) != null) |
743 |
> |
if (s == EXCEPTIONAL && (ex = exceptionMap.get(this)) != null) |
744 |
|
throw new ExecutionException(ex); |
745 |
|
throw new TimeoutException(); |
746 |
|
} |
771 |
|
return; |
772 |
|
} |
773 |
|
} |
774 |
< |
w.joinTask(this); |
774 |
> |
w.joinTask(this, false, 0L); |
775 |
|
} |
776 |
|
} |
777 |
|
else |
781 |
|
/** |
782 |
|
* Commences performing this task and awaits its completion if |
783 |
|
* necessary, without returning its result or throwing its |
784 |
< |
* exception. This method may be useful when processing |
734 |
< |
* collections of tasks when some have been cancelled or otherwise |
735 |
< |
* known to have aborted. |
784 |
> |
* exception. |
785 |
|
*/ |
786 |
|
public final void quietlyInvoke() { |
787 |
|
if (status >= 0) { |
807 |
|
* processed. |
808 |
|
* |
809 |
|
* <p>This method may be invoked only from within {@code |
810 |
< |
* ForkJoinTask} computations (as may be determined using method |
810 |
> |
* ForkJoinPool} computations (as may be determined using method |
811 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
812 |
|
* result in exceptions or errors, possibly including {@code |
813 |
|
* ClassCastException}. |
826 |
|
* under any other usage conditions are not guaranteed. |
827 |
|
* This method may be useful when executing |
828 |
|
* pre-constructed trees of subtasks in loops. |
829 |
+ |
* |
830 |
+ |
* <p>Upon completion of this method, {@code isDone()} reports |
831 |
+ |
* {@code false}, and {@code getException()} reports {@code |
832 |
+ |
* null}. However, the value returned by {@code getRawResult} is |
833 |
+ |
* unaffected. To clear this value, you can invoke {@code |
834 |
+ |
* setRawResult(null)}. |
835 |
|
*/ |
836 |
|
public void reinitialize() { |
837 |
|
if (status == EXCEPTIONAL) |
853 |
|
} |
854 |
|
|
855 |
|
/** |
856 |
< |
* Returns {@code true} if the current thread is executing as a |
857 |
< |
* ForkJoinPool computation. |
856 |
> |
* Returns {@code true} if the current thread is a {@link |
857 |
> |
* ForkJoinWorkerThread} executing as a ForkJoinPool computation. |
858 |
|
* |
859 |
< |
* @return {@code true} if the current thread is executing as a |
860 |
< |
* ForkJoinPool computation, or false otherwise |
859 |
> |
* @return {@code true} if the current thread is a {@link |
860 |
> |
* ForkJoinWorkerThread} executing as a ForkJoinPool computation, |
861 |
> |
* or {@code false} otherwise |
862 |
|
*/ |
863 |
|
public static boolean inForkJoinPool() { |
864 |
|
return Thread.currentThread() instanceof ForkJoinWorkerThread; |
873 |
|
* were not, stolen. |
874 |
|
* |
875 |
|
* <p>This method may be invoked only from within {@code |
876 |
< |
* ForkJoinTask} computations (as may be determined using method |
876 |
> |
* ForkJoinPool} computations (as may be determined using method |
877 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
878 |
|
* result in exceptions or errors, possibly including {@code |
879 |
|
* ClassCastException}. |
892 |
|
* fork other tasks. |
893 |
|
* |
894 |
|
* <p>This method may be invoked only from within {@code |
895 |
< |
* ForkJoinTask} computations (as may be determined using method |
895 |
> |
* ForkJoinPool} computations (as may be determined using method |
896 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
897 |
|
* result in exceptions or errors, possibly including {@code |
898 |
|
* ClassCastException}. |
915 |
|
* exceeded. |
916 |
|
* |
917 |
|
* <p>This method may be invoked only from within {@code |
918 |
< |
* ForkJoinTask} computations (as may be determined using method |
918 |
> |
* ForkJoinPool} computations (as may be determined using method |
919 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
920 |
|
* result in exceptions or errors, possibly including {@code |
921 |
|
* ClassCastException}. |
973 |
|
* otherwise. |
974 |
|
* |
975 |
|
* <p>This method may be invoked only from within {@code |
976 |
< |
* ForkJoinTask} computations (as may be determined using method |
976 |
> |
* ForkJoinPool} computations (as may be determined using method |
977 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
978 |
|
* result in exceptions or errors, possibly including {@code |
979 |
|
* ClassCastException}. |
992 |
|
* be useful otherwise. |
993 |
|
* |
994 |
|
* <p>This method may be invoked only from within {@code |
995 |
< |
* ForkJoinTask} computations (as may be determined using method |
995 |
> |
* ForkJoinPool} computations (as may be determined using method |
996 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
997 |
|
* result in exceptions or errors, possibly including {@code |
998 |
|
* ClassCastException}. |
1015 |
|
* otherwise. |
1016 |
|
* |
1017 |
|
* <p>This method may be invoked only from within {@code |
1018 |
< |
* ForkJoinTask} computations (as may be determined using method |
1018 |
> |
* ForkJoinPool} computations (as may be determined using method |
1019 |
|
* {@link #inForkJoinPool}). Attempts to invoke in other contexts |
1020 |
|
* result in exceptions or errors, possibly including {@code |
1021 |
|
* ClassCastException}. |
1125 |
|
private static final long serialVersionUID = -7721805057305804111L; |
1126 |
|
|
1127 |
|
/** |
1128 |
< |
* Saves the state to a stream. |
1128 |
> |
* Saves the state to a stream (that is, serializes it). |
1129 |
|
* |
1130 |
|
* @serialData the current run status and the exception thrown |
1131 |
|
* during execution, or {@code null} if none |
1138 |
|
} |
1139 |
|
|
1140 |
|
/** |
1141 |
< |
* Reconstitutes the instance from a stream. |
1141 |
> |
* Reconstitutes the instance from a stream (that is, deserializes it). |
1142 |
|
* |
1143 |
|
* @param s the stream |
1144 |
|
*/ |