1 |
/* |
2 |
* Written by Doug Lea with assistance from members of JCP JSR-166 |
3 |
* Expert Group and released to the public domain, as explained at |
4 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
5 |
*/ |
6 |
|
7 |
package java.util.concurrent; |
8 |
import java.util.function.Supplier; |
9 |
import java.util.function.Consumer; |
10 |
import java.util.function.BiConsumer; |
11 |
import java.util.function.Function; |
12 |
import java.util.function.BiFunction; |
13 |
import java.util.concurrent.Future; |
14 |
import java.util.concurrent.TimeUnit; |
15 |
import java.util.concurrent.ForkJoinPool; |
16 |
import java.util.concurrent.ForkJoinTask; |
17 |
import java.util.concurrent.Executor; |
18 |
import java.util.concurrent.ThreadLocalRandom; |
19 |
import java.util.concurrent.ExecutionException; |
20 |
import java.util.concurrent.TimeoutException; |
21 |
import java.util.concurrent.CancellationException; |
22 |
import java.util.concurrent.atomic.AtomicInteger; |
23 |
import java.util.concurrent.locks.LockSupport; |
24 |
|
25 |
/** |
26 |
* A {@link Future} that may be explicitly completed (setting its |
27 |
* value and status), and may include dependent functions and actions |
28 |
* that trigger upon its completion. |
29 |
* |
30 |
* <p>When two or more threads attempt to |
31 |
* {@link #complete complete}, |
32 |
* {@link #completeExceptionally completeExceptionally}, or |
33 |
* {@link #cancel cancel} |
34 |
* a CompletableFuture, only one of them succeeds. |
35 |
* |
36 |
* <p>Methods are available for adding dependents based on |
37 |
* user-provided Functions, Consumers, or Runnables. The appropriate |
38 |
* form to use depends on whether actions require arguments and/or |
39 |
* produce results. Completion of a dependent action will trigger the |
40 |
* completion of another CompletableFuture. Actions may also be |
41 |
* triggered after either or both the current and another |
42 |
* CompletableFuture complete. Multiple CompletableFutures may also |
43 |
* be grouped as one using {@link #anyOf(CompletableFuture...)} and |
44 |
* {@link #allOf(CompletableFuture...)}. |
45 |
* |
46 |
* <p>CompletableFutures themselves do not execute asynchronously. |
47 |
* However, actions supplied for dependent completions of another |
48 |
* CompletableFuture may do so, depending on whether they are provided |
49 |
* via one of the <em>async</em> methods (that is, methods with names |
50 |
* of the form <tt><var>xxx</var>Async</tt>). The <em>async</em> |
51 |
* methods provide a way to commence asynchronous processing of an |
52 |
* action using either a given {@link Executor} or by default the |
53 |
* {@link ForkJoinPool#commonPool()}. To simplify monitoring, |
54 |
* debugging, and tracking, all generated asynchronous tasks are |
55 |
* instances of the marker interface {@link AsynchronousCompletionTask}. |
56 |
* |
57 |
* <p>Actions supplied for dependent completions of <em>non-async</em> |
58 |
* methods may be performed by the thread that completes the current |
59 |
* CompletableFuture, or by any other caller of these methods. There |
60 |
* are no guarantees about the order of processing completions unless |
61 |
* constrained by these methods. |
62 |
* |
63 |
* <p>Since (unlike {@link FutureTask}) this class has no direct |
64 |
* control over the computation that causes it to be completed, |
65 |
* cancellation is treated as just another form of exceptional completion. |
66 |
* Method {@link #cancel cancel} has the same effect as |
67 |
* {@code completeExceptionally(new CancellationException())}. |
68 |
* |
69 |
* <p>Upon exceptional completion (including cancellation), or when a |
70 |
* completion entails an additional computation which terminates |
71 |
* abruptly with an (unchecked) exception or error, then all of their |
72 |
* dependent completions (and their dependents in turn) generally act |
73 |
* as {@code completeExceptionally} with a {@link CompletionException} |
74 |
* holding that exception as its cause. However, the {@link |
75 |
* #exceptionally exceptionally} and {@link #handle handle} |
76 |
* completions <em>are</em> able to handle exceptional completions of |
77 |
* the CompletableFutures they depend on. |
78 |
* |
79 |
* <p>In case of exceptional completion with a CompletionException, |
80 |
* methods {@link #get()} and {@link #get(long, TimeUnit)} throw an |
81 |
* {@link ExecutionException} with the same cause as held in the |
82 |
* corresponding CompletionException. However, in these cases, |
83 |
* methods {@link #join()} and {@link #getNow} throw the |
84 |
* CompletionException, which simplifies usage. |
85 |
* |
86 |
* <p>Arguments used to pass a completion result (that is, for parameters |
87 |
* of type {@code T}) may be null, but passing a null value for any other |
88 |
* parameter will result in a {@link NullPointerException} being thrown. |
89 |
* |
90 |
* @author Doug Lea |
91 |
* @since 1.8 |
92 |
*/ |
93 |
public class CompletableFuture<T> implements Future<T> { |
94 |
|
95 |
/* |
96 |
* Overview: |
97 |
* |
98 |
* 1. Non-nullness of field result (set via CAS) indicates done. |
99 |
* An AltResult is used to box null as a result, as well as to |
100 |
* hold exceptions. Using a single field makes completion fast |
101 |
* and simple to detect and trigger, at the expense of a lot of |
102 |
* encoding and decoding that infiltrates many methods. One minor |
103 |
* simplification relies on the (static) NIL (to box null results) |
104 |
* being the only AltResult with a null exception field, so we |
105 |
* don't usually need explicit comparisons with NIL. The CF |
106 |
* exception propagation mechanics surrounding decoding rely on |
107 |
* unchecked casts of decoded results really being unchecked, |
108 |
* where user type errors are caught at point of use, as is |
109 |
* currently the case in Java. These are highlighted by using |
110 |
* SuppressWarnings-annotated temporaries. |
111 |
* |
112 |
* 2. Waiters are held in a Treiber stack similar to the one used |
113 |
* in FutureTask, Phaser, and SynchronousQueue. See their |
114 |
* internal documentation for algorithmic details. |
115 |
* |
116 |
* 3. Completions are also kept in a list/stack, and pulled off |
117 |
* and run when completion is triggered. (We could even use the |
118 |
* same stack as for waiters, but would give up the potential |
119 |
* parallelism obtained because woken waiters help release/run |
120 |
* others -- see method postComplete). Because post-processing |
121 |
* may race with direct calls, class Completion opportunistically |
122 |
* extends AtomicInteger so callers can claim the action via |
123 |
* compareAndSet(0, 1). The Completion.run methods are all |
124 |
* written a boringly similar uniform way (that sometimes includes |
125 |
* unnecessary-looking checks, kept to maintain uniformity). |
126 |
* There are enough dimensions upon which they differ that |
127 |
* attempts to factor commonalities while maintaining efficiency |
128 |
* require more lines of code than they would save. |
129 |
* |
130 |
* 4. The exported then/and/or methods do support a bit of |
131 |
* factoring (see doThenApply etc). They must cope with the |
132 |
* intrinsic races surrounding addition of a dependent action |
133 |
* versus performing the action directly because the task is |
134 |
* already complete. For example, a CF may not be complete upon |
135 |
* entry, so a dependent completion is added, but by the time it |
136 |
* is added, the target CF is complete, so must be directly |
137 |
* executed. This is all done while avoiding unnecessary object |
138 |
* construction in safe-bypass cases. |
139 |
*/ |
140 |
|
141 |
// preliminaries |
142 |
|
143 |
static final class AltResult { |
144 |
final Throwable ex; // null only for NIL |
145 |
AltResult(Throwable ex) { this.ex = ex; } |
146 |
} |
147 |
|
148 |
static final AltResult NIL = new AltResult(null); |
149 |
|
150 |
// Fields |
151 |
|
152 |
volatile Object result; // Either the result or boxed AltResult |
153 |
volatile WaitNode waiters; // Treiber stack of threads blocked on get() |
154 |
volatile CompletionNode completions; // list (Treiber stack) of completions |
155 |
|
156 |
// Basic utilities for triggering and processing completions |
157 |
|
158 |
/** |
159 |
* Removes and signals all waiting threads and runs all completions. |
160 |
*/ |
161 |
final void postComplete() { |
162 |
WaitNode q; Thread t; |
163 |
while ((q = waiters) != null) { |
164 |
if (UNSAFE.compareAndSwapObject(this, WAITERS, q, q.next) && |
165 |
(t = q.thread) != null) { |
166 |
q.thread = null; |
167 |
LockSupport.unpark(t); |
168 |
} |
169 |
} |
170 |
|
171 |
CompletionNode h; Completion c; |
172 |
while ((h = completions) != null) { |
173 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, h, h.next) && |
174 |
(c = h.completion) != null) |
175 |
c.run(); |
176 |
} |
177 |
} |
178 |
|
179 |
/** |
180 |
* Triggers completion with the encoding of the given arguments: |
181 |
* if the exception is non-null, encodes it as a wrapped |
182 |
* CompletionException unless it is one already. Otherwise uses |
183 |
* the given result, boxed as NIL if null. |
184 |
*/ |
185 |
final void internalComplete(T v, Throwable ex) { |
186 |
if (result == null) |
187 |
UNSAFE.compareAndSwapObject |
188 |
(this, RESULT, null, |
189 |
(ex == null) ? (v == null) ? NIL : v : |
190 |
new AltResult((ex instanceof CompletionException) ? ex : |
191 |
new CompletionException(ex))); |
192 |
postComplete(); // help out even if not triggered |
193 |
} |
194 |
|
195 |
/** |
196 |
* If triggered, helps release and/or process completions. |
197 |
*/ |
198 |
final void helpPostComplete() { |
199 |
if (result != null) |
200 |
postComplete(); |
201 |
} |
202 |
|
203 |
/* ------------- waiting for completions -------------- */ |
204 |
|
205 |
/** Number of processors, for spin control */ |
206 |
static final int NCPU = Runtime.getRuntime().availableProcessors(); |
207 |
|
208 |
/** |
209 |
* Heuristic spin value for waitingGet() before blocking on |
210 |
* multiprocessors |
211 |
*/ |
212 |
static final int SPINS = (NCPU > 1) ? 1 << 8 : 0; |
213 |
|
214 |
/** |
215 |
* Linked nodes to record waiting threads in a Treiber stack. See |
216 |
* other classes such as Phaser and SynchronousQueue for more |
217 |
* detailed explanation. This class implements ManagedBlocker to |
218 |
* avoid starvation when blocking actions pile up in |
219 |
* ForkJoinPools. |
220 |
*/ |
221 |
static final class WaitNode implements ForkJoinPool.ManagedBlocker { |
222 |
long nanos; // wait time if timed |
223 |
final long deadline; // non-zero if timed |
224 |
volatile int interruptControl; // > 0: interruptible, < 0: interrupted |
225 |
volatile Thread thread; |
226 |
volatile WaitNode next; |
227 |
WaitNode(boolean interruptible, long nanos, long deadline) { |
228 |
this.thread = Thread.currentThread(); |
229 |
this.interruptControl = interruptible ? 1 : 0; |
230 |
this.nanos = nanos; |
231 |
this.deadline = deadline; |
232 |
} |
233 |
public boolean isReleasable() { |
234 |
if (thread == null) |
235 |
return true; |
236 |
if (Thread.interrupted()) { |
237 |
int i = interruptControl; |
238 |
interruptControl = -1; |
239 |
if (i > 0) |
240 |
return true; |
241 |
} |
242 |
if (deadline != 0L && |
243 |
(nanos <= 0L || (nanos = deadline - System.nanoTime()) <= 0L)) { |
244 |
thread = null; |
245 |
return true; |
246 |
} |
247 |
return false; |
248 |
} |
249 |
public boolean block() { |
250 |
if (isReleasable()) |
251 |
return true; |
252 |
else if (deadline == 0L) |
253 |
LockSupport.park(this); |
254 |
else if (nanos > 0L) |
255 |
LockSupport.parkNanos(this, nanos); |
256 |
return isReleasable(); |
257 |
} |
258 |
} |
259 |
|
260 |
/** |
261 |
* Returns raw result after waiting, or null if interruptible and |
262 |
* interrupted. |
263 |
*/ |
264 |
private Object waitingGet(boolean interruptible) { |
265 |
WaitNode q = null; |
266 |
boolean queued = false; |
267 |
int spins = SPINS; |
268 |
for (Object r;;) { |
269 |
if ((r = result) != null) { |
270 |
if (q != null) { // suppress unpark |
271 |
q.thread = null; |
272 |
if (q.interruptControl < 0) { |
273 |
if (interruptible) { |
274 |
removeWaiter(q); |
275 |
return null; |
276 |
} |
277 |
Thread.currentThread().interrupt(); |
278 |
} |
279 |
} |
280 |
postComplete(); // help release others |
281 |
return r; |
282 |
} |
283 |
else if (spins > 0) { |
284 |
int rnd = ThreadLocalRandom.nextSecondarySeed(); |
285 |
if (rnd == 0) |
286 |
rnd = ThreadLocalRandom.current().nextInt(); |
287 |
if (rnd >= 0) |
288 |
--spins; |
289 |
} |
290 |
else if (q == null) |
291 |
q = new WaitNode(interruptible, 0L, 0L); |
292 |
else if (!queued) |
293 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
294 |
q.next = waiters, q); |
295 |
else if (interruptible && q.interruptControl < 0) { |
296 |
removeWaiter(q); |
297 |
return null; |
298 |
} |
299 |
else if (q.thread != null && result == null) { |
300 |
try { |
301 |
ForkJoinPool.managedBlock(q); |
302 |
} catch (InterruptedException ex) { |
303 |
q.interruptControl = -1; |
304 |
} |
305 |
} |
306 |
} |
307 |
} |
308 |
|
309 |
/** |
310 |
* Awaits completion or aborts on interrupt or timeout. |
311 |
* |
312 |
* @param nanos time to wait |
313 |
* @return raw result |
314 |
*/ |
315 |
private Object timedAwaitDone(long nanos) |
316 |
throws InterruptedException, TimeoutException { |
317 |
WaitNode q = null; |
318 |
boolean queued = false; |
319 |
for (Object r;;) { |
320 |
if ((r = result) != null) { |
321 |
if (q != null) { |
322 |
q.thread = null; |
323 |
if (q.interruptControl < 0) { |
324 |
removeWaiter(q); |
325 |
throw new InterruptedException(); |
326 |
} |
327 |
} |
328 |
postComplete(); |
329 |
return r; |
330 |
} |
331 |
else if (q == null) { |
332 |
if (nanos <= 0L) |
333 |
throw new TimeoutException(); |
334 |
long d = System.nanoTime() + nanos; |
335 |
q = new WaitNode(true, nanos, d == 0L ? 1L : d); // avoid 0 |
336 |
} |
337 |
else if (!queued) |
338 |
queued = UNSAFE.compareAndSwapObject(this, WAITERS, |
339 |
q.next = waiters, q); |
340 |
else if (q.interruptControl < 0) { |
341 |
removeWaiter(q); |
342 |
throw new InterruptedException(); |
343 |
} |
344 |
else if (q.nanos <= 0L) { |
345 |
if (result == null) { |
346 |
removeWaiter(q); |
347 |
throw new TimeoutException(); |
348 |
} |
349 |
} |
350 |
else if (q.thread != null && result == null) { |
351 |
try { |
352 |
ForkJoinPool.managedBlock(q); |
353 |
} catch (InterruptedException ex) { |
354 |
q.interruptControl = -1; |
355 |
} |
356 |
} |
357 |
} |
358 |
} |
359 |
|
360 |
/** |
361 |
* Tries to unlink a timed-out or interrupted wait node to avoid |
362 |
* accumulating garbage. Internal nodes are simply unspliced |
363 |
* without CAS since it is harmless if they are traversed anyway |
364 |
* by releasers. To avoid effects of unsplicing from already |
365 |
* removed nodes, the list is retraversed in case of an apparent |
366 |
* race. This is slow when there are a lot of nodes, but we don't |
367 |
* expect lists to be long enough to outweigh higher-overhead |
368 |
* schemes. |
369 |
*/ |
370 |
private void removeWaiter(WaitNode node) { |
371 |
if (node != null) { |
372 |
node.thread = null; |
373 |
retry: |
374 |
for (;;) { // restart on removeWaiter race |
375 |
for (WaitNode pred = null, q = waiters, s; q != null; q = s) { |
376 |
s = q.next; |
377 |
if (q.thread != null) |
378 |
pred = q; |
379 |
else if (pred != null) { |
380 |
pred.next = s; |
381 |
if (pred.thread == null) // check for race |
382 |
continue retry; |
383 |
} |
384 |
else if (!UNSAFE.compareAndSwapObject(this, WAITERS, q, s)) |
385 |
continue retry; |
386 |
} |
387 |
break; |
388 |
} |
389 |
} |
390 |
} |
391 |
|
392 |
/* ------------- Async tasks -------------- */ |
393 |
|
394 |
/** |
395 |
* A marker interface identifying asynchronous tasks produced by |
396 |
* {@code async} methods. This may be useful for monitoring, |
397 |
* debugging, and tracking asynchronous activities. |
398 |
* |
399 |
* @since 1.8 |
400 |
*/ |
401 |
public static interface AsynchronousCompletionTask { |
402 |
} |
403 |
|
404 |
/** Base class can act as either FJ or plain Runnable */ |
405 |
abstract static class Async extends ForkJoinTask<Void> |
406 |
implements Runnable, AsynchronousCompletionTask { |
407 |
public final Void getRawResult() { return null; } |
408 |
public final void setRawResult(Void v) { } |
409 |
public final void run() { exec(); } |
410 |
} |
411 |
|
412 |
static final class AsyncRun extends Async { |
413 |
final Runnable fn; |
414 |
final CompletableFuture<Void> dst; |
415 |
AsyncRun(Runnable fn, CompletableFuture<Void> dst) { |
416 |
this.fn = fn; this.dst = dst; |
417 |
} |
418 |
public final boolean exec() { |
419 |
CompletableFuture<Void> d; Throwable ex; |
420 |
if ((d = this.dst) != null && d.result == null) { |
421 |
try { |
422 |
fn.run(); |
423 |
ex = null; |
424 |
} catch (Throwable rex) { |
425 |
ex = rex; |
426 |
} |
427 |
d.internalComplete(null, ex); |
428 |
} |
429 |
return true; |
430 |
} |
431 |
private static final long serialVersionUID = 5232453952276885070L; |
432 |
} |
433 |
|
434 |
static final class AsyncSupply<U> extends Async { |
435 |
final Supplier<U> fn; |
436 |
final CompletableFuture<U> dst; |
437 |
AsyncSupply(Supplier<U> fn, CompletableFuture<U> dst) { |
438 |
this.fn = fn; this.dst = dst; |
439 |
} |
440 |
public final boolean exec() { |
441 |
CompletableFuture<U> d; U u; Throwable ex; |
442 |
if ((d = this.dst) != null && d.result == null) { |
443 |
try { |
444 |
u = fn.get(); |
445 |
ex = null; |
446 |
} catch (Throwable rex) { |
447 |
ex = rex; |
448 |
u = null; |
449 |
} |
450 |
d.internalComplete(u, ex); |
451 |
} |
452 |
return true; |
453 |
} |
454 |
private static final long serialVersionUID = 5232453952276885070L; |
455 |
} |
456 |
|
457 |
static final class AsyncApply<T,U> extends Async { |
458 |
final T arg; |
459 |
final Function<? super T,? extends U> fn; |
460 |
final CompletableFuture<U> dst; |
461 |
AsyncApply(T arg, Function<? super T,? extends U> fn, |
462 |
CompletableFuture<U> dst) { |
463 |
this.arg = arg; this.fn = fn; this.dst = dst; |
464 |
} |
465 |
public final boolean exec() { |
466 |
CompletableFuture<U> d; U u; Throwable ex; |
467 |
if ((d = this.dst) != null && d.result == null) { |
468 |
try { |
469 |
u = fn.apply(arg); |
470 |
ex = null; |
471 |
} catch (Throwable rex) { |
472 |
ex = rex; |
473 |
u = null; |
474 |
} |
475 |
d.internalComplete(u, ex); |
476 |
} |
477 |
return true; |
478 |
} |
479 |
private static final long serialVersionUID = 5232453952276885070L; |
480 |
} |
481 |
|
482 |
static final class AsyncBiApply<T,U,V> extends Async { |
483 |
final T arg1; |
484 |
final U arg2; |
485 |
final BiFunction<? super T,? super U,? extends V> fn; |
486 |
final CompletableFuture<V> dst; |
487 |
AsyncBiApply(T arg1, U arg2, |
488 |
BiFunction<? super T,? super U,? extends V> fn, |
489 |
CompletableFuture<V> dst) { |
490 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
491 |
} |
492 |
public final boolean exec() { |
493 |
CompletableFuture<V> d; V v; Throwable ex; |
494 |
if ((d = this.dst) != null && d.result == null) { |
495 |
try { |
496 |
v = fn.apply(arg1, arg2); |
497 |
ex = null; |
498 |
} catch (Throwable rex) { |
499 |
ex = rex; |
500 |
v = null; |
501 |
} |
502 |
d.internalComplete(v, ex); |
503 |
} |
504 |
return true; |
505 |
} |
506 |
private static final long serialVersionUID = 5232453952276885070L; |
507 |
} |
508 |
|
509 |
static final class AsyncAccept<T> extends Async { |
510 |
final T arg; |
511 |
final Consumer<? super T> fn; |
512 |
final CompletableFuture<Void> dst; |
513 |
AsyncAccept(T arg, Consumer<? super T> fn, |
514 |
CompletableFuture<Void> dst) { |
515 |
this.arg = arg; this.fn = fn; this.dst = dst; |
516 |
} |
517 |
public final boolean exec() { |
518 |
CompletableFuture<Void> d; Throwable ex; |
519 |
if ((d = this.dst) != null && d.result == null) { |
520 |
try { |
521 |
fn.accept(arg); |
522 |
ex = null; |
523 |
} catch (Throwable rex) { |
524 |
ex = rex; |
525 |
} |
526 |
d.internalComplete(null, ex); |
527 |
} |
528 |
return true; |
529 |
} |
530 |
private static final long serialVersionUID = 5232453952276885070L; |
531 |
} |
532 |
|
533 |
static final class AsyncBiAccept<T,U> extends Async { |
534 |
final T arg1; |
535 |
final U arg2; |
536 |
final BiConsumer<? super T,? super U> fn; |
537 |
final CompletableFuture<Void> dst; |
538 |
AsyncBiAccept(T arg1, U arg2, |
539 |
BiConsumer<? super T,? super U> fn, |
540 |
CompletableFuture<Void> dst) { |
541 |
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst; |
542 |
} |
543 |
public final boolean exec() { |
544 |
CompletableFuture<Void> d; Throwable ex; |
545 |
if ((d = this.dst) != null && d.result == null) { |
546 |
try { |
547 |
fn.accept(arg1, arg2); |
548 |
ex = null; |
549 |
} catch (Throwable rex) { |
550 |
ex = rex; |
551 |
} |
552 |
d.internalComplete(null, ex); |
553 |
} |
554 |
return true; |
555 |
} |
556 |
private static final long serialVersionUID = 5232453952276885070L; |
557 |
} |
558 |
|
559 |
static final class AsyncCompose<T,U> extends Async { |
560 |
final T arg; |
561 |
final Function<? super T, CompletableFuture<U>> fn; |
562 |
final CompletableFuture<U> dst; |
563 |
AsyncCompose(T arg, |
564 |
Function<? super T, CompletableFuture<U>> fn, |
565 |
CompletableFuture<U> dst) { |
566 |
this.arg = arg; this.fn = fn; this.dst = dst; |
567 |
} |
568 |
public final boolean exec() { |
569 |
CompletableFuture<U> d, fr; U u; Throwable ex; |
570 |
if ((d = this.dst) != null && d.result == null) { |
571 |
try { |
572 |
fr = fn.apply(arg); |
573 |
ex = (fr == null) ? new NullPointerException() : null; |
574 |
} catch (Throwable rex) { |
575 |
ex = rex; |
576 |
fr = null; |
577 |
} |
578 |
if (ex != null) |
579 |
u = null; |
580 |
else { |
581 |
Object r = fr.result; |
582 |
if (r == null) |
583 |
r = fr.waitingGet(false); |
584 |
if (r instanceof AltResult) { |
585 |
ex = ((AltResult)r).ex; |
586 |
u = null; |
587 |
} |
588 |
else { |
589 |
@SuppressWarnings("unchecked") U ur = (U) r; |
590 |
u = ur; |
591 |
} |
592 |
} |
593 |
d.internalComplete(u, ex); |
594 |
} |
595 |
return true; |
596 |
} |
597 |
private static final long serialVersionUID = 5232453952276885070L; |
598 |
} |
599 |
|
600 |
/* ------------- Completions -------------- */ |
601 |
|
602 |
/** |
603 |
* Simple linked list nodes to record completions, used in |
604 |
* basically the same way as WaitNodes. (We separate nodes from |
605 |
* the Completions themselves mainly because for the And and Or |
606 |
* methods, the same Completion object resides in two lists.) |
607 |
*/ |
608 |
static final class CompletionNode { |
609 |
final Completion completion; |
610 |
volatile CompletionNode next; |
611 |
CompletionNode(Completion completion) { this.completion = completion; } |
612 |
} |
613 |
|
614 |
// Opportunistically subclass AtomicInteger to use compareAndSet to claim. |
615 |
abstract static class Completion extends AtomicInteger implements Runnable { |
616 |
} |
617 |
|
618 |
static final class ApplyCompletion<T,U> extends Completion { |
619 |
final CompletableFuture<? extends T> src; |
620 |
final Function<? super T,? extends U> fn; |
621 |
final CompletableFuture<U> dst; |
622 |
final Executor executor; |
623 |
ApplyCompletion(CompletableFuture<? extends T> src, |
624 |
Function<? super T,? extends U> fn, |
625 |
CompletableFuture<U> dst, Executor executor) { |
626 |
this.src = src; this.fn = fn; this.dst = dst; |
627 |
this.executor = executor; |
628 |
} |
629 |
public final void run() { |
630 |
final CompletableFuture<? extends T> a; |
631 |
final Function<? super T,? extends U> fn; |
632 |
final CompletableFuture<U> dst; |
633 |
Object r; T t; Throwable ex; |
634 |
if ((dst = this.dst) != null && |
635 |
(fn = this.fn) != null && |
636 |
(a = this.src) != null && |
637 |
(r = a.result) != null && |
638 |
compareAndSet(0, 1)) { |
639 |
if (r instanceof AltResult) { |
640 |
ex = ((AltResult)r).ex; |
641 |
t = null; |
642 |
} |
643 |
else { |
644 |
ex = null; |
645 |
@SuppressWarnings("unchecked") T tr = (T) r; |
646 |
t = tr; |
647 |
} |
648 |
Executor e = executor; |
649 |
U u = null; |
650 |
if (ex == null) { |
651 |
try { |
652 |
if (e != null) |
653 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
654 |
else |
655 |
u = fn.apply(t); |
656 |
} catch (Throwable rex) { |
657 |
ex = rex; |
658 |
} |
659 |
} |
660 |
if (e == null || ex != null) |
661 |
dst.internalComplete(u, ex); |
662 |
} |
663 |
} |
664 |
private static final long serialVersionUID = 5232453952276885070L; |
665 |
} |
666 |
|
667 |
static final class AcceptCompletion<T> extends Completion { |
668 |
final CompletableFuture<? extends T> src; |
669 |
final Consumer<? super T> fn; |
670 |
final CompletableFuture<Void> dst; |
671 |
final Executor executor; |
672 |
AcceptCompletion(CompletableFuture<? extends T> src, |
673 |
Consumer<? super T> fn, |
674 |
CompletableFuture<Void> dst, Executor executor) { |
675 |
this.src = src; this.fn = fn; this.dst = dst; |
676 |
this.executor = executor; |
677 |
} |
678 |
public final void run() { |
679 |
final CompletableFuture<? extends T> a; |
680 |
final Consumer<? super T> fn; |
681 |
final CompletableFuture<Void> dst; |
682 |
Object r; T t; Throwable ex; |
683 |
if ((dst = this.dst) != null && |
684 |
(fn = this.fn) != null && |
685 |
(a = this.src) != null && |
686 |
(r = a.result) != null && |
687 |
compareAndSet(0, 1)) { |
688 |
if (r instanceof AltResult) { |
689 |
ex = ((AltResult)r).ex; |
690 |
t = null; |
691 |
} |
692 |
else { |
693 |
ex = null; |
694 |
@SuppressWarnings("unchecked") T tr = (T) r; |
695 |
t = tr; |
696 |
} |
697 |
Executor e = executor; |
698 |
if (ex == null) { |
699 |
try { |
700 |
if (e != null) |
701 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
702 |
else |
703 |
fn.accept(t); |
704 |
} catch (Throwable rex) { |
705 |
ex = rex; |
706 |
} |
707 |
} |
708 |
if (e == null || ex != null) |
709 |
dst.internalComplete(null, ex); |
710 |
} |
711 |
} |
712 |
private static final long serialVersionUID = 5232453952276885070L; |
713 |
} |
714 |
|
715 |
static final class RunCompletion<T> extends Completion { |
716 |
final CompletableFuture<? extends T> src; |
717 |
final Runnable fn; |
718 |
final CompletableFuture<Void> dst; |
719 |
final Executor executor; |
720 |
RunCompletion(CompletableFuture<? extends T> src, |
721 |
Runnable fn, |
722 |
CompletableFuture<Void> dst, |
723 |
Executor executor) { |
724 |
this.src = src; this.fn = fn; this.dst = dst; |
725 |
this.executor = executor; |
726 |
} |
727 |
public final void run() { |
728 |
final CompletableFuture<? extends T> a; |
729 |
final Runnable fn; |
730 |
final CompletableFuture<Void> dst; |
731 |
Object r; Throwable ex; |
732 |
if ((dst = this.dst) != null && |
733 |
(fn = this.fn) != null && |
734 |
(a = this.src) != null && |
735 |
(r = a.result) != null && |
736 |
compareAndSet(0, 1)) { |
737 |
if (r instanceof AltResult) |
738 |
ex = ((AltResult)r).ex; |
739 |
else |
740 |
ex = null; |
741 |
Executor e = executor; |
742 |
if (ex == null) { |
743 |
try { |
744 |
if (e != null) |
745 |
e.execute(new AsyncRun(fn, dst)); |
746 |
else |
747 |
fn.run(); |
748 |
} catch (Throwable rex) { |
749 |
ex = rex; |
750 |
} |
751 |
} |
752 |
if (e == null || ex != null) |
753 |
dst.internalComplete(null, ex); |
754 |
} |
755 |
} |
756 |
private static final long serialVersionUID = 5232453952276885070L; |
757 |
} |
758 |
|
759 |
static final class BiApplyCompletion<T,U,V> extends Completion { |
760 |
final CompletableFuture<? extends T> src; |
761 |
final CompletableFuture<? extends U> snd; |
762 |
final BiFunction<? super T,? super U,? extends V> fn; |
763 |
final CompletableFuture<V> dst; |
764 |
final Executor executor; |
765 |
BiApplyCompletion(CompletableFuture<? extends T> src, |
766 |
CompletableFuture<? extends U> snd, |
767 |
BiFunction<? super T,? super U,? extends V> fn, |
768 |
CompletableFuture<V> dst, Executor executor) { |
769 |
this.src = src; this.snd = snd; |
770 |
this.fn = fn; this.dst = dst; |
771 |
this.executor = executor; |
772 |
} |
773 |
public final void run() { |
774 |
final CompletableFuture<? extends T> a; |
775 |
final CompletableFuture<? extends U> b; |
776 |
final BiFunction<? super T,? super U,? extends V> fn; |
777 |
final CompletableFuture<V> dst; |
778 |
Object r, s; T t; U u; Throwable ex; |
779 |
if ((dst = this.dst) != null && |
780 |
(fn = this.fn) != null && |
781 |
(a = this.src) != null && |
782 |
(r = a.result) != null && |
783 |
(b = this.snd) != null && |
784 |
(s = b.result) != null && |
785 |
compareAndSet(0, 1)) { |
786 |
if (r instanceof AltResult) { |
787 |
ex = ((AltResult)r).ex; |
788 |
t = null; |
789 |
} |
790 |
else { |
791 |
ex = null; |
792 |
@SuppressWarnings("unchecked") T tr = (T) r; |
793 |
t = tr; |
794 |
} |
795 |
if (ex != null) |
796 |
u = null; |
797 |
else if (s instanceof AltResult) { |
798 |
ex = ((AltResult)s).ex; |
799 |
u = null; |
800 |
} |
801 |
else { |
802 |
@SuppressWarnings("unchecked") U us = (U) s; |
803 |
u = us; |
804 |
} |
805 |
Executor e = executor; |
806 |
V v = null; |
807 |
if (ex == null) { |
808 |
try { |
809 |
if (e != null) |
810 |
e.execute(new AsyncBiApply<T,U,V>(t, u, fn, dst)); |
811 |
else |
812 |
v = fn.apply(t, u); |
813 |
} catch (Throwable rex) { |
814 |
ex = rex; |
815 |
} |
816 |
} |
817 |
if (e == null || ex != null) |
818 |
dst.internalComplete(v, ex); |
819 |
} |
820 |
} |
821 |
private static final long serialVersionUID = 5232453952276885070L; |
822 |
} |
823 |
|
824 |
static final class BiAcceptCompletion<T,U> extends Completion { |
825 |
final CompletableFuture<? extends T> src; |
826 |
final CompletableFuture<? extends U> snd; |
827 |
final BiConsumer<? super T,? super U> fn; |
828 |
final CompletableFuture<Void> dst; |
829 |
final Executor executor; |
830 |
BiAcceptCompletion(CompletableFuture<? extends T> src, |
831 |
CompletableFuture<? extends U> snd, |
832 |
BiConsumer<? super T,? super U> fn, |
833 |
CompletableFuture<Void> dst, Executor executor) { |
834 |
this.src = src; this.snd = snd; |
835 |
this.fn = fn; this.dst = dst; |
836 |
this.executor = executor; |
837 |
} |
838 |
public final void run() { |
839 |
final CompletableFuture<? extends T> a; |
840 |
final CompletableFuture<? extends U> b; |
841 |
final BiConsumer<? super T,? super U> fn; |
842 |
final CompletableFuture<Void> dst; |
843 |
Object r, s; T t; U u; Throwable ex; |
844 |
if ((dst = this.dst) != null && |
845 |
(fn = this.fn) != null && |
846 |
(a = this.src) != null && |
847 |
(r = a.result) != null && |
848 |
(b = this.snd) != null && |
849 |
(s = b.result) != null && |
850 |
compareAndSet(0, 1)) { |
851 |
if (r instanceof AltResult) { |
852 |
ex = ((AltResult)r).ex; |
853 |
t = null; |
854 |
} |
855 |
else { |
856 |
ex = null; |
857 |
@SuppressWarnings("unchecked") T tr = (T) r; |
858 |
t = tr; |
859 |
} |
860 |
if (ex != null) |
861 |
u = null; |
862 |
else if (s instanceof AltResult) { |
863 |
ex = ((AltResult)s).ex; |
864 |
u = null; |
865 |
} |
866 |
else { |
867 |
@SuppressWarnings("unchecked") U us = (U) s; |
868 |
u = us; |
869 |
} |
870 |
Executor e = executor; |
871 |
if (ex == null) { |
872 |
try { |
873 |
if (e != null) |
874 |
e.execute(new AsyncBiAccept<T,U>(t, u, fn, dst)); |
875 |
else |
876 |
fn.accept(t, u); |
877 |
} catch (Throwable rex) { |
878 |
ex = rex; |
879 |
} |
880 |
} |
881 |
if (e == null || ex != null) |
882 |
dst.internalComplete(null, ex); |
883 |
} |
884 |
} |
885 |
private static final long serialVersionUID = 5232453952276885070L; |
886 |
} |
887 |
|
888 |
static final class BiRunCompletion<T> extends Completion { |
889 |
final CompletableFuture<? extends T> src; |
890 |
final CompletableFuture<?> snd; |
891 |
final Runnable fn; |
892 |
final CompletableFuture<Void> dst; |
893 |
final Executor executor; |
894 |
BiRunCompletion(CompletableFuture<? extends T> src, |
895 |
CompletableFuture<?> snd, |
896 |
Runnable fn, |
897 |
CompletableFuture<Void> dst, Executor executor) { |
898 |
this.src = src; this.snd = snd; |
899 |
this.fn = fn; this.dst = dst; |
900 |
this.executor = executor; |
901 |
} |
902 |
public final void run() { |
903 |
final CompletableFuture<? extends T> a; |
904 |
final CompletableFuture<?> b; |
905 |
final Runnable fn; |
906 |
final CompletableFuture<Void> dst; |
907 |
Object r, s; Throwable ex; |
908 |
if ((dst = this.dst) != null && |
909 |
(fn = this.fn) != null && |
910 |
(a = this.src) != null && |
911 |
(r = a.result) != null && |
912 |
(b = this.snd) != null && |
913 |
(s = b.result) != null && |
914 |
compareAndSet(0, 1)) { |
915 |
if (r instanceof AltResult) |
916 |
ex = ((AltResult)r).ex; |
917 |
else |
918 |
ex = null; |
919 |
if (ex == null && (s instanceof AltResult)) |
920 |
ex = ((AltResult)s).ex; |
921 |
Executor e = executor; |
922 |
if (ex == null) { |
923 |
try { |
924 |
if (e != null) |
925 |
e.execute(new AsyncRun(fn, dst)); |
926 |
else |
927 |
fn.run(); |
928 |
} catch (Throwable rex) { |
929 |
ex = rex; |
930 |
} |
931 |
} |
932 |
if (e == null || ex != null) |
933 |
dst.internalComplete(null, ex); |
934 |
} |
935 |
} |
936 |
private static final long serialVersionUID = 5232453952276885070L; |
937 |
} |
938 |
|
939 |
static final class AndCompletion extends Completion { |
940 |
final CompletableFuture<?> src; |
941 |
final CompletableFuture<?> snd; |
942 |
final CompletableFuture<Void> dst; |
943 |
AndCompletion(CompletableFuture<?> src, |
944 |
CompletableFuture<?> snd, |
945 |
CompletableFuture<Void> dst) { |
946 |
this.src = src; this.snd = snd; this.dst = dst; |
947 |
} |
948 |
public final void run() { |
949 |
final CompletableFuture<?> a; |
950 |
final CompletableFuture<?> b; |
951 |
final CompletableFuture<Void> dst; |
952 |
Object r, s; Throwable ex; |
953 |
if ((dst = this.dst) != null && |
954 |
(a = this.src) != null && |
955 |
(r = a.result) != null && |
956 |
(b = this.snd) != null && |
957 |
(s = b.result) != null && |
958 |
compareAndSet(0, 1)) { |
959 |
if (r instanceof AltResult) |
960 |
ex = ((AltResult)r).ex; |
961 |
else |
962 |
ex = null; |
963 |
if (ex == null && (s instanceof AltResult)) |
964 |
ex = ((AltResult)s).ex; |
965 |
dst.internalComplete(null, ex); |
966 |
} |
967 |
} |
968 |
private static final long serialVersionUID = 5232453952276885070L; |
969 |
} |
970 |
|
971 |
static final class OrApplyCompletion<T,U> extends Completion { |
972 |
final CompletableFuture<? extends T> src; |
973 |
final CompletableFuture<? extends T> snd; |
974 |
final Function<? super T,? extends U> fn; |
975 |
final CompletableFuture<U> dst; |
976 |
final Executor executor; |
977 |
OrApplyCompletion(CompletableFuture<? extends T> src, |
978 |
CompletableFuture<? extends T> snd, |
979 |
Function<? super T,? extends U> fn, |
980 |
CompletableFuture<U> dst, Executor executor) { |
981 |
this.src = src; this.snd = snd; |
982 |
this.fn = fn; this.dst = dst; |
983 |
this.executor = executor; |
984 |
} |
985 |
public final void run() { |
986 |
final CompletableFuture<? extends T> a; |
987 |
final CompletableFuture<? extends T> b; |
988 |
final Function<? super T,? extends U> fn; |
989 |
final CompletableFuture<U> dst; |
990 |
Object r; T t; Throwable ex; |
991 |
if ((dst = this.dst) != null && |
992 |
(fn = this.fn) != null && |
993 |
(((a = this.src) != null && (r = a.result) != null) || |
994 |
((b = this.snd) != null && (r = b.result) != null)) && |
995 |
compareAndSet(0, 1)) { |
996 |
if (r instanceof AltResult) { |
997 |
ex = ((AltResult)r).ex; |
998 |
t = null; |
999 |
} |
1000 |
else { |
1001 |
ex = null; |
1002 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1003 |
t = tr; |
1004 |
} |
1005 |
Executor e = executor; |
1006 |
U u = null; |
1007 |
if (ex == null) { |
1008 |
try { |
1009 |
if (e != null) |
1010 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
1011 |
else |
1012 |
u = fn.apply(t); |
1013 |
} catch (Throwable rex) { |
1014 |
ex = rex; |
1015 |
} |
1016 |
} |
1017 |
if (e == null || ex != null) |
1018 |
dst.internalComplete(u, ex); |
1019 |
} |
1020 |
} |
1021 |
private static final long serialVersionUID = 5232453952276885070L; |
1022 |
} |
1023 |
|
1024 |
static final class OrAcceptCompletion<T> extends Completion { |
1025 |
final CompletableFuture<? extends T> src; |
1026 |
final CompletableFuture<? extends T> snd; |
1027 |
final Consumer<? super T> fn; |
1028 |
final CompletableFuture<Void> dst; |
1029 |
final Executor executor; |
1030 |
OrAcceptCompletion(CompletableFuture<? extends T> src, |
1031 |
CompletableFuture<? extends T> snd, |
1032 |
Consumer<? super T> fn, |
1033 |
CompletableFuture<Void> dst, Executor executor) { |
1034 |
this.src = src; this.snd = snd; |
1035 |
this.fn = fn; this.dst = dst; |
1036 |
this.executor = executor; |
1037 |
} |
1038 |
public final void run() { |
1039 |
final CompletableFuture<? extends T> a; |
1040 |
final CompletableFuture<? extends T> b; |
1041 |
final Consumer<? super T> fn; |
1042 |
final CompletableFuture<Void> dst; |
1043 |
Object r; T t; Throwable ex; |
1044 |
if ((dst = this.dst) != null && |
1045 |
(fn = this.fn) != null && |
1046 |
(((a = this.src) != null && (r = a.result) != null) || |
1047 |
((b = this.snd) != null && (r = b.result) != null)) && |
1048 |
compareAndSet(0, 1)) { |
1049 |
if (r instanceof AltResult) { |
1050 |
ex = ((AltResult)r).ex; |
1051 |
t = null; |
1052 |
} |
1053 |
else { |
1054 |
ex = null; |
1055 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1056 |
t = tr; |
1057 |
} |
1058 |
Executor e = executor; |
1059 |
if (ex == null) { |
1060 |
try { |
1061 |
if (e != null) |
1062 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
1063 |
else |
1064 |
fn.accept(t); |
1065 |
} catch (Throwable rex) { |
1066 |
ex = rex; |
1067 |
} |
1068 |
} |
1069 |
if (e == null || ex != null) |
1070 |
dst.internalComplete(null, ex); |
1071 |
} |
1072 |
} |
1073 |
private static final long serialVersionUID = 5232453952276885070L; |
1074 |
} |
1075 |
|
1076 |
static final class OrRunCompletion<T> extends Completion { |
1077 |
final CompletableFuture<? extends T> src; |
1078 |
final CompletableFuture<?> snd; |
1079 |
final Runnable fn; |
1080 |
final CompletableFuture<Void> dst; |
1081 |
final Executor executor; |
1082 |
OrRunCompletion(CompletableFuture<? extends T> src, |
1083 |
CompletableFuture<?> snd, |
1084 |
Runnable fn, |
1085 |
CompletableFuture<Void> dst, Executor executor) { |
1086 |
this.src = src; this.snd = snd; |
1087 |
this.fn = fn; this.dst = dst; |
1088 |
this.executor = executor; |
1089 |
} |
1090 |
public final void run() { |
1091 |
final CompletableFuture<? extends T> a; |
1092 |
final CompletableFuture<?> b; |
1093 |
final Runnable fn; |
1094 |
final CompletableFuture<Void> dst; |
1095 |
Object r; Throwable ex; |
1096 |
if ((dst = this.dst) != null && |
1097 |
(fn = this.fn) != null && |
1098 |
(((a = this.src) != null && (r = a.result) != null) || |
1099 |
((b = this.snd) != null && (r = b.result) != null)) && |
1100 |
compareAndSet(0, 1)) { |
1101 |
if (r instanceof AltResult) |
1102 |
ex = ((AltResult)r).ex; |
1103 |
else |
1104 |
ex = null; |
1105 |
Executor e = executor; |
1106 |
if (ex == null) { |
1107 |
try { |
1108 |
if (e != null) |
1109 |
e.execute(new AsyncRun(fn, dst)); |
1110 |
else |
1111 |
fn.run(); |
1112 |
} catch (Throwable rex) { |
1113 |
ex = rex; |
1114 |
} |
1115 |
} |
1116 |
if (e == null || ex != null) |
1117 |
dst.internalComplete(null, ex); |
1118 |
} |
1119 |
} |
1120 |
private static final long serialVersionUID = 5232453952276885070L; |
1121 |
} |
1122 |
|
1123 |
static final class OrCompletion extends Completion { |
1124 |
final CompletableFuture<?> src; |
1125 |
final CompletableFuture<?> snd; |
1126 |
final CompletableFuture<Object> dst; |
1127 |
OrCompletion(CompletableFuture<?> src, |
1128 |
CompletableFuture<?> snd, |
1129 |
CompletableFuture<Object> dst) { |
1130 |
this.src = src; this.snd = snd; this.dst = dst; |
1131 |
} |
1132 |
public final void run() { |
1133 |
final CompletableFuture<?> a; |
1134 |
final CompletableFuture<?> b; |
1135 |
final CompletableFuture<Object> dst; |
1136 |
Object r, t; Throwable ex; |
1137 |
if ((dst = this.dst) != null && |
1138 |
(((a = this.src) != null && (r = a.result) != null) || |
1139 |
((b = this.snd) != null && (r = b.result) != null)) && |
1140 |
compareAndSet(0, 1)) { |
1141 |
if (r instanceof AltResult) { |
1142 |
ex = ((AltResult)r).ex; |
1143 |
t = null; |
1144 |
} |
1145 |
else { |
1146 |
ex = null; |
1147 |
t = r; |
1148 |
} |
1149 |
dst.internalComplete(t, ex); |
1150 |
} |
1151 |
} |
1152 |
private static final long serialVersionUID = 5232453952276885070L; |
1153 |
} |
1154 |
|
1155 |
static final class ExceptionCompletion<T> extends Completion { |
1156 |
final CompletableFuture<? extends T> src; |
1157 |
final Function<? super Throwable, ? extends T> fn; |
1158 |
final CompletableFuture<T> dst; |
1159 |
ExceptionCompletion(CompletableFuture<? extends T> src, |
1160 |
Function<? super Throwable, ? extends T> fn, |
1161 |
CompletableFuture<T> dst) { |
1162 |
this.src = src; this.fn = fn; this.dst = dst; |
1163 |
} |
1164 |
public final void run() { |
1165 |
final CompletableFuture<? extends T> a; |
1166 |
final Function<? super Throwable, ? extends T> fn; |
1167 |
final CompletableFuture<T> dst; |
1168 |
Object r; T t = null; Throwable ex, dx = null; |
1169 |
if ((dst = this.dst) != null && |
1170 |
(fn = this.fn) != null && |
1171 |
(a = this.src) != null && |
1172 |
(r = a.result) != null && |
1173 |
compareAndSet(0, 1)) { |
1174 |
if ((r instanceof AltResult) && |
1175 |
(ex = ((AltResult)r).ex) != null) { |
1176 |
try { |
1177 |
t = fn.apply(ex); |
1178 |
} catch (Throwable rex) { |
1179 |
dx = rex; |
1180 |
} |
1181 |
} |
1182 |
else { |
1183 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1184 |
t = tr; |
1185 |
} |
1186 |
dst.internalComplete(t, dx); |
1187 |
} |
1188 |
} |
1189 |
private static final long serialVersionUID = 5232453952276885070L; |
1190 |
} |
1191 |
|
1192 |
static final class ThenCopy<T> extends Completion { |
1193 |
final CompletableFuture<?> src; |
1194 |
final CompletableFuture<T> dst; |
1195 |
ThenCopy(CompletableFuture<?> src, |
1196 |
CompletableFuture<T> dst) { |
1197 |
this.src = src; this.dst = dst; |
1198 |
} |
1199 |
public final void run() { |
1200 |
final CompletableFuture<?> a; |
1201 |
final CompletableFuture<T> dst; |
1202 |
Object r; T t; Throwable ex; |
1203 |
if ((dst = this.dst) != null && |
1204 |
(a = this.src) != null && |
1205 |
(r = a.result) != null && |
1206 |
compareAndSet(0, 1)) { |
1207 |
if (r instanceof AltResult) { |
1208 |
ex = ((AltResult)r).ex; |
1209 |
t = null; |
1210 |
} |
1211 |
else { |
1212 |
ex = null; |
1213 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1214 |
t = tr; |
1215 |
} |
1216 |
dst.internalComplete(t, ex); |
1217 |
} |
1218 |
} |
1219 |
private static final long serialVersionUID = 5232453952276885070L; |
1220 |
} |
1221 |
|
1222 |
// version of ThenCopy for CompletableFuture<Void> dst |
1223 |
static final class ThenPropagate extends Completion { |
1224 |
final CompletableFuture<?> src; |
1225 |
final CompletableFuture<Void> dst; |
1226 |
ThenPropagate(CompletableFuture<?> src, |
1227 |
CompletableFuture<Void> dst) { |
1228 |
this.src = src; this.dst = dst; |
1229 |
} |
1230 |
public final void run() { |
1231 |
final CompletableFuture<?> a; |
1232 |
final CompletableFuture<Void> dst; |
1233 |
Object r; Throwable ex; |
1234 |
if ((dst = this.dst) != null && |
1235 |
(a = this.src) != null && |
1236 |
(r = a.result) != null && |
1237 |
compareAndSet(0, 1)) { |
1238 |
if (r instanceof AltResult) |
1239 |
ex = ((AltResult)r).ex; |
1240 |
else |
1241 |
ex = null; |
1242 |
dst.internalComplete(null, ex); |
1243 |
} |
1244 |
} |
1245 |
private static final long serialVersionUID = 5232453952276885070L; |
1246 |
} |
1247 |
|
1248 |
static final class HandleCompletion<T,U> extends Completion { |
1249 |
final CompletableFuture<? extends T> src; |
1250 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1251 |
final CompletableFuture<U> dst; |
1252 |
HandleCompletion(CompletableFuture<? extends T> src, |
1253 |
BiFunction<? super T, Throwable, ? extends U> fn, |
1254 |
CompletableFuture<U> dst) { |
1255 |
this.src = src; this.fn = fn; this.dst = dst; |
1256 |
} |
1257 |
public final void run() { |
1258 |
final CompletableFuture<? extends T> a; |
1259 |
final BiFunction<? super T, Throwable, ? extends U> fn; |
1260 |
final CompletableFuture<U> dst; |
1261 |
Object r; T t; Throwable ex; |
1262 |
if ((dst = this.dst) != null && |
1263 |
(fn = this.fn) != null && |
1264 |
(a = this.src) != null && |
1265 |
(r = a.result) != null && |
1266 |
compareAndSet(0, 1)) { |
1267 |
if (r instanceof AltResult) { |
1268 |
ex = ((AltResult)r).ex; |
1269 |
t = null; |
1270 |
} |
1271 |
else { |
1272 |
ex = null; |
1273 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1274 |
t = tr; |
1275 |
} |
1276 |
U u = null; Throwable dx = null; |
1277 |
try { |
1278 |
u = fn.apply(t, ex); |
1279 |
} catch (Throwable rex) { |
1280 |
dx = rex; |
1281 |
} |
1282 |
dst.internalComplete(u, dx); |
1283 |
} |
1284 |
} |
1285 |
private static final long serialVersionUID = 5232453952276885070L; |
1286 |
} |
1287 |
|
1288 |
static final class ComposeCompletion<T,U> extends Completion { |
1289 |
final CompletableFuture<? extends T> src; |
1290 |
final Function<? super T, CompletableFuture<U>> fn; |
1291 |
final CompletableFuture<U> dst; |
1292 |
final Executor executor; |
1293 |
ComposeCompletion(CompletableFuture<? extends T> src, |
1294 |
Function<? super T, CompletableFuture<U>> fn, |
1295 |
CompletableFuture<U> dst, Executor executor) { |
1296 |
this.src = src; this.fn = fn; this.dst = dst; |
1297 |
this.executor = executor; |
1298 |
} |
1299 |
public final void run() { |
1300 |
final CompletableFuture<? extends T> a; |
1301 |
final Function<? super T, CompletableFuture<U>> fn; |
1302 |
final CompletableFuture<U> dst; |
1303 |
Object r; T t; Throwable ex; Executor e; |
1304 |
if ((dst = this.dst) != null && |
1305 |
(fn = this.fn) != null && |
1306 |
(a = this.src) != null && |
1307 |
(r = a.result) != null && |
1308 |
compareAndSet(0, 1)) { |
1309 |
if (r instanceof AltResult) { |
1310 |
ex = ((AltResult)r).ex; |
1311 |
t = null; |
1312 |
} |
1313 |
else { |
1314 |
ex = null; |
1315 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1316 |
t = tr; |
1317 |
} |
1318 |
CompletableFuture<U> c = null; |
1319 |
U u = null; |
1320 |
boolean complete = false; |
1321 |
if (ex == null) { |
1322 |
if ((e = executor) != null) |
1323 |
e.execute(new AsyncCompose<T,U>(t, fn, dst)); |
1324 |
else { |
1325 |
try { |
1326 |
if ((c = fn.apply(t)) == null) |
1327 |
ex = new NullPointerException(); |
1328 |
} catch (Throwable rex) { |
1329 |
ex = rex; |
1330 |
} |
1331 |
} |
1332 |
} |
1333 |
if (c != null) { |
1334 |
ThenCopy<U> d = null; |
1335 |
Object s; |
1336 |
if ((s = c.result) == null) { |
1337 |
CompletionNode p = new CompletionNode |
1338 |
(d = new ThenCopy<U>(c, dst)); |
1339 |
while ((s = c.result) == null) { |
1340 |
if (UNSAFE.compareAndSwapObject |
1341 |
(c, COMPLETIONS, p.next = c.completions, p)) |
1342 |
break; |
1343 |
} |
1344 |
} |
1345 |
if (s != null && (d == null || d.compareAndSet(0, 1))) { |
1346 |
complete = true; |
1347 |
if (s instanceof AltResult) { |
1348 |
ex = ((AltResult)s).ex; // no rewrap |
1349 |
u = null; |
1350 |
} |
1351 |
else { |
1352 |
@SuppressWarnings("unchecked") U us = (U) s; |
1353 |
u = us; |
1354 |
} |
1355 |
} |
1356 |
} |
1357 |
if (complete || ex != null) |
1358 |
dst.internalComplete(u, ex); |
1359 |
if (c != null) |
1360 |
c.helpPostComplete(); |
1361 |
} |
1362 |
} |
1363 |
private static final long serialVersionUID = 5232453952276885070L; |
1364 |
} |
1365 |
|
1366 |
// public methods |
1367 |
|
1368 |
/** |
1369 |
* Creates a new incomplete CompletableFuture. |
1370 |
*/ |
1371 |
public CompletableFuture() { |
1372 |
} |
1373 |
|
1374 |
/** |
1375 |
* Returns a new CompletableFuture that is asynchronously completed |
1376 |
* by a task running in the {@link ForkJoinPool#commonPool()} with |
1377 |
* the value obtained by calling the given Supplier. |
1378 |
* |
1379 |
* @param supplier a function returning the value to be used |
1380 |
* to complete the returned CompletableFuture |
1381 |
* @return the new CompletableFuture |
1382 |
*/ |
1383 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier) { |
1384 |
if (supplier == null) throw new NullPointerException(); |
1385 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
1386 |
ForkJoinPool.commonPool(). |
1387 |
execute((ForkJoinTask<?>)new AsyncSupply<U>(supplier, f)); |
1388 |
return f; |
1389 |
} |
1390 |
|
1391 |
/** |
1392 |
* Returns a new CompletableFuture that is asynchronously completed |
1393 |
* by a task running in the given executor with the value obtained |
1394 |
* by calling the given Supplier. |
1395 |
* |
1396 |
* @param supplier a function returning the value to be used |
1397 |
* to complete the returned CompletableFuture |
1398 |
* @param executor the executor to use for asynchronous execution |
1399 |
* @return the new CompletableFuture |
1400 |
*/ |
1401 |
public static <U> CompletableFuture<U> supplyAsync(Supplier<U> supplier, |
1402 |
Executor executor) { |
1403 |
if (executor == null || supplier == null) |
1404 |
throw new NullPointerException(); |
1405 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
1406 |
executor.execute(new AsyncSupply<U>(supplier, f)); |
1407 |
return f; |
1408 |
} |
1409 |
|
1410 |
/** |
1411 |
* Returns a new CompletableFuture that is asynchronously completed |
1412 |
* by a task running in the {@link ForkJoinPool#commonPool()} after |
1413 |
* it runs the given action. |
1414 |
* |
1415 |
* @param runnable the action to run before completing the |
1416 |
* returned CompletableFuture |
1417 |
* @return the new CompletableFuture |
1418 |
*/ |
1419 |
public static CompletableFuture<Void> runAsync(Runnable runnable) { |
1420 |
if (runnable == null) throw new NullPointerException(); |
1421 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
1422 |
ForkJoinPool.commonPool(). |
1423 |
execute((ForkJoinTask<?>)new AsyncRun(runnable, f)); |
1424 |
return f; |
1425 |
} |
1426 |
|
1427 |
/** |
1428 |
* Returns a new CompletableFuture that is asynchronously completed |
1429 |
* by a task running in the given executor after it runs the given |
1430 |
* action. |
1431 |
* |
1432 |
* @param runnable the action to run before completing the |
1433 |
* returned CompletableFuture |
1434 |
* @param executor the executor to use for asynchronous execution |
1435 |
* @return the new CompletableFuture |
1436 |
*/ |
1437 |
public static CompletableFuture<Void> runAsync(Runnable runnable, |
1438 |
Executor executor) { |
1439 |
if (executor == null || runnable == null) |
1440 |
throw new NullPointerException(); |
1441 |
CompletableFuture<Void> f = new CompletableFuture<Void>(); |
1442 |
executor.execute(new AsyncRun(runnable, f)); |
1443 |
return f; |
1444 |
} |
1445 |
|
1446 |
/** |
1447 |
* Returns a new CompletableFuture that is already completed with |
1448 |
* the given value. |
1449 |
* |
1450 |
* @param value the value |
1451 |
* @return the completed CompletableFuture |
1452 |
*/ |
1453 |
public static <U> CompletableFuture<U> completedFuture(U value) { |
1454 |
CompletableFuture<U> f = new CompletableFuture<U>(); |
1455 |
f.result = (value == null) ? NIL : value; |
1456 |
return f; |
1457 |
} |
1458 |
|
1459 |
/** |
1460 |
* Returns {@code true} if completed in any fashion: normally, |
1461 |
* exceptionally, or via cancellation. |
1462 |
* |
1463 |
* @return {@code true} if completed |
1464 |
*/ |
1465 |
public boolean isDone() { |
1466 |
return result != null; |
1467 |
} |
1468 |
|
1469 |
/** |
1470 |
* Waits if necessary for this future to complete, and then |
1471 |
* returns its result. |
1472 |
* |
1473 |
* @return the result value |
1474 |
* @throws CancellationException if this future was cancelled |
1475 |
* @throws ExecutionException if this future completed exceptionally |
1476 |
* @throws InterruptedException if the current thread was interrupted |
1477 |
* while waiting |
1478 |
*/ |
1479 |
public T get() throws InterruptedException, ExecutionException { |
1480 |
Object r; Throwable ex, cause; |
1481 |
if ((r = result) == null && (r = waitingGet(true)) == null) |
1482 |
throw new InterruptedException(); |
1483 |
if (!(r instanceof AltResult)) { |
1484 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1485 |
return tr; |
1486 |
} |
1487 |
if ((ex = ((AltResult)r).ex) == null) |
1488 |
return null; |
1489 |
if (ex instanceof CancellationException) |
1490 |
throw (CancellationException)ex; |
1491 |
if ((ex instanceof CompletionException) && |
1492 |
(cause = ex.getCause()) != null) |
1493 |
ex = cause; |
1494 |
throw new ExecutionException(ex); |
1495 |
} |
1496 |
|
1497 |
/** |
1498 |
* Waits if necessary for at most the given time for this future |
1499 |
* to complete, and then returns its result, if available. |
1500 |
* |
1501 |
* @param timeout the maximum time to wait |
1502 |
* @param unit the time unit of the timeout argument |
1503 |
* @return the result value |
1504 |
* @throws CancellationException if this future was cancelled |
1505 |
* @throws ExecutionException if this future completed exceptionally |
1506 |
* @throws InterruptedException if the current thread was interrupted |
1507 |
* while waiting |
1508 |
* @throws TimeoutException if the wait timed out |
1509 |
*/ |
1510 |
public T get(long timeout, TimeUnit unit) |
1511 |
throws InterruptedException, ExecutionException, TimeoutException { |
1512 |
Object r; Throwable ex, cause; |
1513 |
long nanos = unit.toNanos(timeout); |
1514 |
if (Thread.interrupted()) |
1515 |
throw new InterruptedException(); |
1516 |
if ((r = result) == null) |
1517 |
r = timedAwaitDone(nanos); |
1518 |
if (!(r instanceof AltResult)) { |
1519 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1520 |
return tr; |
1521 |
} |
1522 |
if ((ex = ((AltResult)r).ex) == null) |
1523 |
return null; |
1524 |
if (ex instanceof CancellationException) |
1525 |
throw (CancellationException)ex; |
1526 |
if ((ex instanceof CompletionException) && |
1527 |
(cause = ex.getCause()) != null) |
1528 |
ex = cause; |
1529 |
throw new ExecutionException(ex); |
1530 |
} |
1531 |
|
1532 |
/** |
1533 |
* Returns the result value when complete, or throws an |
1534 |
* (unchecked) exception if completed exceptionally. To better |
1535 |
* conform with the use of common functional forms, if a |
1536 |
* computation involved in the completion of this |
1537 |
* CompletableFuture threw an exception, this method throws an |
1538 |
* (unchecked) {@link CompletionException} with the underlying |
1539 |
* exception as its cause. |
1540 |
* |
1541 |
* @return the result value |
1542 |
* @throws CancellationException if the computation was cancelled |
1543 |
* @throws CompletionException if this future completed |
1544 |
* exceptionally or a completion computation threw an exception |
1545 |
*/ |
1546 |
public T join() { |
1547 |
Object r; Throwable ex; |
1548 |
if ((r = result) == null) |
1549 |
r = waitingGet(false); |
1550 |
if (!(r instanceof AltResult)) { |
1551 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1552 |
return tr; |
1553 |
} |
1554 |
if ((ex = ((AltResult)r).ex) == null) |
1555 |
return null; |
1556 |
if (ex instanceof CancellationException) |
1557 |
throw (CancellationException)ex; |
1558 |
if (ex instanceof CompletionException) |
1559 |
throw (CompletionException)ex; |
1560 |
throw new CompletionException(ex); |
1561 |
} |
1562 |
|
1563 |
/** |
1564 |
* Returns the result value (or throws any encountered exception) |
1565 |
* if completed, else returns the given valueIfAbsent. |
1566 |
* |
1567 |
* @param valueIfAbsent the value to return if not completed |
1568 |
* @return the result value, if completed, else the given valueIfAbsent |
1569 |
* @throws CancellationException if the computation was cancelled |
1570 |
* @throws CompletionException if this future completed |
1571 |
* exceptionally or a completion computation threw an exception |
1572 |
*/ |
1573 |
public T getNow(T valueIfAbsent) { |
1574 |
Object r; Throwable ex; |
1575 |
if ((r = result) == null) |
1576 |
return valueIfAbsent; |
1577 |
if (!(r instanceof AltResult)) { |
1578 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1579 |
return tr; |
1580 |
} |
1581 |
if ((ex = ((AltResult)r).ex) == null) |
1582 |
return null; |
1583 |
if (ex instanceof CancellationException) |
1584 |
throw (CancellationException)ex; |
1585 |
if (ex instanceof CompletionException) |
1586 |
throw (CompletionException)ex; |
1587 |
throw new CompletionException(ex); |
1588 |
} |
1589 |
|
1590 |
/** |
1591 |
* If not already completed, sets the value returned by {@link |
1592 |
* #get()} and related methods to the given value. |
1593 |
* |
1594 |
* @param value the result value |
1595 |
* @return {@code true} if this invocation caused this CompletableFuture |
1596 |
* to transition to a completed state, else {@code false} |
1597 |
*/ |
1598 |
public boolean complete(T value) { |
1599 |
boolean triggered = result == null && |
1600 |
UNSAFE.compareAndSwapObject(this, RESULT, null, |
1601 |
value == null ? NIL : value); |
1602 |
postComplete(); |
1603 |
return triggered; |
1604 |
} |
1605 |
|
1606 |
/** |
1607 |
* If not already completed, causes invocations of {@link #get()} |
1608 |
* and related methods to throw the given exception. |
1609 |
* |
1610 |
* @param ex the exception |
1611 |
* @return {@code true} if this invocation caused this CompletableFuture |
1612 |
* to transition to a completed state, else {@code false} |
1613 |
*/ |
1614 |
public boolean completeExceptionally(Throwable ex) { |
1615 |
if (ex == null) throw new NullPointerException(); |
1616 |
boolean triggered = result == null && |
1617 |
UNSAFE.compareAndSwapObject(this, RESULT, null, new AltResult(ex)); |
1618 |
postComplete(); |
1619 |
return triggered; |
1620 |
} |
1621 |
|
1622 |
/** |
1623 |
* Returns a new CompletableFuture that is completed |
1624 |
* when this CompletableFuture completes, with the result of the |
1625 |
* given function of this CompletableFuture's result. |
1626 |
* |
1627 |
* <p>If this CompletableFuture completes exceptionally, or the |
1628 |
* supplied function throws an exception, then the returned |
1629 |
* CompletableFuture completes exceptionally with a |
1630 |
* CompletionException holding the exception as its cause. |
1631 |
* |
1632 |
* @param fn the function to use to compute the value of |
1633 |
* the returned CompletableFuture |
1634 |
* @return the new CompletableFuture |
1635 |
*/ |
1636 |
public <U> CompletableFuture<U> thenApply(Function<? super T,? extends U> fn) { |
1637 |
return doThenApply(fn, null); |
1638 |
} |
1639 |
|
1640 |
/** |
1641 |
* Returns a new CompletableFuture that is asynchronously completed |
1642 |
* when this CompletableFuture completes, with the result of the |
1643 |
* given function of this CompletableFuture's result from a |
1644 |
* task running in the {@link ForkJoinPool#commonPool()}. |
1645 |
* |
1646 |
* <p>If this CompletableFuture completes exceptionally, or the |
1647 |
* supplied function throws an exception, then the returned |
1648 |
* CompletableFuture completes exceptionally with a |
1649 |
* CompletionException holding the exception as its cause. |
1650 |
* |
1651 |
* @param fn the function to use to compute the value of |
1652 |
* the returned CompletableFuture |
1653 |
* @return the new CompletableFuture |
1654 |
*/ |
1655 |
public <U> CompletableFuture<U> thenApplyAsync |
1656 |
(Function<? super T,? extends U> fn) { |
1657 |
return doThenApply(fn, ForkJoinPool.commonPool()); |
1658 |
} |
1659 |
|
1660 |
/** |
1661 |
* Returns a new CompletableFuture that is asynchronously completed |
1662 |
* when this CompletableFuture completes, with the result of the |
1663 |
* given function of this CompletableFuture's result from a |
1664 |
* task running in the given executor. |
1665 |
* |
1666 |
* <p>If this CompletableFuture completes exceptionally, or the |
1667 |
* supplied function throws an exception, then the returned |
1668 |
* CompletableFuture completes exceptionally with a |
1669 |
* CompletionException holding the exception as its cause. |
1670 |
* |
1671 |
* @param fn the function to use to compute the value of |
1672 |
* the returned CompletableFuture |
1673 |
* @param executor the executor to use for asynchronous execution |
1674 |
* @return the new CompletableFuture |
1675 |
*/ |
1676 |
public <U> CompletableFuture<U> thenApplyAsync |
1677 |
(Function<? super T,? extends U> fn, |
1678 |
Executor executor) { |
1679 |
if (executor == null) throw new NullPointerException(); |
1680 |
return doThenApply(fn, executor); |
1681 |
} |
1682 |
|
1683 |
private <U> CompletableFuture<U> doThenApply |
1684 |
(Function<? super T,? extends U> fn, |
1685 |
Executor e) { |
1686 |
if (fn == null) throw new NullPointerException(); |
1687 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
1688 |
ApplyCompletion<T,U> d = null; |
1689 |
Object r; |
1690 |
if ((r = result) == null) { |
1691 |
CompletionNode p = new CompletionNode |
1692 |
(d = new ApplyCompletion<T,U>(this, fn, dst, e)); |
1693 |
while ((r = result) == null) { |
1694 |
if (UNSAFE.compareAndSwapObject |
1695 |
(this, COMPLETIONS, p.next = completions, p)) |
1696 |
break; |
1697 |
} |
1698 |
} |
1699 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1700 |
T t; Throwable ex; |
1701 |
if (r instanceof AltResult) { |
1702 |
ex = ((AltResult)r).ex; |
1703 |
t = null; |
1704 |
} |
1705 |
else { |
1706 |
ex = null; |
1707 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1708 |
t = tr; |
1709 |
} |
1710 |
U u = null; |
1711 |
if (ex == null) { |
1712 |
try { |
1713 |
if (e != null) |
1714 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
1715 |
else |
1716 |
u = fn.apply(t); |
1717 |
} catch (Throwable rex) { |
1718 |
ex = rex; |
1719 |
} |
1720 |
} |
1721 |
if (e == null || ex != null) |
1722 |
dst.internalComplete(u, ex); |
1723 |
} |
1724 |
helpPostComplete(); |
1725 |
return dst; |
1726 |
} |
1727 |
|
1728 |
/** |
1729 |
* Returns a new CompletableFuture that is completed |
1730 |
* when this CompletableFuture completes, after performing the given |
1731 |
* action with this CompletableFuture's result. |
1732 |
* |
1733 |
* <p>If this CompletableFuture completes exceptionally, or the |
1734 |
* supplied action throws an exception, then the returned |
1735 |
* CompletableFuture completes exceptionally with a |
1736 |
* CompletionException holding the exception as its cause. |
1737 |
* |
1738 |
* @param block the action to perform before completing the |
1739 |
* returned CompletableFuture |
1740 |
* @return the new CompletableFuture |
1741 |
*/ |
1742 |
public CompletableFuture<Void> thenAccept(Consumer<? super T> block) { |
1743 |
return doThenAccept(block, null); |
1744 |
} |
1745 |
|
1746 |
/** |
1747 |
* Returns a new CompletableFuture that is asynchronously completed |
1748 |
* when this CompletableFuture completes, after performing the given |
1749 |
* action with this CompletableFuture's result from a task running |
1750 |
* in the {@link ForkJoinPool#commonPool()}. |
1751 |
* |
1752 |
* <p>If this CompletableFuture completes exceptionally, or the |
1753 |
* supplied action throws an exception, then the returned |
1754 |
* CompletableFuture completes exceptionally with a |
1755 |
* CompletionException holding the exception as its cause. |
1756 |
* |
1757 |
* @param block the action to perform before completing the |
1758 |
* returned CompletableFuture |
1759 |
* @return the new CompletableFuture |
1760 |
*/ |
1761 |
public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> block) { |
1762 |
return doThenAccept(block, ForkJoinPool.commonPool()); |
1763 |
} |
1764 |
|
1765 |
/** |
1766 |
* Returns a new CompletableFuture that is asynchronously completed |
1767 |
* when this CompletableFuture completes, after performing the given |
1768 |
* action with this CompletableFuture's result from a task running |
1769 |
* in the given executor. |
1770 |
* |
1771 |
* <p>If this CompletableFuture completes exceptionally, or the |
1772 |
* supplied action throws an exception, then the returned |
1773 |
* CompletableFuture completes exceptionally with a |
1774 |
* CompletionException holding the exception as its cause. |
1775 |
* |
1776 |
* @param block the action to perform before completing the |
1777 |
* returned CompletableFuture |
1778 |
* @param executor the executor to use for asynchronous execution |
1779 |
* @return the new CompletableFuture |
1780 |
*/ |
1781 |
public CompletableFuture<Void> thenAcceptAsync(Consumer<? super T> block, |
1782 |
Executor executor) { |
1783 |
if (executor == null) throw new NullPointerException(); |
1784 |
return doThenAccept(block, executor); |
1785 |
} |
1786 |
|
1787 |
private CompletableFuture<Void> doThenAccept(Consumer<? super T> fn, |
1788 |
Executor e) { |
1789 |
if (fn == null) throw new NullPointerException(); |
1790 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1791 |
AcceptCompletion<T> d = null; |
1792 |
Object r; |
1793 |
if ((r = result) == null) { |
1794 |
CompletionNode p = new CompletionNode |
1795 |
(d = new AcceptCompletion<T>(this, fn, dst, e)); |
1796 |
while ((r = result) == null) { |
1797 |
if (UNSAFE.compareAndSwapObject |
1798 |
(this, COMPLETIONS, p.next = completions, p)) |
1799 |
break; |
1800 |
} |
1801 |
} |
1802 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1803 |
T t; Throwable ex; |
1804 |
if (r instanceof AltResult) { |
1805 |
ex = ((AltResult)r).ex; |
1806 |
t = null; |
1807 |
} |
1808 |
else { |
1809 |
ex = null; |
1810 |
@SuppressWarnings("unchecked") T tr = (T) r; |
1811 |
t = tr; |
1812 |
} |
1813 |
if (ex == null) { |
1814 |
try { |
1815 |
if (e != null) |
1816 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
1817 |
else |
1818 |
fn.accept(t); |
1819 |
} catch (Throwable rex) { |
1820 |
ex = rex; |
1821 |
} |
1822 |
} |
1823 |
if (e == null || ex != null) |
1824 |
dst.internalComplete(null, ex); |
1825 |
} |
1826 |
helpPostComplete(); |
1827 |
return dst; |
1828 |
} |
1829 |
|
1830 |
/** |
1831 |
* Returns a new CompletableFuture that is completed |
1832 |
* when this CompletableFuture completes, after performing the given |
1833 |
* action. |
1834 |
* |
1835 |
* <p>If this CompletableFuture completes exceptionally, or the |
1836 |
* supplied action throws an exception, then the returned |
1837 |
* CompletableFuture completes exceptionally with a |
1838 |
* CompletionException holding the exception as its cause. |
1839 |
* |
1840 |
* @param action the action to perform before completing the |
1841 |
* returned CompletableFuture |
1842 |
* @return the new CompletableFuture |
1843 |
*/ |
1844 |
public CompletableFuture<Void> thenRun(Runnable action) { |
1845 |
return doThenRun(action, null); |
1846 |
} |
1847 |
|
1848 |
/** |
1849 |
* Returns a new CompletableFuture that is asynchronously completed |
1850 |
* when this CompletableFuture completes, after performing the given |
1851 |
* action from a task running in the {@link ForkJoinPool#commonPool()}. |
1852 |
* |
1853 |
* <p>If this CompletableFuture completes exceptionally, or the |
1854 |
* supplied action throws an exception, then the returned |
1855 |
* CompletableFuture completes exceptionally with a |
1856 |
* CompletionException holding the exception as its cause. |
1857 |
* |
1858 |
* @param action the action to perform before completing the |
1859 |
* returned CompletableFuture |
1860 |
* @return the new CompletableFuture |
1861 |
*/ |
1862 |
public CompletableFuture<Void> thenRunAsync(Runnable action) { |
1863 |
return doThenRun(action, ForkJoinPool.commonPool()); |
1864 |
} |
1865 |
|
1866 |
/** |
1867 |
* Returns a new CompletableFuture that is asynchronously completed |
1868 |
* when this CompletableFuture completes, after performing the given |
1869 |
* action from a task running in the given executor. |
1870 |
* |
1871 |
* <p>If this CompletableFuture completes exceptionally, or the |
1872 |
* supplied action throws an exception, then the returned |
1873 |
* CompletableFuture completes exceptionally with a |
1874 |
* CompletionException holding the exception as its cause. |
1875 |
* |
1876 |
* @param action the action to perform before completing the |
1877 |
* returned CompletableFuture |
1878 |
* @param executor the executor to use for asynchronous execution |
1879 |
* @return the new CompletableFuture |
1880 |
*/ |
1881 |
public CompletableFuture<Void> thenRunAsync(Runnable action, |
1882 |
Executor executor) { |
1883 |
if (executor == null) throw new NullPointerException(); |
1884 |
return doThenRun(action, executor); |
1885 |
} |
1886 |
|
1887 |
private CompletableFuture<Void> doThenRun(Runnable action, |
1888 |
Executor e) { |
1889 |
if (action == null) throw new NullPointerException(); |
1890 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
1891 |
RunCompletion<T> d = null; |
1892 |
Object r; |
1893 |
if ((r = result) == null) { |
1894 |
CompletionNode p = new CompletionNode |
1895 |
(d = new RunCompletion<T>(this, action, dst, e)); |
1896 |
while ((r = result) == null) { |
1897 |
if (UNSAFE.compareAndSwapObject |
1898 |
(this, COMPLETIONS, p.next = completions, p)) |
1899 |
break; |
1900 |
} |
1901 |
} |
1902 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
1903 |
Throwable ex; |
1904 |
if (r instanceof AltResult) |
1905 |
ex = ((AltResult)r).ex; |
1906 |
else |
1907 |
ex = null; |
1908 |
if (ex == null) { |
1909 |
try { |
1910 |
if (e != null) |
1911 |
e.execute(new AsyncRun(action, dst)); |
1912 |
else |
1913 |
action.run(); |
1914 |
} catch (Throwable rex) { |
1915 |
ex = rex; |
1916 |
} |
1917 |
} |
1918 |
if (e == null || ex != null) |
1919 |
dst.internalComplete(null, ex); |
1920 |
} |
1921 |
helpPostComplete(); |
1922 |
return dst; |
1923 |
} |
1924 |
|
1925 |
/** |
1926 |
* Returns a new CompletableFuture that is completed |
1927 |
* when both this and the other given CompletableFuture complete, |
1928 |
* with the result of the given function of the results of the two |
1929 |
* CompletableFutures. |
1930 |
* |
1931 |
* <p>If this and/or the other CompletableFuture complete |
1932 |
* exceptionally, or the supplied function throws an exception, |
1933 |
* then the returned CompletableFuture completes exceptionally |
1934 |
* with a CompletionException holding the exception as its cause. |
1935 |
* |
1936 |
* @param other the other CompletableFuture |
1937 |
* @param fn the function to use to compute the value of |
1938 |
* the returned CompletableFuture |
1939 |
* @return the new CompletableFuture |
1940 |
*/ |
1941 |
public <U,V> CompletableFuture<V> thenCombine |
1942 |
(CompletableFuture<? extends U> other, |
1943 |
BiFunction<? super T,? super U,? extends V> fn) { |
1944 |
return doThenBiApply(other, fn, null); |
1945 |
} |
1946 |
|
1947 |
/** |
1948 |
* Returns a new CompletableFuture that is asynchronously completed |
1949 |
* when both this and the other given CompletableFuture complete, |
1950 |
* with the result of the given function of the results of the two |
1951 |
* CompletableFutures from a task running in the |
1952 |
* {@link ForkJoinPool#commonPool()}. |
1953 |
* |
1954 |
* <p>If this and/or the other CompletableFuture complete |
1955 |
* exceptionally, or the supplied function throws an exception, |
1956 |
* then the returned CompletableFuture completes exceptionally |
1957 |
* with a CompletionException holding the exception as its cause. |
1958 |
* |
1959 |
* @param other the other CompletableFuture |
1960 |
* @param fn the function to use to compute the value of |
1961 |
* the returned CompletableFuture |
1962 |
* @return the new CompletableFuture |
1963 |
*/ |
1964 |
public <U,V> CompletableFuture<V> thenCombineAsync |
1965 |
(CompletableFuture<? extends U> other, |
1966 |
BiFunction<? super T,? super U,? extends V> fn) { |
1967 |
return doThenBiApply(other, fn, ForkJoinPool.commonPool()); |
1968 |
} |
1969 |
|
1970 |
/** |
1971 |
* Returns a new CompletableFuture that is asynchronously completed |
1972 |
* when both this and the other given CompletableFuture complete, |
1973 |
* with the result of the given function of the results of the two |
1974 |
* CompletableFutures from a task running in the given executor. |
1975 |
* |
1976 |
* <p>If this and/or the other CompletableFuture complete |
1977 |
* exceptionally, or the supplied function throws an exception, |
1978 |
* then the returned CompletableFuture completes exceptionally |
1979 |
* with a CompletionException holding the exception as its cause. |
1980 |
* |
1981 |
* @param other the other CompletableFuture |
1982 |
* @param fn the function to use to compute the value of |
1983 |
* the returned CompletableFuture |
1984 |
* @param executor the executor to use for asynchronous execution |
1985 |
* @return the new CompletableFuture |
1986 |
*/ |
1987 |
public <U,V> CompletableFuture<V> thenCombineAsync |
1988 |
(CompletableFuture<? extends U> other, |
1989 |
BiFunction<? super T,? super U,? extends V> fn, |
1990 |
Executor executor) { |
1991 |
if (executor == null) throw new NullPointerException(); |
1992 |
return doThenBiApply(other, fn, executor); |
1993 |
} |
1994 |
|
1995 |
private <U,V> CompletableFuture<V> doThenBiApply |
1996 |
(CompletableFuture<? extends U> other, |
1997 |
BiFunction<? super T,? super U,? extends V> fn, |
1998 |
Executor e) { |
1999 |
if (other == null || fn == null) throw new NullPointerException(); |
2000 |
CompletableFuture<V> dst = new CompletableFuture<V>(); |
2001 |
BiApplyCompletion<T,U,V> d = null; |
2002 |
Object r, s = null; |
2003 |
if ((r = result) == null || (s = other.result) == null) { |
2004 |
d = new BiApplyCompletion<T,U,V>(this, other, fn, dst, e); |
2005 |
CompletionNode q = null, p = new CompletionNode(d); |
2006 |
while ((r == null && (r = result) == null) || |
2007 |
(s == null && (s = other.result) == null)) { |
2008 |
if (q != null) { |
2009 |
if (s != null || |
2010 |
UNSAFE.compareAndSwapObject |
2011 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2012 |
break; |
2013 |
} |
2014 |
else if (r != null || |
2015 |
UNSAFE.compareAndSwapObject |
2016 |
(this, COMPLETIONS, p.next = completions, p)) { |
2017 |
if (s != null) |
2018 |
break; |
2019 |
q = new CompletionNode(d); |
2020 |
} |
2021 |
} |
2022 |
} |
2023 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
2024 |
T t; U u; Throwable ex; |
2025 |
if (r instanceof AltResult) { |
2026 |
ex = ((AltResult)r).ex; |
2027 |
t = null; |
2028 |
} |
2029 |
else { |
2030 |
ex = null; |
2031 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2032 |
t = tr; |
2033 |
} |
2034 |
if (ex != null) |
2035 |
u = null; |
2036 |
else if (s instanceof AltResult) { |
2037 |
ex = ((AltResult)s).ex; |
2038 |
u = null; |
2039 |
} |
2040 |
else { |
2041 |
@SuppressWarnings("unchecked") U us = (U) s; |
2042 |
u = us; |
2043 |
} |
2044 |
V v = null; |
2045 |
if (ex == null) { |
2046 |
try { |
2047 |
if (e != null) |
2048 |
e.execute(new AsyncBiApply<T,U,V>(t, u, fn, dst)); |
2049 |
else |
2050 |
v = fn.apply(t, u); |
2051 |
} catch (Throwable rex) { |
2052 |
ex = rex; |
2053 |
} |
2054 |
} |
2055 |
if (e == null || ex != null) |
2056 |
dst.internalComplete(v, ex); |
2057 |
} |
2058 |
helpPostComplete(); |
2059 |
other.helpPostComplete(); |
2060 |
return dst; |
2061 |
} |
2062 |
|
2063 |
/** |
2064 |
* Returns a new CompletableFuture that is completed |
2065 |
* when both this and the other given CompletableFuture complete, |
2066 |
* after performing the given action with the results of the two |
2067 |
* CompletableFutures. |
2068 |
* |
2069 |
* <p>If this and/or the other CompletableFuture complete |
2070 |
* exceptionally, or the supplied action throws an exception, |
2071 |
* then the returned CompletableFuture completes exceptionally |
2072 |
* with a CompletionException holding the exception as its cause. |
2073 |
* |
2074 |
* @param other the other CompletableFuture |
2075 |
* @param block the action to perform before completing the |
2076 |
* returned CompletableFuture |
2077 |
* @return the new CompletableFuture |
2078 |
*/ |
2079 |
public <U> CompletableFuture<Void> thenAcceptBoth |
2080 |
(CompletableFuture<? extends U> other, |
2081 |
BiConsumer<? super T, ? super U> block) { |
2082 |
return doThenBiAccept(other, block, null); |
2083 |
} |
2084 |
|
2085 |
/** |
2086 |
* Returns a new CompletableFuture that is asynchronously completed |
2087 |
* when both this and the other given CompletableFuture complete, |
2088 |
* after performing the given action with the results of the two |
2089 |
* CompletableFutures from a task running in the {@link |
2090 |
* ForkJoinPool#commonPool()}. |
2091 |
* |
2092 |
* <p>If this and/or the other CompletableFuture complete |
2093 |
* exceptionally, or the supplied action throws an exception, |
2094 |
* then the returned CompletableFuture completes exceptionally |
2095 |
* with a CompletionException holding the exception as its cause. |
2096 |
* |
2097 |
* @param other the other CompletableFuture |
2098 |
* @param block the action to perform before completing the |
2099 |
* returned CompletableFuture |
2100 |
* @return the new CompletableFuture |
2101 |
*/ |
2102 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2103 |
(CompletableFuture<? extends U> other, |
2104 |
BiConsumer<? super T, ? super U> block) { |
2105 |
return doThenBiAccept(other, block, ForkJoinPool.commonPool()); |
2106 |
} |
2107 |
|
2108 |
/** |
2109 |
* Returns a new CompletableFuture that is asynchronously completed |
2110 |
* when both this and the other given CompletableFuture complete, |
2111 |
* after performing the given action with the results of the two |
2112 |
* CompletableFutures from a task running in the given executor. |
2113 |
* |
2114 |
* <p>If this and/or the other CompletableFuture complete |
2115 |
* exceptionally, or the supplied action throws an exception, |
2116 |
* then the returned CompletableFuture completes exceptionally |
2117 |
* with a CompletionException holding the exception as its cause. |
2118 |
* |
2119 |
* @param other the other CompletableFuture |
2120 |
* @param block the action to perform before completing the |
2121 |
* returned CompletableFuture |
2122 |
* @param executor the executor to use for asynchronous execution |
2123 |
* @return the new CompletableFuture |
2124 |
*/ |
2125 |
public <U> CompletableFuture<Void> thenAcceptBothAsync |
2126 |
(CompletableFuture<? extends U> other, |
2127 |
BiConsumer<? super T, ? super U> block, |
2128 |
Executor executor) { |
2129 |
if (executor == null) throw new NullPointerException(); |
2130 |
return doThenBiAccept(other, block, executor); |
2131 |
} |
2132 |
|
2133 |
private <U> CompletableFuture<Void> doThenBiAccept |
2134 |
(CompletableFuture<? extends U> other, |
2135 |
BiConsumer<? super T,? super U> fn, |
2136 |
Executor e) { |
2137 |
if (other == null || fn == null) throw new NullPointerException(); |
2138 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2139 |
BiAcceptCompletion<T,U> d = null; |
2140 |
Object r, s = null; |
2141 |
if ((r = result) == null || (s = other.result) == null) { |
2142 |
d = new BiAcceptCompletion<T,U>(this, other, fn, dst, e); |
2143 |
CompletionNode q = null, p = new CompletionNode(d); |
2144 |
while ((r == null && (r = result) == null) || |
2145 |
(s == null && (s = other.result) == null)) { |
2146 |
if (q != null) { |
2147 |
if (s != null || |
2148 |
UNSAFE.compareAndSwapObject |
2149 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2150 |
break; |
2151 |
} |
2152 |
else if (r != null || |
2153 |
UNSAFE.compareAndSwapObject |
2154 |
(this, COMPLETIONS, p.next = completions, p)) { |
2155 |
if (s != null) |
2156 |
break; |
2157 |
q = new CompletionNode(d); |
2158 |
} |
2159 |
} |
2160 |
} |
2161 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
2162 |
T t; U u; Throwable ex; |
2163 |
if (r instanceof AltResult) { |
2164 |
ex = ((AltResult)r).ex; |
2165 |
t = null; |
2166 |
} |
2167 |
else { |
2168 |
ex = null; |
2169 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2170 |
t = tr; |
2171 |
} |
2172 |
if (ex != null) |
2173 |
u = null; |
2174 |
else if (s instanceof AltResult) { |
2175 |
ex = ((AltResult)s).ex; |
2176 |
u = null; |
2177 |
} |
2178 |
else { |
2179 |
@SuppressWarnings("unchecked") U us = (U) s; |
2180 |
u = us; |
2181 |
} |
2182 |
if (ex == null) { |
2183 |
try { |
2184 |
if (e != null) |
2185 |
e.execute(new AsyncBiAccept<T,U>(t, u, fn, dst)); |
2186 |
else |
2187 |
fn.accept(t, u); |
2188 |
} catch (Throwable rex) { |
2189 |
ex = rex; |
2190 |
} |
2191 |
} |
2192 |
if (e == null || ex != null) |
2193 |
dst.internalComplete(null, ex); |
2194 |
} |
2195 |
helpPostComplete(); |
2196 |
other.helpPostComplete(); |
2197 |
return dst; |
2198 |
} |
2199 |
|
2200 |
/** |
2201 |
* Returns a new CompletableFuture that is completed |
2202 |
* when both this and the other given CompletableFuture complete, |
2203 |
* after performing the given action. |
2204 |
* |
2205 |
* <p>If this and/or the other CompletableFuture complete |
2206 |
* exceptionally, or the supplied action throws an exception, |
2207 |
* then the returned CompletableFuture completes exceptionally |
2208 |
* with a CompletionException holding the exception as its cause. |
2209 |
* |
2210 |
* @param other the other CompletableFuture |
2211 |
* @param action the action to perform before completing the |
2212 |
* returned CompletableFuture |
2213 |
* @return the new CompletableFuture |
2214 |
*/ |
2215 |
public CompletableFuture<Void> runAfterBoth(CompletableFuture<?> other, |
2216 |
Runnable action) { |
2217 |
return doThenBiRun(other, action, null); |
2218 |
} |
2219 |
|
2220 |
/** |
2221 |
* Returns a new CompletableFuture that is asynchronously completed |
2222 |
* when both this and the other given CompletableFuture complete, |
2223 |
* after performing the given action from a task running in the |
2224 |
* {@link ForkJoinPool#commonPool()}. |
2225 |
* |
2226 |
* <p>If this and/or the other CompletableFuture complete |
2227 |
* exceptionally, or the supplied action throws an exception, |
2228 |
* then the returned CompletableFuture completes exceptionally |
2229 |
* with a CompletionException holding the exception as its cause. |
2230 |
* |
2231 |
* @param other the other CompletableFuture |
2232 |
* @param action the action to perform before completing the |
2233 |
* returned CompletableFuture |
2234 |
* @return the new CompletableFuture |
2235 |
*/ |
2236 |
public CompletableFuture<Void> runAfterBothAsync(CompletableFuture<?> other, |
2237 |
Runnable action) { |
2238 |
return doThenBiRun(other, action, ForkJoinPool.commonPool()); |
2239 |
} |
2240 |
|
2241 |
/** |
2242 |
* Returns a new CompletableFuture that is asynchronously completed |
2243 |
* when both this and the other given CompletableFuture complete, |
2244 |
* after performing the given action from a task running in the |
2245 |
* given executor. |
2246 |
* |
2247 |
* <p>If this and/or the other CompletableFuture complete |
2248 |
* exceptionally, or the supplied action throws an exception, |
2249 |
* then the returned CompletableFuture completes exceptionally |
2250 |
* with a CompletionException holding the exception as its cause. |
2251 |
* |
2252 |
* @param other the other CompletableFuture |
2253 |
* @param action the action to perform before completing the |
2254 |
* returned CompletableFuture |
2255 |
* @param executor the executor to use for asynchronous execution |
2256 |
* @return the new CompletableFuture |
2257 |
*/ |
2258 |
public CompletableFuture<Void> runAfterBothAsync(CompletableFuture<?> other, |
2259 |
Runnable action, |
2260 |
Executor executor) { |
2261 |
if (executor == null) throw new NullPointerException(); |
2262 |
return doThenBiRun(other, action, executor); |
2263 |
} |
2264 |
|
2265 |
private CompletableFuture<Void> doThenBiRun(CompletableFuture<?> other, |
2266 |
Runnable action, |
2267 |
Executor e) { |
2268 |
if (other == null || action == null) throw new NullPointerException(); |
2269 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2270 |
BiRunCompletion<T> d = null; |
2271 |
Object r, s = null; |
2272 |
if ((r = result) == null || (s = other.result) == null) { |
2273 |
d = new BiRunCompletion<T>(this, other, action, dst, e); |
2274 |
CompletionNode q = null, p = new CompletionNode(d); |
2275 |
while ((r == null && (r = result) == null) || |
2276 |
(s == null && (s = other.result) == null)) { |
2277 |
if (q != null) { |
2278 |
if (s != null || |
2279 |
UNSAFE.compareAndSwapObject |
2280 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2281 |
break; |
2282 |
} |
2283 |
else if (r != null || |
2284 |
UNSAFE.compareAndSwapObject |
2285 |
(this, COMPLETIONS, p.next = completions, p)) { |
2286 |
if (s != null) |
2287 |
break; |
2288 |
q = new CompletionNode(d); |
2289 |
} |
2290 |
} |
2291 |
} |
2292 |
if (r != null && s != null && (d == null || d.compareAndSet(0, 1))) { |
2293 |
Throwable ex; |
2294 |
if (r instanceof AltResult) |
2295 |
ex = ((AltResult)r).ex; |
2296 |
else |
2297 |
ex = null; |
2298 |
if (ex == null && (s instanceof AltResult)) |
2299 |
ex = ((AltResult)s).ex; |
2300 |
if (ex == null) { |
2301 |
try { |
2302 |
if (e != null) |
2303 |
e.execute(new AsyncRun(action, dst)); |
2304 |
else |
2305 |
action.run(); |
2306 |
} catch (Throwable rex) { |
2307 |
ex = rex; |
2308 |
} |
2309 |
} |
2310 |
if (e == null || ex != null) |
2311 |
dst.internalComplete(null, ex); |
2312 |
} |
2313 |
helpPostComplete(); |
2314 |
other.helpPostComplete(); |
2315 |
return dst; |
2316 |
} |
2317 |
|
2318 |
/** |
2319 |
* Returns a new CompletableFuture that is completed |
2320 |
* when either this or the other given CompletableFuture completes, |
2321 |
* with the result of the given function of either this or the other |
2322 |
* CompletableFuture's result. |
2323 |
* |
2324 |
* <p>If this and/or the other CompletableFuture complete |
2325 |
* exceptionally, then the returned CompletableFuture may also do so, |
2326 |
* with a CompletionException holding one of these exceptions as its |
2327 |
* cause. No guarantees are made about which result or exception is |
2328 |
* used in the returned CompletableFuture. If the supplied function |
2329 |
* throws an exception, then the returned CompletableFuture completes |
2330 |
* exceptionally with a CompletionException holding the exception as |
2331 |
* its cause. |
2332 |
* |
2333 |
* @param other the other CompletableFuture |
2334 |
* @param fn the function to use to compute the value of |
2335 |
* the returned CompletableFuture |
2336 |
* @return the new CompletableFuture |
2337 |
*/ |
2338 |
public <U> CompletableFuture<U> applyToEither |
2339 |
(CompletableFuture<? extends T> other, |
2340 |
Function<? super T, U> fn) { |
2341 |
return doOrApply(other, fn, null); |
2342 |
} |
2343 |
|
2344 |
/** |
2345 |
* Returns a new CompletableFuture that is asynchronously completed |
2346 |
* when either this or the other given CompletableFuture completes, |
2347 |
* with the result of the given function of either this or the other |
2348 |
* CompletableFuture's result from a task running in the |
2349 |
* {@link ForkJoinPool#commonPool()}. |
2350 |
* |
2351 |
* <p>If this and/or the other CompletableFuture complete |
2352 |
* exceptionally, then the returned CompletableFuture may also do so, |
2353 |
* with a CompletionException holding one of these exceptions as its |
2354 |
* cause. No guarantees are made about which result or exception is |
2355 |
* used in the returned CompletableFuture. If the supplied function |
2356 |
* throws an exception, then the returned CompletableFuture completes |
2357 |
* exceptionally with a CompletionException holding the exception as |
2358 |
* its cause. |
2359 |
* |
2360 |
* @param other the other CompletableFuture |
2361 |
* @param fn the function to use to compute the value of |
2362 |
* the returned CompletableFuture |
2363 |
* @return the new CompletableFuture |
2364 |
*/ |
2365 |
public <U> CompletableFuture<U> applyToEitherAsync |
2366 |
(CompletableFuture<? extends T> other, |
2367 |
Function<? super T, U> fn) { |
2368 |
return doOrApply(other, fn, ForkJoinPool.commonPool()); |
2369 |
} |
2370 |
|
2371 |
/** |
2372 |
* Returns a new CompletableFuture that is asynchronously completed |
2373 |
* when either this or the other given CompletableFuture completes, |
2374 |
* with the result of the given function of either this or the other |
2375 |
* CompletableFuture's result from a task running in the |
2376 |
* given executor. |
2377 |
* |
2378 |
* <p>If this and/or the other CompletableFuture complete |
2379 |
* exceptionally, then the returned CompletableFuture may also do so, |
2380 |
* with a CompletionException holding one of these exceptions as its |
2381 |
* cause. No guarantees are made about which result or exception is |
2382 |
* used in the returned CompletableFuture. If the supplied function |
2383 |
* throws an exception, then the returned CompletableFuture completes |
2384 |
* exceptionally with a CompletionException holding the exception as |
2385 |
* its cause. |
2386 |
* |
2387 |
* @param other the other CompletableFuture |
2388 |
* @param fn the function to use to compute the value of |
2389 |
* the returned CompletableFuture |
2390 |
* @param executor the executor to use for asynchronous execution |
2391 |
* @return the new CompletableFuture |
2392 |
*/ |
2393 |
public <U> CompletableFuture<U> applyToEitherAsync |
2394 |
(CompletableFuture<? extends T> other, |
2395 |
Function<? super T, U> fn, |
2396 |
Executor executor) { |
2397 |
if (executor == null) throw new NullPointerException(); |
2398 |
return doOrApply(other, fn, executor); |
2399 |
} |
2400 |
|
2401 |
private <U> CompletableFuture<U> doOrApply |
2402 |
(CompletableFuture<? extends T> other, |
2403 |
Function<? super T, U> fn, |
2404 |
Executor e) { |
2405 |
if (other == null || fn == null) throw new NullPointerException(); |
2406 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2407 |
OrApplyCompletion<T,U> d = null; |
2408 |
Object r; |
2409 |
if ((r = result) == null && (r = other.result) == null) { |
2410 |
d = new OrApplyCompletion<T,U>(this, other, fn, dst, e); |
2411 |
CompletionNode q = null, p = new CompletionNode(d); |
2412 |
while ((r = result) == null && (r = other.result) == null) { |
2413 |
if (q != null) { |
2414 |
if (UNSAFE.compareAndSwapObject |
2415 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2416 |
break; |
2417 |
} |
2418 |
else if (UNSAFE.compareAndSwapObject |
2419 |
(this, COMPLETIONS, p.next = completions, p)) |
2420 |
q = new CompletionNode(d); |
2421 |
} |
2422 |
} |
2423 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2424 |
T t; Throwable ex; |
2425 |
if (r instanceof AltResult) { |
2426 |
ex = ((AltResult)r).ex; |
2427 |
t = null; |
2428 |
} |
2429 |
else { |
2430 |
ex = null; |
2431 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2432 |
t = tr; |
2433 |
} |
2434 |
U u = null; |
2435 |
if (ex == null) { |
2436 |
try { |
2437 |
if (e != null) |
2438 |
e.execute(new AsyncApply<T,U>(t, fn, dst)); |
2439 |
else |
2440 |
u = fn.apply(t); |
2441 |
} catch (Throwable rex) { |
2442 |
ex = rex; |
2443 |
} |
2444 |
} |
2445 |
if (e == null || ex != null) |
2446 |
dst.internalComplete(u, ex); |
2447 |
} |
2448 |
helpPostComplete(); |
2449 |
other.helpPostComplete(); |
2450 |
return dst; |
2451 |
} |
2452 |
|
2453 |
/** |
2454 |
* Returns a new CompletableFuture that is completed |
2455 |
* when either this or the other given CompletableFuture completes, |
2456 |
* after performing the given action with the result of either this |
2457 |
* or the other CompletableFuture's result. |
2458 |
* |
2459 |
* <p>If this and/or the other CompletableFuture complete |
2460 |
* exceptionally, then the returned CompletableFuture may also do so, |
2461 |
* with a CompletionException holding one of these exceptions as its |
2462 |
* cause. No guarantees are made about which result or exception is |
2463 |
* used in the returned CompletableFuture. If the supplied action |
2464 |
* throws an exception, then the returned CompletableFuture completes |
2465 |
* exceptionally with a CompletionException holding the exception as |
2466 |
* its cause. |
2467 |
* |
2468 |
* @param other the other CompletableFuture |
2469 |
* @param block the action to perform before completing the |
2470 |
* returned CompletableFuture |
2471 |
* @return the new CompletableFuture |
2472 |
*/ |
2473 |
public CompletableFuture<Void> acceptEither |
2474 |
(CompletableFuture<? extends T> other, |
2475 |
Consumer<? super T> block) { |
2476 |
return doOrAccept(other, block, null); |
2477 |
} |
2478 |
|
2479 |
/** |
2480 |
* Returns a new CompletableFuture that is asynchronously completed |
2481 |
* when either this or the other given CompletableFuture completes, |
2482 |
* after performing the given action with the result of either this |
2483 |
* or the other CompletableFuture's result from a task running in |
2484 |
* the {@link ForkJoinPool#commonPool()}. |
2485 |
* |
2486 |
* <p>If this and/or the other CompletableFuture complete |
2487 |
* exceptionally, then the returned CompletableFuture may also do so, |
2488 |
* with a CompletionException holding one of these exceptions as its |
2489 |
* cause. No guarantees are made about which result or exception is |
2490 |
* used in the returned CompletableFuture. If the supplied action |
2491 |
* throws an exception, then the returned CompletableFuture completes |
2492 |
* exceptionally with a CompletionException holding the exception as |
2493 |
* its cause. |
2494 |
* |
2495 |
* @param other the other CompletableFuture |
2496 |
* @param block the action to perform before completing the |
2497 |
* returned CompletableFuture |
2498 |
* @return the new CompletableFuture |
2499 |
*/ |
2500 |
public CompletableFuture<Void> acceptEitherAsync |
2501 |
(CompletableFuture<? extends T> other, |
2502 |
Consumer<? super T> block) { |
2503 |
return doOrAccept(other, block, ForkJoinPool.commonPool()); |
2504 |
} |
2505 |
|
2506 |
/** |
2507 |
* Returns a new CompletableFuture that is asynchronously completed |
2508 |
* when either this or the other given CompletableFuture completes, |
2509 |
* after performing the given action with the result of either this |
2510 |
* or the other CompletableFuture's result from a task running in |
2511 |
* the given executor. |
2512 |
* |
2513 |
* <p>If this and/or the other CompletableFuture complete |
2514 |
* exceptionally, then the returned CompletableFuture may also do so, |
2515 |
* with a CompletionException holding one of these exceptions as its |
2516 |
* cause. No guarantees are made about which result or exception is |
2517 |
* used in the returned CompletableFuture. If the supplied action |
2518 |
* throws an exception, then the returned CompletableFuture completes |
2519 |
* exceptionally with a CompletionException holding the exception as |
2520 |
* its cause. |
2521 |
* |
2522 |
* @param other the other CompletableFuture |
2523 |
* @param block the action to perform before completing the |
2524 |
* returned CompletableFuture |
2525 |
* @param executor the executor to use for asynchronous execution |
2526 |
* @return the new CompletableFuture |
2527 |
*/ |
2528 |
public CompletableFuture<Void> acceptEitherAsync |
2529 |
(CompletableFuture<? extends T> other, |
2530 |
Consumer<? super T> block, |
2531 |
Executor executor) { |
2532 |
if (executor == null) throw new NullPointerException(); |
2533 |
return doOrAccept(other, block, executor); |
2534 |
} |
2535 |
|
2536 |
private CompletableFuture<Void> doOrAccept |
2537 |
(CompletableFuture<? extends T> other, |
2538 |
Consumer<? super T> fn, |
2539 |
Executor e) { |
2540 |
if (other == null || fn == null) throw new NullPointerException(); |
2541 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2542 |
OrAcceptCompletion<T> d = null; |
2543 |
Object r; |
2544 |
if ((r = result) == null && (r = other.result) == null) { |
2545 |
d = new OrAcceptCompletion<T>(this, other, fn, dst, e); |
2546 |
CompletionNode q = null, p = new CompletionNode(d); |
2547 |
while ((r = result) == null && (r = other.result) == null) { |
2548 |
if (q != null) { |
2549 |
if (UNSAFE.compareAndSwapObject |
2550 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2551 |
break; |
2552 |
} |
2553 |
else if (UNSAFE.compareAndSwapObject |
2554 |
(this, COMPLETIONS, p.next = completions, p)) |
2555 |
q = new CompletionNode(d); |
2556 |
} |
2557 |
} |
2558 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2559 |
T t; Throwable ex; |
2560 |
if (r instanceof AltResult) { |
2561 |
ex = ((AltResult)r).ex; |
2562 |
t = null; |
2563 |
} |
2564 |
else { |
2565 |
ex = null; |
2566 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2567 |
t = tr; |
2568 |
} |
2569 |
if (ex == null) { |
2570 |
try { |
2571 |
if (e != null) |
2572 |
e.execute(new AsyncAccept<T>(t, fn, dst)); |
2573 |
else |
2574 |
fn.accept(t); |
2575 |
} catch (Throwable rex) { |
2576 |
ex = rex; |
2577 |
} |
2578 |
} |
2579 |
if (e == null || ex != null) |
2580 |
dst.internalComplete(null, ex); |
2581 |
} |
2582 |
helpPostComplete(); |
2583 |
other.helpPostComplete(); |
2584 |
return dst; |
2585 |
} |
2586 |
|
2587 |
/** |
2588 |
* Returns a new CompletableFuture that is completed |
2589 |
* when either this or the other given CompletableFuture completes, |
2590 |
* after performing the given action. |
2591 |
* |
2592 |
* <p>If this and/or the other CompletableFuture complete |
2593 |
* exceptionally, then the returned CompletableFuture may also do so, |
2594 |
* with a CompletionException holding one of these exceptions as its |
2595 |
* cause. No guarantees are made about which result or exception is |
2596 |
* used in the returned CompletableFuture. If the supplied action |
2597 |
* throws an exception, then the returned CompletableFuture completes |
2598 |
* exceptionally with a CompletionException holding the exception as |
2599 |
* its cause. |
2600 |
* |
2601 |
* @param other the other CompletableFuture |
2602 |
* @param action the action to perform before completing the |
2603 |
* returned CompletableFuture |
2604 |
* @return the new CompletableFuture |
2605 |
*/ |
2606 |
public CompletableFuture<Void> runAfterEither(CompletableFuture<?> other, |
2607 |
Runnable action) { |
2608 |
return doOrRun(other, action, null); |
2609 |
} |
2610 |
|
2611 |
/** |
2612 |
* Returns a new CompletableFuture that is asynchronously completed |
2613 |
* when either this or the other given CompletableFuture completes, |
2614 |
* after performing the given action from a task running in the |
2615 |
* {@link ForkJoinPool#commonPool()}. |
2616 |
* |
2617 |
* <p>If this and/or the other CompletableFuture complete |
2618 |
* exceptionally, then the returned CompletableFuture may also do so, |
2619 |
* with a CompletionException holding one of these exceptions as its |
2620 |
* cause. No guarantees are made about which result or exception is |
2621 |
* used in the returned CompletableFuture. If the supplied action |
2622 |
* throws an exception, then the returned CompletableFuture completes |
2623 |
* exceptionally with a CompletionException holding the exception as |
2624 |
* its cause. |
2625 |
* |
2626 |
* @param other the other CompletableFuture |
2627 |
* @param action the action to perform before completing the |
2628 |
* returned CompletableFuture |
2629 |
* @return the new CompletableFuture |
2630 |
*/ |
2631 |
public CompletableFuture<Void> runAfterEitherAsync |
2632 |
(CompletableFuture<?> other, |
2633 |
Runnable action) { |
2634 |
return doOrRun(other, action, ForkJoinPool.commonPool()); |
2635 |
} |
2636 |
|
2637 |
/** |
2638 |
* Returns a new CompletableFuture that is asynchronously completed |
2639 |
* when either this or the other given CompletableFuture completes, |
2640 |
* after performing the given action from a task running in the |
2641 |
* given executor. |
2642 |
* |
2643 |
* <p>If this and/or the other CompletableFuture complete |
2644 |
* exceptionally, then the returned CompletableFuture may also do so, |
2645 |
* with a CompletionException holding one of these exceptions as its |
2646 |
* cause. No guarantees are made about which result or exception is |
2647 |
* used in the returned CompletableFuture. If the supplied action |
2648 |
* throws an exception, then the returned CompletableFuture completes |
2649 |
* exceptionally with a CompletionException holding the exception as |
2650 |
* its cause. |
2651 |
* |
2652 |
* @param other the other CompletableFuture |
2653 |
* @param action the action to perform before completing the |
2654 |
* returned CompletableFuture |
2655 |
* @param executor the executor to use for asynchronous execution |
2656 |
* @return the new CompletableFuture |
2657 |
*/ |
2658 |
public CompletableFuture<Void> runAfterEitherAsync |
2659 |
(CompletableFuture<?> other, |
2660 |
Runnable action, |
2661 |
Executor executor) { |
2662 |
if (executor == null) throw new NullPointerException(); |
2663 |
return doOrRun(other, action, executor); |
2664 |
} |
2665 |
|
2666 |
private CompletableFuture<Void> doOrRun(CompletableFuture<?> other, |
2667 |
Runnable action, |
2668 |
Executor e) { |
2669 |
if (other == null || action == null) throw new NullPointerException(); |
2670 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2671 |
OrRunCompletion<T> d = null; |
2672 |
Object r; |
2673 |
if ((r = result) == null && (r = other.result) == null) { |
2674 |
d = new OrRunCompletion<T>(this, other, action, dst, e); |
2675 |
CompletionNode q = null, p = new CompletionNode(d); |
2676 |
while ((r = result) == null && (r = other.result) == null) { |
2677 |
if (q != null) { |
2678 |
if (UNSAFE.compareAndSwapObject |
2679 |
(other, COMPLETIONS, q.next = other.completions, q)) |
2680 |
break; |
2681 |
} |
2682 |
else if (UNSAFE.compareAndSwapObject |
2683 |
(this, COMPLETIONS, p.next = completions, p)) |
2684 |
q = new CompletionNode(d); |
2685 |
} |
2686 |
} |
2687 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2688 |
Throwable ex; |
2689 |
if (r instanceof AltResult) |
2690 |
ex = ((AltResult)r).ex; |
2691 |
else |
2692 |
ex = null; |
2693 |
if (ex == null) { |
2694 |
try { |
2695 |
if (e != null) |
2696 |
e.execute(new AsyncRun(action, dst)); |
2697 |
else |
2698 |
action.run(); |
2699 |
} catch (Throwable rex) { |
2700 |
ex = rex; |
2701 |
} |
2702 |
} |
2703 |
if (e == null || ex != null) |
2704 |
dst.internalComplete(null, ex); |
2705 |
} |
2706 |
helpPostComplete(); |
2707 |
other.helpPostComplete(); |
2708 |
return dst; |
2709 |
} |
2710 |
|
2711 |
/** |
2712 |
* Returns a CompletableFuture that upon completion, has the same |
2713 |
* value as produced by the given function of the result of this |
2714 |
* CompletableFuture. |
2715 |
* |
2716 |
* <p>If this CompletableFuture completes exceptionally, then the |
2717 |
* returned CompletableFuture also does so, with a |
2718 |
* CompletionException holding this exception as its cause. |
2719 |
* Similarly, if the computed CompletableFuture completes |
2720 |
* exceptionally, then so does the returned CompletableFuture. |
2721 |
* |
2722 |
* @param fn the function returning a new CompletableFuture |
2723 |
* @return the CompletableFuture |
2724 |
*/ |
2725 |
public <U> CompletableFuture<U> thenCompose |
2726 |
(Function<? super T, CompletableFuture<U>> fn) { |
2727 |
return doCompose(fn, null); |
2728 |
} |
2729 |
|
2730 |
/** |
2731 |
* Returns a CompletableFuture that upon completion, has the same |
2732 |
* value as that produced asynchronously using the {@link |
2733 |
* ForkJoinPool#commonPool()} by the given function of the result |
2734 |
* of this CompletableFuture. |
2735 |
* |
2736 |
* <p>If this CompletableFuture completes exceptionally, then the |
2737 |
* returned CompletableFuture also does so, with a |
2738 |
* CompletionException holding this exception as its cause. |
2739 |
* Similarly, if the computed CompletableFuture completes |
2740 |
* exceptionally, then so does the returned CompletableFuture. |
2741 |
* |
2742 |
* @param fn the function returning a new CompletableFuture |
2743 |
* @return the CompletableFuture |
2744 |
*/ |
2745 |
public <U> CompletableFuture<U> thenComposeAsync |
2746 |
(Function<? super T, CompletableFuture<U>> fn) { |
2747 |
return doCompose(fn, ForkJoinPool.commonPool()); |
2748 |
} |
2749 |
|
2750 |
/** |
2751 |
* Returns a CompletableFuture that upon completion, has the same |
2752 |
* value as that produced asynchronously using the given executor |
2753 |
* by the given function of this CompletableFuture. |
2754 |
* |
2755 |
* <p>If this CompletableFuture completes exceptionally, then the |
2756 |
* returned CompletableFuture also does so, with a |
2757 |
* CompletionException holding this exception as its cause. |
2758 |
* Similarly, if the computed CompletableFuture completes |
2759 |
* exceptionally, then so does the returned CompletableFuture. |
2760 |
* |
2761 |
* @param fn the function returning a new CompletableFuture |
2762 |
* @param executor the executor to use for asynchronous execution |
2763 |
* @return the CompletableFuture |
2764 |
*/ |
2765 |
public <U> CompletableFuture<U> thenComposeAsync |
2766 |
(Function<? super T, CompletableFuture<U>> fn, |
2767 |
Executor executor) { |
2768 |
if (executor == null) throw new NullPointerException(); |
2769 |
return doCompose(fn, executor); |
2770 |
} |
2771 |
|
2772 |
private <U> CompletableFuture<U> doCompose |
2773 |
(Function<? super T, CompletableFuture<U>> fn, |
2774 |
Executor e) { |
2775 |
if (fn == null) throw new NullPointerException(); |
2776 |
CompletableFuture<U> dst = null; |
2777 |
ComposeCompletion<T,U> d = null; |
2778 |
Object r; |
2779 |
if ((r = result) == null) { |
2780 |
dst = new CompletableFuture<U>(); |
2781 |
CompletionNode p = new CompletionNode |
2782 |
(d = new ComposeCompletion<T,U>(this, fn, dst, e)); |
2783 |
while ((r = result) == null) { |
2784 |
if (UNSAFE.compareAndSwapObject |
2785 |
(this, COMPLETIONS, p.next = completions, p)) |
2786 |
break; |
2787 |
} |
2788 |
} |
2789 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2790 |
T t; Throwable ex; |
2791 |
if (r instanceof AltResult) { |
2792 |
ex = ((AltResult)r).ex; |
2793 |
t = null; |
2794 |
} |
2795 |
else { |
2796 |
ex = null; |
2797 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2798 |
t = tr; |
2799 |
} |
2800 |
if (ex == null) { |
2801 |
if (e != null) { |
2802 |
if (dst == null) |
2803 |
dst = new CompletableFuture<U>(); |
2804 |
e.execute(new AsyncCompose<T,U>(t, fn, dst)); |
2805 |
} |
2806 |
else { |
2807 |
try { |
2808 |
if ((dst = fn.apply(t)) == null) |
2809 |
ex = new NullPointerException(); |
2810 |
} catch (Throwable rex) { |
2811 |
ex = rex; |
2812 |
} |
2813 |
if (dst == null) |
2814 |
dst = new CompletableFuture<U>(); |
2815 |
} |
2816 |
} |
2817 |
if (e == null && ex != null) |
2818 |
dst.internalComplete(null, ex); |
2819 |
} |
2820 |
helpPostComplete(); |
2821 |
dst.helpPostComplete(); |
2822 |
return dst; |
2823 |
} |
2824 |
|
2825 |
/** |
2826 |
* Returns a new CompletableFuture that is completed when this |
2827 |
* CompletableFuture completes, with the result of the given |
2828 |
* function of the exception triggering this CompletableFuture's |
2829 |
* completion when it completes exceptionally; otherwise, if this |
2830 |
* CompletableFuture completes normally, then the returned |
2831 |
* CompletableFuture also completes normally with the same value. |
2832 |
* |
2833 |
* @param fn the function to use to compute the value of the |
2834 |
* returned CompletableFuture if this CompletableFuture completed |
2835 |
* exceptionally |
2836 |
* @return the new CompletableFuture |
2837 |
*/ |
2838 |
public CompletableFuture<T> exceptionally |
2839 |
(Function<Throwable, ? extends T> fn) { |
2840 |
if (fn == null) throw new NullPointerException(); |
2841 |
CompletableFuture<T> dst = new CompletableFuture<T>(); |
2842 |
ExceptionCompletion<T> d = null; |
2843 |
Object r; |
2844 |
if ((r = result) == null) { |
2845 |
CompletionNode p = |
2846 |
new CompletionNode(d = new ExceptionCompletion<T>(this, fn, dst)); |
2847 |
while ((r = result) == null) { |
2848 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2849 |
p.next = completions, p)) |
2850 |
break; |
2851 |
} |
2852 |
} |
2853 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2854 |
T t = null; Throwable ex, dx = null; |
2855 |
if (r instanceof AltResult) { |
2856 |
if ((ex = ((AltResult)r).ex) != null) { |
2857 |
try { |
2858 |
t = fn.apply(ex); |
2859 |
} catch (Throwable rex) { |
2860 |
dx = rex; |
2861 |
} |
2862 |
} |
2863 |
} |
2864 |
else { |
2865 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2866 |
t = tr; |
2867 |
} |
2868 |
dst.internalComplete(t, dx); |
2869 |
} |
2870 |
helpPostComplete(); |
2871 |
return dst; |
2872 |
} |
2873 |
|
2874 |
/** |
2875 |
* Returns a new CompletableFuture that is completed when this |
2876 |
* CompletableFuture completes, with the result of the given |
2877 |
* function of the result and exception of this CompletableFuture's |
2878 |
* completion. The given function is invoked with the result (or |
2879 |
* {@code null} if none) and the exception (or {@code null} if none) |
2880 |
* of this CompletableFuture when complete. |
2881 |
* |
2882 |
* @param fn the function to use to compute the value of the |
2883 |
* returned CompletableFuture |
2884 |
* @return the new CompletableFuture |
2885 |
*/ |
2886 |
public <U> CompletableFuture<U> handle |
2887 |
(BiFunction<? super T, Throwable, ? extends U> fn) { |
2888 |
if (fn == null) throw new NullPointerException(); |
2889 |
CompletableFuture<U> dst = new CompletableFuture<U>(); |
2890 |
HandleCompletion<T,U> d = null; |
2891 |
Object r; |
2892 |
if ((r = result) == null) { |
2893 |
CompletionNode p = |
2894 |
new CompletionNode(d = new HandleCompletion<T,U>(this, fn, dst)); |
2895 |
while ((r = result) == null) { |
2896 |
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, |
2897 |
p.next = completions, p)) |
2898 |
break; |
2899 |
} |
2900 |
} |
2901 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
2902 |
T t; Throwable ex; |
2903 |
if (r instanceof AltResult) { |
2904 |
ex = ((AltResult)r).ex; |
2905 |
t = null; |
2906 |
} |
2907 |
else { |
2908 |
ex = null; |
2909 |
@SuppressWarnings("unchecked") T tr = (T) r; |
2910 |
t = tr; |
2911 |
} |
2912 |
U u; Throwable dx; |
2913 |
try { |
2914 |
u = fn.apply(t, ex); |
2915 |
dx = null; |
2916 |
} catch (Throwable rex) { |
2917 |
dx = rex; |
2918 |
u = null; |
2919 |
} |
2920 |
dst.internalComplete(u, dx); |
2921 |
} |
2922 |
helpPostComplete(); |
2923 |
return dst; |
2924 |
} |
2925 |
|
2926 |
|
2927 |
/* ------------- Arbitrary-arity constructions -------------- */ |
2928 |
|
2929 |
/* |
2930 |
* The basic plan of attack is to recursively form binary |
2931 |
* completion trees of elements. This can be overkill for small |
2932 |
* sets, but scales nicely. The And/All vs Or/Any forms use the |
2933 |
* same idea, but details differ. |
2934 |
*/ |
2935 |
|
2936 |
/** |
2937 |
* Returns a new CompletableFuture that is completed when all of |
2938 |
* the given CompletableFutures complete. If any of the given |
2939 |
* CompletableFutures complete exceptionally, then the returned |
2940 |
* CompletableFuture also does so, with a CompletionException |
2941 |
* holding this exception as its cause. Otherwise, the results, |
2942 |
* if any, of the given CompletableFutures are not reflected in |
2943 |
* the returned CompletableFuture, but may be obtained by |
2944 |
* inspecting them individually. If no CompletableFutures are |
2945 |
* provided, returns a CompletableFuture completed with the value |
2946 |
* {@code null}. |
2947 |
* |
2948 |
* <p>Among the applications of this method is to await completion |
2949 |
* of a set of independent CompletableFutures before continuing a |
2950 |
* program, as in: {@code CompletableFuture.allOf(c1, c2, |
2951 |
* c3).join();}. |
2952 |
* |
2953 |
* @param cfs the CompletableFutures |
2954 |
* @return a new CompletableFuture that is completed when all of the |
2955 |
* given CompletableFutures complete |
2956 |
* @throws NullPointerException if the array or any of its elements are |
2957 |
* {@code null} |
2958 |
*/ |
2959 |
public static CompletableFuture<Void> allOf(CompletableFuture<?>... cfs) { |
2960 |
int len = cfs.length; // Directly handle empty and singleton cases |
2961 |
if (len > 1) |
2962 |
return allTree(cfs, 0, len - 1); |
2963 |
else { |
2964 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
2965 |
CompletableFuture<?> f; |
2966 |
if (len == 0) |
2967 |
dst.result = NIL; |
2968 |
else if ((f = cfs[0]) == null) |
2969 |
throw new NullPointerException(); |
2970 |
else { |
2971 |
ThenPropagate d = null; |
2972 |
CompletionNode p = null; |
2973 |
Object r; |
2974 |
while ((r = f.result) == null) { |
2975 |
if (d == null) |
2976 |
d = new ThenPropagate(f, dst); |
2977 |
else if (p == null) |
2978 |
p = new CompletionNode(d); |
2979 |
else if (UNSAFE.compareAndSwapObject |
2980 |
(f, COMPLETIONS, p.next = f.completions, p)) |
2981 |
break; |
2982 |
} |
2983 |
if (r != null && (d == null || d.compareAndSet(0, 1))) |
2984 |
dst.internalComplete(null, (r instanceof AltResult) ? |
2985 |
((AltResult)r).ex : null); |
2986 |
f.helpPostComplete(); |
2987 |
} |
2988 |
return dst; |
2989 |
} |
2990 |
} |
2991 |
|
2992 |
/** |
2993 |
* Recursively constructs an And'ed tree of CompletableFutures. |
2994 |
* Called only when array known to have at least two elements. |
2995 |
*/ |
2996 |
private static CompletableFuture<Void> allTree(CompletableFuture<?>[] cfs, |
2997 |
int lo, int hi) { |
2998 |
CompletableFuture<?> fst, snd; |
2999 |
int mid = (lo + hi) >>> 1; |
3000 |
if ((fst = (lo == mid ? cfs[lo] : allTree(cfs, lo, mid))) == null || |
3001 |
(snd = (hi == mid+1 ? cfs[hi] : allTree(cfs, mid+1, hi))) == null) |
3002 |
throw new NullPointerException(); |
3003 |
CompletableFuture<Void> dst = new CompletableFuture<Void>(); |
3004 |
AndCompletion d = null; |
3005 |
CompletionNode p = null, q = null; |
3006 |
Object r = null, s = null; |
3007 |
while ((r = fst.result) == null || (s = snd.result) == null) { |
3008 |
if (d == null) |
3009 |
d = new AndCompletion(fst, snd, dst); |
3010 |
else if (p == null) |
3011 |
p = new CompletionNode(d); |
3012 |
else if (q == null) { |
3013 |
if (UNSAFE.compareAndSwapObject |
3014 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
3015 |
q = new CompletionNode(d); |
3016 |
} |
3017 |
else if (UNSAFE.compareAndSwapObject |
3018 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
3019 |
break; |
3020 |
} |
3021 |
if ((r != null || (r = fst.result) != null) && |
3022 |
(s != null || (s = snd.result) != null) && |
3023 |
(d == null || d.compareAndSet(0, 1))) { |
3024 |
Throwable ex; |
3025 |
if (r instanceof AltResult) |
3026 |
ex = ((AltResult)r).ex; |
3027 |
else |
3028 |
ex = null; |
3029 |
if (ex == null && (s instanceof AltResult)) |
3030 |
ex = ((AltResult)s).ex; |
3031 |
dst.internalComplete(null, ex); |
3032 |
} |
3033 |
fst.helpPostComplete(); |
3034 |
snd.helpPostComplete(); |
3035 |
return dst; |
3036 |
} |
3037 |
|
3038 |
/** |
3039 |
* Returns a new CompletableFuture that is completed when any of |
3040 |
* the given CompletableFutures complete, with the same result. |
3041 |
* Otherwise, if it completed exceptionally, the returned |
3042 |
* CompletableFuture also does so, with a CompletionException |
3043 |
* holding this exception as its cause. If no CompletableFutures |
3044 |
* are provided, returns an incomplete CompletableFuture. |
3045 |
* |
3046 |
* @param cfs the CompletableFutures |
3047 |
* @return a new CompletableFuture that is completed with the |
3048 |
* result or exception of any of the given CompletableFutures when |
3049 |
* one completes |
3050 |
* @throws NullPointerException if the array or any of its elements are |
3051 |
* {@code null} |
3052 |
*/ |
3053 |
public static CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs) { |
3054 |
int len = cfs.length; // Same idea as allOf |
3055 |
if (len > 1) |
3056 |
return anyTree(cfs, 0, len - 1); |
3057 |
else { |
3058 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
3059 |
CompletableFuture<?> f; |
3060 |
if (len == 0) |
3061 |
; // skip |
3062 |
else if ((f = cfs[0]) == null) |
3063 |
throw new NullPointerException(); |
3064 |
else { |
3065 |
ThenCopy<Object> d = null; |
3066 |
CompletionNode p = null; |
3067 |
Object r; |
3068 |
while ((r = f.result) == null) { |
3069 |
if (d == null) |
3070 |
d = new ThenCopy<Object>(f, dst); |
3071 |
else if (p == null) |
3072 |
p = new CompletionNode(d); |
3073 |
else if (UNSAFE.compareAndSwapObject |
3074 |
(f, COMPLETIONS, p.next = f.completions, p)) |
3075 |
break; |
3076 |
} |
3077 |
if (r != null && (d == null || d.compareAndSet(0, 1))) { |
3078 |
Throwable ex; Object t; |
3079 |
if (r instanceof AltResult) { |
3080 |
ex = ((AltResult)r).ex; |
3081 |
t = null; |
3082 |
} |
3083 |
else { |
3084 |
ex = null; |
3085 |
t = r; |
3086 |
} |
3087 |
dst.internalComplete(t, ex); |
3088 |
} |
3089 |
f.helpPostComplete(); |
3090 |
} |
3091 |
return dst; |
3092 |
} |
3093 |
} |
3094 |
|
3095 |
/** |
3096 |
* Recursively constructs an Or'ed tree of CompletableFutures. |
3097 |
*/ |
3098 |
private static CompletableFuture<Object> anyTree(CompletableFuture<?>[] cfs, |
3099 |
int lo, int hi) { |
3100 |
CompletableFuture<?> fst, snd; |
3101 |
int mid = (lo + hi) >>> 1; |
3102 |
if ((fst = (lo == mid ? cfs[lo] : anyTree(cfs, lo, mid))) == null || |
3103 |
(snd = (hi == mid+1 ? cfs[hi] : anyTree(cfs, mid+1, hi))) == null) |
3104 |
throw new NullPointerException(); |
3105 |
CompletableFuture<Object> dst = new CompletableFuture<Object>(); |
3106 |
OrCompletion d = null; |
3107 |
CompletionNode p = null, q = null; |
3108 |
Object r; |
3109 |
while ((r = fst.result) == null && (r = snd.result) == null) { |
3110 |
if (d == null) |
3111 |
d = new OrCompletion(fst, snd, dst); |
3112 |
else if (p == null) |
3113 |
p = new CompletionNode(d); |
3114 |
else if (q == null) { |
3115 |
if (UNSAFE.compareAndSwapObject |
3116 |
(fst, COMPLETIONS, p.next = fst.completions, p)) |
3117 |
q = new CompletionNode(d); |
3118 |
} |
3119 |
else if (UNSAFE.compareAndSwapObject |
3120 |
(snd, COMPLETIONS, q.next = snd.completions, q)) |
3121 |
break; |
3122 |
} |
3123 |
if ((r != null || (r = fst.result) != null || |
3124 |
(r = snd.result) != null) && |
3125 |
(d == null || d.compareAndSet(0, 1))) { |
3126 |
Throwable ex; Object t; |
3127 |
if (r instanceof AltResult) { |
3128 |
ex = ((AltResult)r).ex; |
3129 |
t = null; |
3130 |
} |
3131 |
else { |
3132 |
ex = null; |
3133 |
t = r; |
3134 |
} |
3135 |
dst.internalComplete(t, ex); |
3136 |
} |
3137 |
fst.helpPostComplete(); |
3138 |
snd.helpPostComplete(); |
3139 |
return dst; |
3140 |
} |
3141 |
|
3142 |
/* ------------- Control and status methods -------------- */ |
3143 |
|
3144 |
/** |
3145 |
* If not already completed, completes this CompletableFuture with |
3146 |
* a {@link CancellationException}. Dependent CompletableFutures |
3147 |
* that have not already completed will also complete |
3148 |
* exceptionally, with a {@link CompletionException} caused by |
3149 |
* this {@code CancellationException}. |
3150 |
* |
3151 |
* @param mayInterruptIfRunning this value has no effect in this |
3152 |
* implementation because interrupts are not used to control |
3153 |
* processing. |
3154 |
* |
3155 |
* @return {@code true} if this task is now cancelled |
3156 |
*/ |
3157 |
public boolean cancel(boolean mayInterruptIfRunning) { |
3158 |
boolean cancelled = (result == null) && |
3159 |
UNSAFE.compareAndSwapObject |
3160 |
(this, RESULT, null, new AltResult(new CancellationException())); |
3161 |
postComplete(); |
3162 |
return cancelled || isCancelled(); |
3163 |
} |
3164 |
|
3165 |
/** |
3166 |
* Returns {@code true} if this CompletableFuture was cancelled |
3167 |
* before it completed normally. |
3168 |
* |
3169 |
* @return {@code true} if this CompletableFuture was cancelled |
3170 |
* before it completed normally |
3171 |
*/ |
3172 |
public boolean isCancelled() { |
3173 |
Object r; |
3174 |
return ((r = result) instanceof AltResult) && |
3175 |
(((AltResult)r).ex instanceof CancellationException); |
3176 |
} |
3177 |
|
3178 |
/** |
3179 |
* Forcibly sets or resets the value subsequently returned by |
3180 |
* method {@link #get()} and related methods, whether or not |
3181 |
* already completed. This method is designed for use only in |
3182 |
* error recovery actions, and even in such situations may result |
3183 |
* in ongoing dependent completions using established versus |
3184 |
* overwritten outcomes. |
3185 |
* |
3186 |
* @param value the completion value |
3187 |
*/ |
3188 |
public void obtrudeValue(T value) { |
3189 |
result = (value == null) ? NIL : value; |
3190 |
postComplete(); |
3191 |
} |
3192 |
|
3193 |
/** |
3194 |
* Forcibly causes subsequent invocations of method {@link #get()} |
3195 |
* and related methods to throw the given exception, whether or |
3196 |
* not already completed. This method is designed for use only in |
3197 |
* recovery actions, and even in such situations may result in |
3198 |
* ongoing dependent completions using established versus |
3199 |
* overwritten outcomes. |
3200 |
* |
3201 |
* @param ex the exception |
3202 |
*/ |
3203 |
public void obtrudeException(Throwable ex) { |
3204 |
if (ex == null) throw new NullPointerException(); |
3205 |
result = new AltResult(ex); |
3206 |
postComplete(); |
3207 |
} |
3208 |
|
3209 |
/** |
3210 |
* Returns the estimated number of CompletableFutures whose |
3211 |
* completions are awaiting completion of this CompletableFuture. |
3212 |
* This method is designed for use in monitoring system state, not |
3213 |
* for synchronization control. |
3214 |
* |
3215 |
* @return the number of dependent CompletableFutures |
3216 |
*/ |
3217 |
public int getNumberOfDependents() { |
3218 |
int count = 0; |
3219 |
for (CompletionNode p = completions; p != null; p = p.next) |
3220 |
++count; |
3221 |
return count; |
3222 |
} |
3223 |
|
3224 |
/** |
3225 |
* Returns a string identifying this CompletableFuture, as well as |
3226 |
* its completion state. The state, in brackets, contains the |
3227 |
* String {@code "Completed Normally"} or the String {@code |
3228 |
* "Completed Exceptionally"}, or the String {@code "Not |
3229 |
* completed"} followed by the number of CompletableFutures |
3230 |
* dependent upon its completion, if any. |
3231 |
* |
3232 |
* @return a string identifying this CompletableFuture, as well as its state |
3233 |
*/ |
3234 |
public String toString() { |
3235 |
Object r = result; |
3236 |
int count; |
3237 |
return super.toString() + |
3238 |
((r == null) ? |
3239 |
(((count = getNumberOfDependents()) == 0) ? |
3240 |
"[Not completed]" : |
3241 |
"[Not completed, " + count + " dependents]") : |
3242 |
(((r instanceof AltResult) && ((AltResult)r).ex != null) ? |
3243 |
"[Completed exceptionally]" : |
3244 |
"[Completed normally]")); |
3245 |
} |
3246 |
|
3247 |
// Unsafe mechanics |
3248 |
private static final sun.misc.Unsafe UNSAFE; |
3249 |
private static final long RESULT; |
3250 |
private static final long WAITERS; |
3251 |
private static final long COMPLETIONS; |
3252 |
static { |
3253 |
try { |
3254 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
3255 |
Class<?> k = CompletableFuture.class; |
3256 |
RESULT = UNSAFE.objectFieldOffset |
3257 |
(k.getDeclaredField("result")); |
3258 |
WAITERS = UNSAFE.objectFieldOffset |
3259 |
(k.getDeclaredField("waiters")); |
3260 |
COMPLETIONS = UNSAFE.objectFieldOffset |
3261 |
(k.getDeclaredField("completions")); |
3262 |
} catch (Exception e) { |
3263 |
throw new Error(e); |
3264 |
} |
3265 |
} |
3266 |
} |