-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathCompletableFuture.java
More file actions
3012 lines (2875 loc) · 110 KB
/
CompletableFuture.java
File metadata and controls
3012 lines (2875 loc) · 110 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
/*
*
*
*
*
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
package java.util.concurrent;
import java.util.function.Supplier;
import java.util.function.Consumer;
import java.util.function.BiConsumer;
import java.util.function.Function;
import java.util.function.BiFunction;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.ForkJoinTask;
import java.util.concurrent.Executor;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CompletionException;
import java.util.concurrent.CompletionStage;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.LockSupport;
/**
* A {@link Future} that may be explicitly completed (setting its
* value and status), and may be used as a {@link CompletionStage},
* supporting dependent functions and actions that trigger upon its
* completion.
*
* <p>When two or more threads attempt to
* {@link #complete complete},
* {@link #completeExceptionally completeExceptionally}, or
* {@link #cancel cancel}
* a CompletableFuture, only one of them succeeds.
*
* <p>In addition to these and related methods for directly
* manipulating status and results, CompletableFuture implements
* interface {@link CompletionStage} with the following policies: <ul>
*
* <li>Actions supplied for dependent completions of
* <em>non-async</em> methods may be performed by the thread that
* completes the current CompletableFuture, or by any other caller of
* a completion method.</li>
*
* <li>All <em>async</em> methods without an explicit Executor
* argument are performed using the {@link ForkJoinPool#commonPool()}
* (unless it does not support a parallelism level of at least two, in
* which case, a new Thread is used). To simplify monitoring,
* debugging, and tracking, all generated asynchronous tasks are
* instances of the marker interface {@link
* AsynchronousCompletionTask}. </li>
*
* <li>All CompletionStage methods are implemented independently of
* other public methods, so the behavior of one method is not impacted
* by overrides of others in subclasses. </li> </ul>
*
* <p>CompletableFuture also implements {@link Future} with the following
* policies: <ul>
*
* <li>Since (unlike {@link FutureTask}) this class has no direct
* control over the computation that causes it to be completed,
* cancellation is treated as just another form of exceptional
* completion. Method {@link #cancel cancel} has the same effect as
* {@code completeExceptionally(new CancellationException())}. Method
* {@link #isCompletedExceptionally} can be used to determine if a
* CompletableFuture completed in any exceptional fashion.</li>
*
* <li>In case of exceptional completion with a CompletionException,
* methods {@link #get()} and {@link #get(long, TimeUnit)} throw an
* {@link ExecutionException} with the same cause as held in the
* corresponding CompletionException. To simplify usage in most
* contexts, this class also defines methods {@link #join()} and
* {@link #getNow} that instead throw the CompletionException directly
* in these cases.</li> </ul>
*
* @author Doug Lea
* @since 1.8
*/
public class CompletableFuture<T> implements Future<T>, CompletionStage<T> {
/*
* Overview:
*
* 1. Non-nullness of field result (set via CAS) indicates done.
* An AltResult is used to box null as a result, as well as to
* hold exceptions. Using a single field makes completion fast
* and simple to detect and trigger, at the expense of a lot of
* encoding and decoding that infiltrates many methods. One minor
* simplification relies on the (static) NIL (to box null results)
* being the only AltResult with a null exception field, so we
* don't usually need explicit comparisons with NIL. The CF
* exception propagation mechanics surrounding decoding rely on
* unchecked casts of decoded results really being unchecked,
* where user type errors are caught at point of use, as is
* currently the case in Java. These are highlighted by using
* SuppressWarnings-annotated temporaries.
*
* 2. Waiters are held in a Treiber stack similar to the one used
* in FutureTask, Phaser, and SynchronousQueue. See their
* internal documentation for algorithmic details.
*
* 3. Completions are also kept in a list/stack, and pulled off
* and run when completion is triggered. (We could even use the
* same stack as for waiters, but would give up the potential
* parallelism obtained because woken waiters help release/run
* others -- see method postComplete). Because post-processing
* may race with direct calls, class Completion opportunistically
* extends AtomicInteger so callers can claim the action via
* compareAndSet(0, 1). The Completion.run methods are all
* written a boringly similar uniform way (that sometimes includes
* unnecessary-looking checks, kept to maintain uniformity).
* There are enough dimensions upon which they differ that
* attempts to factor commonalities while maintaining efficiency
* require more lines of code than they would save.
*
* 4. The exported then/and/or methods do support a bit of
* factoring (see doThenApply etc). They must cope with the
* intrinsic races surrounding addition of a dependent action
* versus performing the action directly because the task is
* already complete. For example, a CF may not be complete upon
* entry, so a dependent completion is added, but by the time it
* is added, the target CF is complete, so must be directly
* executed. This is all done while avoiding unnecessary object
* construction in safe-bypass cases.
*/
// preliminaries
static final class AltResult {
final Throwable ex; // null only for NIL
AltResult(Throwable ex) { this.ex = ex; }
}
static final AltResult NIL = new AltResult(null);
// Fields
volatile Object result; // Either the result or boxed AltResult
volatile WaitNode waiters; // Treiber stack of threads blocked on get()
volatile CompletionNode completions; // list (Treiber stack) of completions
// Basic utilities for triggering and processing completions
/**
* Removes and signals all waiting threads and runs all completions.
*/
final void postComplete() {
WaitNode q; Thread t;
while ((q = waiters) != null) {
if (UNSAFE.compareAndSwapObject(this, WAITERS, q, q.next) &&
(t = q.thread) != null) {
q.thread = null;
LockSupport.unpark(t);
}
}
CompletionNode h; Completion c;
while ((h = completions) != null) {
if (UNSAFE.compareAndSwapObject(this, COMPLETIONS, h, h.next) &&
(c = h.completion) != null)
c.run();
}
}
/**
* Triggers completion with the encoding of the given arguments:
* if the exception is non-null, encodes it as a wrapped
* CompletionException unless it is one already. Otherwise uses
* the given result, boxed as NIL if null.
*/
final void internalComplete(T v, Throwable ex) {
if (result == null)
UNSAFE.compareAndSwapObject
(this, RESULT, null,
(ex == null) ? (v == null) ? NIL : v :
new AltResult((ex instanceof CompletionException) ? ex :
new CompletionException(ex)));
postComplete(); // help out even if not triggered
}
/**
* If triggered, helps release and/or process completions.
*/
final void helpPostComplete() {
if (result != null)
postComplete();
}
/* ------------- waiting for completions -------------- */
/** Number of processors, for spin control */
static final int NCPU = Runtime.getRuntime().availableProcessors();
/**
* Heuristic spin value for waitingGet() before blocking on
* multiprocessors
*/
static final int SPINS = (NCPU > 1) ? 1 << 8 : 0;
/**
* Linked nodes to record waiting threads in a Treiber stack. See
* other classes such as Phaser and SynchronousQueue for more
* detailed explanation. This class implements ManagedBlocker to
* avoid starvation when blocking actions pile up in
* ForkJoinPools.
*/
static final class WaitNode implements ForkJoinPool.ManagedBlocker {
long nanos; // wait time if timed
final long deadline; // non-zero if timed
volatile int interruptControl; // > 0: interruptible, < 0: interrupted
volatile Thread thread;
volatile WaitNode next;
WaitNode(boolean interruptible, long nanos, long deadline) {
this.thread = Thread.currentThread();
this.interruptControl = interruptible ? 1 : 0;
this.nanos = nanos;
this.deadline = deadline;
}
public boolean isReleasable() {
if (thread == null)
return true;
if (Thread.interrupted()) {
int i = interruptControl;
interruptControl = -1;
if (i > 0)
return true;
}
if (deadline != 0L &&
(nanos <= 0L || (nanos = deadline - System.nanoTime()) <= 0L)) {
thread = null;
return true;
}
return false;
}
public boolean block() {
if (isReleasable())
return true;
else if (deadline == 0L)
LockSupport.park(this);
else if (nanos > 0L)
LockSupport.parkNanos(this, nanos);
return isReleasable();
}
}
/**
* Returns raw result after waiting, or null if interruptible and
* interrupted.
*/
private Object waitingGet(boolean interruptible) {
WaitNode q = null;
boolean queued = false;
int spins = SPINS;
for (Object r;;) {
if ((r = result) != null) {
if (q != null) { // suppress unpark
q.thread = null;
if (q.interruptControl < 0) {
if (interruptible) {
removeWaiter(q);
return null;
}
Thread.currentThread().interrupt();
}
}
postComplete(); // help release others
return r;
}
else if (spins > 0) {
int rnd = ThreadLocalRandom.nextSecondarySeed();
if (rnd == 0)
rnd = ThreadLocalRandom.current().nextInt();
if (rnd >= 0)
--spins;
}
else if (q == null)
q = new WaitNode(interruptible, 0L, 0L);
else if (!queued)
queued = UNSAFE.compareAndSwapObject(this, WAITERS,
q.next = waiters, q);
else if (interruptible && q.interruptControl < 0) {
removeWaiter(q);
return null;
}
else if (q.thread != null && result == null) {
try {
ForkJoinPool.managedBlock(q);
} catch (InterruptedException ex) {
q.interruptControl = -1;
}
}
}
}
/**
* Awaits completion or aborts on interrupt or timeout.
*
* @param nanos time to wait
* @return raw result
*/
private Object timedAwaitDone(long nanos)
throws InterruptedException, TimeoutException {
WaitNode q = null;
boolean queued = false;
for (Object r;;) {
if ((r = result) != null) {
if (q != null) {
q.thread = null;
if (q.interruptControl < 0) {
removeWaiter(q);
throw new InterruptedException();
}
}
postComplete();
return r;
}
else if (q == null) {
if (nanos <= 0L)
throw new TimeoutException();
long d = System.nanoTime() + nanos;
q = new WaitNode(true, nanos, d == 0L ? 1L : d); // avoid 0
}
else if (!queued)
queued = UNSAFE.compareAndSwapObject(this, WAITERS,
q.next = waiters, q);
else if (q.interruptControl < 0) {
removeWaiter(q);
throw new InterruptedException();
}
else if (q.nanos <= 0L) {
if (result == null) {
removeWaiter(q);
throw new TimeoutException();
}
}
else if (q.thread != null && result == null) {
try {
ForkJoinPool.managedBlock(q);
} catch (InterruptedException ex) {
q.interruptControl = -1;
}
}
}
}
/**
* Tries to unlink a timed-out or interrupted wait node to avoid
* accumulating garbage. Internal nodes are simply unspliced
* without CAS since it is harmless if they are traversed anyway
* by releasers. To avoid effects of unsplicing from already
* removed nodes, the list is retraversed in case of an apparent
* race. This is slow when there are a lot of nodes, but we don't
* expect lists to be long enough to outweigh higher-overhead
* schemes.
*/
private void removeWaiter(WaitNode node) {
if (node != null) {
node.thread = null;
retry:
for (;;) { // restart on removeWaiter race
for (WaitNode pred = null, q = waiters, s; q != null; q = s) {
s = q.next;
if (q.thread != null)
pred = q;
else if (pred != null) {
pred.next = s;
if (pred.thread == null) // check for race
continue retry;
}
else if (!UNSAFE.compareAndSwapObject(this, WAITERS, q, s))
continue retry;
}
break;
}
}
}
/* ------------- Async tasks -------------- */
/**
* A marker interface identifying asynchronous tasks produced by
* {@code async} methods. This may be useful for monitoring,
* debugging, and tracking asynchronous activities.
*
* @since 1.8
*/
public static interface AsynchronousCompletionTask {
}
/** Base class can act as either FJ or plain Runnable */
@SuppressWarnings("serial")
abstract static class Async extends ForkJoinTask<Void>
implements Runnable, AsynchronousCompletionTask {
public final Void getRawResult() { return null; }
public final void setRawResult(Void v) { }
public final void run() { exec(); }
}
/**
* Starts the given async task using the given executor, unless
* the executor is ForkJoinPool.commonPool and it has been
* disabled, in which case starts a new thread.
*/
static void execAsync(Executor e, Async r) {
if (e == ForkJoinPool.commonPool() &&
ForkJoinPool.getCommonPoolParallelism() <= 1)
new Thread(r).start();
else
e.execute(r);
}
static final class AsyncRun extends Async {
final Runnable fn;
final CompletableFuture<Void> dst;
AsyncRun(Runnable fn, CompletableFuture<Void> dst) {
this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<Void> d; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
fn.run();
ex = null;
} catch (Throwable rex) {
ex = rex;
}
d.internalComplete(null, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncSupply<U> extends Async {
final Supplier<U> fn;
final CompletableFuture<U> dst;
AsyncSupply(Supplier<U> fn, CompletableFuture<U> dst) {
this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<U> d; U u; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
u = fn.get();
ex = null;
} catch (Throwable rex) {
ex = rex;
u = null;
}
d.internalComplete(u, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncApply<T,U> extends Async {
final T arg;
final Function<? super T,? extends U> fn;
final CompletableFuture<U> dst;
AsyncApply(T arg, Function<? super T,? extends U> fn,
CompletableFuture<U> dst) {
this.arg = arg; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<U> d; U u; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
u = fn.apply(arg);
ex = null;
} catch (Throwable rex) {
ex = rex;
u = null;
}
d.internalComplete(u, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncCombine<T,U,V> extends Async {
final T arg1;
final U arg2;
final BiFunction<? super T,? super U,? extends V> fn;
final CompletableFuture<V> dst;
AsyncCombine(T arg1, U arg2,
BiFunction<? super T,? super U,? extends V> fn,
CompletableFuture<V> dst) {
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<V> d; V v; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
v = fn.apply(arg1, arg2);
ex = null;
} catch (Throwable rex) {
ex = rex;
v = null;
}
d.internalComplete(v, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncAccept<T> extends Async {
final T arg;
final Consumer<? super T> fn;
final CompletableFuture<?> dst;
AsyncAccept(T arg, Consumer<? super T> fn,
CompletableFuture<?> dst) {
this.arg = arg; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<?> d; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
fn.accept(arg);
ex = null;
} catch (Throwable rex) {
ex = rex;
}
d.internalComplete(null, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncAcceptBoth<T,U> extends Async {
final T arg1;
final U arg2;
final BiConsumer<? super T,? super U> fn;
final CompletableFuture<?> dst;
AsyncAcceptBoth(T arg1, U arg2,
BiConsumer<? super T,? super U> fn,
CompletableFuture<?> dst) {
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<?> d; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
fn.accept(arg1, arg2);
ex = null;
} catch (Throwable rex) {
ex = rex;
}
d.internalComplete(null, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncCompose<T,U> extends Async {
final T arg;
final Function<? super T, ? extends CompletionStage<U>> fn;
final CompletableFuture<U> dst;
AsyncCompose(T arg,
Function<? super T, ? extends CompletionStage<U>> fn,
CompletableFuture<U> dst) {
this.arg = arg; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<U> d, fr; U u; Throwable ex;
if ((d = this.dst) != null && d.result == null) {
try {
CompletionStage<U> cs = fn.apply(arg);
fr = (cs == null) ? null : cs.toCompletableFuture();
ex = (fr == null) ? new NullPointerException() : null;
} catch (Throwable rex) {
ex = rex;
fr = null;
}
if (ex != null)
u = null;
else {
Object r = fr.result;
if (r == null)
r = fr.waitingGet(false);
if (r instanceof AltResult) {
ex = ((AltResult)r).ex;
u = null;
}
else {
@SuppressWarnings("unchecked") U ur = (U) r;
u = ur;
}
}
d.internalComplete(u, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class AsyncWhenComplete<T> extends Async {
final T arg1;
final Throwable arg2;
final BiConsumer<? super T,? super Throwable> fn;
final CompletableFuture<T> dst;
AsyncWhenComplete(T arg1, Throwable arg2,
BiConsumer<? super T,? super Throwable> fn,
CompletableFuture<T> dst) {
this.arg1 = arg1; this.arg2 = arg2; this.fn = fn; this.dst = dst;
}
public final boolean exec() {
CompletableFuture<T> d;
if ((d = this.dst) != null && d.result == null) {
Throwable ex = arg2;
try {
fn.accept(arg1, ex);
} catch (Throwable rex) {
if (ex == null)
ex = rex;
}
d.internalComplete(arg1, ex);
}
return true;
}
private static final long serialVersionUID = 5232453952276885070L;
}
/* ------------- Completions -------------- */
/**
* Simple linked list nodes to record completions, used in
* basically the same way as WaitNodes. (We separate nodes from
* the Completions themselves mainly because for the And and Or
* methods, the same Completion object resides in two lists.)
*/
static final class CompletionNode {
final Completion completion;
volatile CompletionNode next;
CompletionNode(Completion completion) { this.completion = completion; }
}
// Opportunistically subclass AtomicInteger to use compareAndSet to claim.
@SuppressWarnings("serial")
abstract static class Completion extends AtomicInteger implements Runnable {
}
static final class ThenApply<T,U> extends Completion {
final CompletableFuture<? extends T> src;
final Function<? super T,? extends U> fn;
final CompletableFuture<U> dst;
final Executor executor;
ThenApply(CompletableFuture<? extends T> src,
Function<? super T,? extends U> fn,
CompletableFuture<U> dst,
Executor executor) {
this.src = src; this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<? extends T> a;
final Function<? super T,? extends U> fn;
final CompletableFuture<U> dst;
Object r; T t; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult) {
ex = ((AltResult)r).ex;
t = null;
}
else {
ex = null;
@SuppressWarnings("unchecked") T tr = (T) r;
t = tr;
}
Executor e = executor;
U u = null;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncApply<T,U>(t, fn, dst));
else
u = fn.apply(t);
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(u, ex);
}
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class ThenAccept<T> extends Completion {
final CompletableFuture<? extends T> src;
final Consumer<? super T> fn;
final CompletableFuture<?> dst;
final Executor executor;
ThenAccept(CompletableFuture<? extends T> src,
Consumer<? super T> fn,
CompletableFuture<?> dst,
Executor executor) {
this.src = src; this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<? extends T> a;
final Consumer<? super T> fn;
final CompletableFuture<?> dst;
Object r; T t; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult) {
ex = ((AltResult)r).ex;
t = null;
}
else {
ex = null;
@SuppressWarnings("unchecked") T tr = (T) r;
t = tr;
}
Executor e = executor;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncAccept<T>(t, fn, dst));
else
fn.accept(t);
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(null, ex);
}
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class ThenRun extends Completion {
final CompletableFuture<?> src;
final Runnable fn;
final CompletableFuture<Void> dst;
final Executor executor;
ThenRun(CompletableFuture<?> src,
Runnable fn,
CompletableFuture<Void> dst,
Executor executor) {
this.src = src; this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<?> a;
final Runnable fn;
final CompletableFuture<Void> dst;
Object r; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult)
ex = ((AltResult)r).ex;
else
ex = null;
Executor e = executor;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncRun(fn, dst));
else
fn.run();
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(null, ex);
}
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class ThenCombine<T,U,V> extends Completion {
final CompletableFuture<? extends T> src;
final CompletableFuture<? extends U> snd;
final BiFunction<? super T,? super U,? extends V> fn;
final CompletableFuture<V> dst;
final Executor executor;
ThenCombine(CompletableFuture<? extends T> src,
CompletableFuture<? extends U> snd,
BiFunction<? super T,? super U,? extends V> fn,
CompletableFuture<V> dst,
Executor executor) {
this.src = src; this.snd = snd;
this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<? extends T> a;
final CompletableFuture<? extends U> b;
final BiFunction<? super T,? super U,? extends V> fn;
final CompletableFuture<V> dst;
Object r, s; T t; U u; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
(b = this.snd) != null &&
(s = b.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult) {
ex = ((AltResult)r).ex;
t = null;
}
else {
ex = null;
@SuppressWarnings("unchecked") T tr = (T) r;
t = tr;
}
if (ex != null)
u = null;
else if (s instanceof AltResult) {
ex = ((AltResult)s).ex;
u = null;
}
else {
@SuppressWarnings("unchecked") U us = (U) s;
u = us;
}
Executor e = executor;
V v = null;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncCombine<T,U,V>(t, u, fn, dst));
else
v = fn.apply(t, u);
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(v, ex);
}
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class ThenAcceptBoth<T,U> extends Completion {
final CompletableFuture<? extends T> src;
final CompletableFuture<? extends U> snd;
final BiConsumer<? super T,? super U> fn;
final CompletableFuture<Void> dst;
final Executor executor;
ThenAcceptBoth(CompletableFuture<? extends T> src,
CompletableFuture<? extends U> snd,
BiConsumer<? super T,? super U> fn,
CompletableFuture<Void> dst,
Executor executor) {
this.src = src; this.snd = snd;
this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<? extends T> a;
final CompletableFuture<? extends U> b;
final BiConsumer<? super T,? super U> fn;
final CompletableFuture<Void> dst;
Object r, s; T t; U u; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
(b = this.snd) != null &&
(s = b.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult) {
ex = ((AltResult)r).ex;
t = null;
}
else {
ex = null;
@SuppressWarnings("unchecked") T tr = (T) r;
t = tr;
}
if (ex != null)
u = null;
else if (s instanceof AltResult) {
ex = ((AltResult)s).ex;
u = null;
}
else {
@SuppressWarnings("unchecked") U us = (U) s;
u = us;
}
Executor e = executor;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncAcceptBoth<T,U>(t, u, fn, dst));
else
fn.accept(t, u);
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(null, ex);
}
}
private static final long serialVersionUID = 5232453952276885070L;
}
static final class RunAfterBoth extends Completion {
final CompletableFuture<?> src;
final CompletableFuture<?> snd;
final Runnable fn;
final CompletableFuture<Void> dst;
final Executor executor;
RunAfterBoth(CompletableFuture<?> src,
CompletableFuture<?> snd,
Runnable fn,
CompletableFuture<Void> dst,
Executor executor) {
this.src = src; this.snd = snd;
this.fn = fn; this.dst = dst;
this.executor = executor;
}
public final void run() {
final CompletableFuture<?> a;
final CompletableFuture<?> b;
final Runnable fn;
final CompletableFuture<Void> dst;
Object r, s; Throwable ex;
if ((dst = this.dst) != null &&
(fn = this.fn) != null &&
(a = this.src) != null &&
(r = a.result) != null &&
(b = this.snd) != null &&
(s = b.result) != null &&
compareAndSet(0, 1)) {
if (r instanceof AltResult)
ex = ((AltResult)r).ex;
else
ex = null;
if (ex == null && (s instanceof AltResult))
ex = ((AltResult)s).ex;
Executor e = executor;
if (ex == null) {
try {
if (e != null)
execAsync(e, new AsyncRun(fn, dst));
else
fn.run();
} catch (Throwable rex) {
ex = rex;
}
}
if (e == null || ex != null)
dst.internalComplete(null, ex);
}