1 /*
2 * Copyright (c) 2021, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test id=platform
26 * @summary Basic tests for ThreadFlock
27 * @modules java.base/jdk.internal.misc
28 * @run junit/othervm -DthreadFactory=platform ThreadFlockTest
29 */
30
31 /*
32 * @test id=virtual
33 * @modules java.base/jdk.internal.misc
34 * @run junit/othervm -DthreadFactory=virtual ThreadFlockTest
35 */
36
37 import java.time.Duration;
38 import java.util.*;
39 import java.util.function.Function;
40 import java.util.concurrent.*;
41 import java.util.concurrent.atomic.AtomicBoolean;
42 import java.util.concurrent.atomic.AtomicReference;
43 import java.util.stream.Collectors;
44 import java.util.stream.Stream;
45 import jdk.internal.misc.ThreadFlock;
46
47 import org.junit.jupiter.api.Test;
48 import org.junit.jupiter.api.BeforeAll;
49 import org.junit.jupiter.api.AfterAll;
50 import org.junit.jupiter.params.ParameterizedTest;
51 import org.junit.jupiter.params.provider.MethodSource;
52 import static org.junit.jupiter.api.Assertions.*;
53
54 class ThreadFlockTest {
55 private static ScheduledExecutorService scheduler;
56 private static List<ThreadFactory> threadFactories;
57
58 @BeforeAll
59 static void setup() throws Exception {
60 scheduler = Executors.newSingleThreadScheduledExecutor();
61
62 // thread factories
63 String value = System.getProperty("threadFactory");
64 List<ThreadFactory> list = new ArrayList<>();
65 if (value == null || value.equals("platform"))
66 list.add(Thread.ofPlatform().factory());
67 if (value == null || value.equals("virtual"))
68 list.add(Thread.ofVirtual().factory());
69 assertTrue(list.size() > 0, "No thread factories for tests");
70 threadFactories = list;
71 }
72
73 @AfterAll
74 static void shutdown() {
75 scheduler.shutdown();
76 }
77
78 private static Stream<ThreadFactory> factories() {
79 return threadFactories.stream();
80 }
81
82 /**
83 * Test ThreadFlock::name.
84 */
85 @Test
86 void testName() {
87 try (var flock = ThreadFlock.open(null)) {
88 assertNull(flock.name());
89 flock.close();
90 assertNull(flock.name()); // after close
91 }
92 try (var flock = ThreadFlock.open("fetcher")) {
93 assertEquals("fetcher", flock.name());
94 flock.close();
95 assertEquals("fetcher", flock.name()); // after close
96 }
97 }
98
99 /**
100 * Test ThreadFlock::owner.
101 */
102 @Test
103 void testOwner() {
104 try (var flock = ThreadFlock.open(null)) {
105 assertTrue(flock.owner() == Thread.currentThread());
106 flock.close();
107 assertTrue(flock.owner() == Thread.currentThread()); // after close
108 }
109 }
110
111 /**
112 * Test ThreadFlock::isXXXX methods.
113 */
114 @Test
115 void testState() {
116 try (var flock = ThreadFlock.open(null)) {
117 assertFalse(flock.isShutdown());
118 assertFalse(flock.isClosed());
119 flock.close();
120 assertTrue(flock.isShutdown());
121 assertTrue(flock.isClosed());
122 }
123 try (var flock = ThreadFlock.open(null)) {
124 flock.shutdown();
125 assertTrue(flock.isShutdown());
126 assertFalse(flock.isClosed());
127 flock.close();
128 assertTrue(flock.isShutdown());
129 assertTrue(flock.isClosed());
130 }
131 }
132
133 /**
134 * Test ThreadFlock::threads enumerates all threads.
135 */
136 @ParameterizedTest
137 @MethodSource("factories")
138 void testThreads(ThreadFactory factory) {
139 CountDownLatch latch = new CountDownLatch(1);
140 var exception = new AtomicReference<Exception>();
141 Runnable awaitLatch = () -> {
142 try {
143 latch.await();
144 } catch (Exception e) {
145 exception.compareAndSet(null, e);
146 }
147 };
148
149 var flock = ThreadFlock.open(null);
150 try {
151 assertTrue(flock.threads().count() == 0);
152
153 // start 100 threads
154 Set<Thread> threads = new HashSet<>();
155 for (int i = 0; i < 100; i++) {
156 Thread thread = factory.newThread(awaitLatch);
157 flock.start(thread);
158 threads.add(thread);
159 }
160
161 // check thread ThreadFlock::threads enumerates all threads
162 assertEquals(flock.threads().collect(Collectors.toSet()), threads);
163
164 } finally {
165 latch.countDown(); // release threads
166 flock.close();
167 }
168 assertTrue(flock.threads().count() == 0);
169 assertNull(exception.get());
170 }
171
172 /**
173 * Test ThreadFlock::containsThread with nested flocks.
174 */
175 @ParameterizedTest
176 @MethodSource("factories")
177 void testContainsThread1(ThreadFactory factory) {
178 CountDownLatch latch = new CountDownLatch(1);
179 var exception = new AtomicReference<Exception>();
180
181 Runnable awaitLatch = () -> {
182 try {
183 latch.await();
184 } catch (Exception e) {
185 exception.compareAndSet(null, e);
186 }
187 };
188
189 try (var flock1 = ThreadFlock.open(null)) {
190 var flock2 = ThreadFlock.open(null);
191 try {
192 Thread currentThread = Thread.currentThread();
193 assertFalse(flock1.containsThread(currentThread));
194 assertFalse(flock2.containsThread(currentThread));
195
196 // start thread1 in flock1
197 Thread thread1 = factory.newThread(awaitLatch);
198 flock1.start(thread1);
199
200 // start thread2 in flock2
201 Thread thread2 = factory.newThread(awaitLatch);
202 flock2.start(thread2);
203
204 assertTrue(flock1.containsThread(thread1));
205 assertTrue(flock1.containsThread(thread2));
206 assertFalse(flock2.containsThread(thread1));
207 assertTrue(flock2.containsThread(thread2));
208
209 } finally {
210 latch.countDown(); // release threads
211 flock2.close();
212 }
213 }
214 }
215
216 /**
217 * Test ThreadFlock::containsThread with a tree of flocks.
218 */
219 @ParameterizedTest
220 @MethodSource("factories")
221 void testContainsThread2(ThreadFactory factory) throws Exception {
222 CountDownLatch latch = new CountDownLatch(1);
223 var exception = new AtomicReference<Exception>();
224
225 Runnable awaitLatch = () -> {
226 try {
227 latch.await();
228 } catch (Exception e) {
229 exception.compareAndSet(null, e);
230 }
231 };
232
233 try (var flock1 = ThreadFlock.open(null)) {
234
235 // use box to publish to enclosing scope
236 class Box {
237 volatile ThreadFlock flock2;
238 volatile Thread thread2;
239 }
240 var box = new Box();
241
242 // flock1 will be "parent" of flock2
243 Thread thread1 = factory.newThread(() -> {
244 try (var flock2 = ThreadFlock.open(null)) {
245 Thread thread2 = factory.newThread(awaitLatch);
246 flock2.start(thread2);
247 box.flock2 = flock2;
248 box.thread2 = thread2;
249 }
250 });
251 flock1.start(thread1);
252
253 // wait for thread2 to start
254 ThreadFlock flock2;
255 Thread thread2;
256 while ((flock2 = box.flock2) == null || (thread2 = box.thread2) == null) {
257 Thread.sleep(20);
258 }
259
260 try {
261 assertTrue(flock1.containsThread(thread1));
262 assertTrue(flock1.containsThread(thread2));
263 assertFalse(flock2.containsThread(thread1));
264 assertTrue(flock2.containsThread(thread2));
265 } finally {
266 latch.countDown(); // release threads
267 }
268 }
269 }
270
271 /**
272 * Test that start causes a thread to execute.
273 */
274 @ParameterizedTest
275 @MethodSource("factories")
276 void testStart(ThreadFactory factory) throws Exception {
277 try (var flock = ThreadFlock.open(null)) {
278 AtomicBoolean executed = new AtomicBoolean();
279 Thread thread = factory.newThread(() -> executed.set(true));
280 assertTrue(flock.start(thread) == thread);
281 thread.join();
282 assertTrue(executed.get());
283 }
284 }
285
286 /**
287 * Test that start throws IllegalStateException when shutdown
288 */
289 @ParameterizedTest
290 @MethodSource("factories")
291 void testStartAfterShutdown(ThreadFactory factory) {
292 try (var flock = ThreadFlock.open(null)) {
293 flock.shutdown();
294 Thread thread = factory.newThread(() -> { });
295 assertThrows(IllegalStateException.class, () -> flock.start(thread));
296 }
297 }
298
299 /**
300 * Test that start throws IllegalStateException when closed
301 */
302 @ParameterizedTest
303 @MethodSource("factories")
304 void testStartAfterClose(ThreadFactory factory) {
305 var flock = ThreadFlock.open(null);
306 flock.close();;
307 Thread thread = factory.newThread(() -> { });
308 assertThrows(IllegalStateException.class, () -> flock.start(thread));
309 }
310
311 /**
312 * Test that start throws IllegalThreadStateException when invoked to
313 * start a thread that has already started.
314 */
315 @ParameterizedTest
316 @MethodSource("factories")
317 void testStartAfterStarted(ThreadFactory factory) {
318 try (var flock = ThreadFlock.open(null)) {
319 Thread thread = factory.newThread(() -> { });
320 flock.start(thread);
321 assertThrows(IllegalThreadStateException.class, () -> flock.start(thread));
322 }
323 }
324
325 /**
326 * Test start is confined to threads in the flock.
327 */
328 @ParameterizedTest
329 @MethodSource("factories")
330 void testStartConfined(ThreadFactory factory) throws Exception {
331 try (var flock = ThreadFlock.open(null)) {
332 // thread in flock
333 testStartConfined(flock, task -> {
334 Thread thread = factory.newThread(task);
335 return flock.start(thread);
336 });
337
338 // thread in flock
339 try (var flock2 = ThreadFlock.open(null)) {
340 testStartConfined(flock, task -> {
341 Thread thread = factory.newThread(task);
342 return flock2.start(thread);
343 });
344 }
345
346 // thread not contained in flock
347 testStartConfined(flock, task -> {
348 Thread thread = factory.newThread(task);
349 thread.start();
350 return thread;
351 });
352 }
353 }
354
355 /**
356 * Test that a thread created with the given factory cannot start a thread
357 * in the given flock.
358 */
359 private void testStartConfined(ThreadFlock flock,
360 Function<Runnable, Thread> factory) throws Exception {
361 var exception = new AtomicReference<Exception>();
362 Thread thread = factory.apply(() -> {
363 try {
364 Thread t = Thread.ofVirtual().unstarted(() -> { });
365 flock.start(t);
366 } catch (Exception e) {
367 exception.set(e);
368 }
369 });
370 thread.join();
371 Throwable cause = exception.get();
372 if (flock.containsThread(thread)) {
373 assertNull(cause);
374 } else {
375 assertTrue(cause instanceof WrongThreadException);
376 }
377 }
378
379 /**
380 * Test awaitAll with no threads.
381 */
382 @Test
383 void testAwaitAllWithNoThreads() throws Exception {
384 try (var flock = ThreadFlock.open(null)) {
385 assertTrue(flock.awaitAll());
386 assertTrue(flock.awaitAll(Duration.ofSeconds(1)));
387 }
388 }
389
390 /**
391 * Test awaitAll with threads running.
392 */
393 @ParameterizedTest
394 @MethodSource("factories")
395 void testAwaitAllWithThreads(ThreadFactory factory) throws Exception {
396 try (var flock = ThreadFlock.open(null)) {
397 AtomicBoolean done = new AtomicBoolean();
398 Runnable task = () -> {
399 try {
400 Thread.sleep(Duration.ofMillis(50));
401 done.set(true);
402 } catch (InterruptedException e) { }
403 };
404 Thread thread = factory.newThread(task);
405 flock.start(thread);
406 assertTrue(flock.awaitAll());
407 assertTrue(done.get());
408 }
409 }
410
411 /**
412 * Test awaitAll with timeout, threads finish before timeout expires.
413 */
414 @ParameterizedTest
415 @MethodSource("factories")
416 void testAwaitAllWithTimeout1(ThreadFactory factory) throws Exception {
417 try (var flock = ThreadFlock.open(null)) {
418 Runnable task = () -> {
419 try {
420 Thread.sleep(Duration.ofSeconds(2));
421 } catch (InterruptedException e) { }
422 };
423 Thread thread = factory.newThread(task);
424 flock.start(thread);
425
426 long startMillis = millisTime();
427 boolean done = flock.awaitAll(Duration.ofSeconds(30));
428 assertTrue(done);
429 checkDuration(startMillis, 1900, 4000);
430 }
431 }
432
433 /**
434 * Test awaitAll with timeout, timeout expires before threads finish.
435 */
436 @ParameterizedTest
437 @MethodSource("factories")
438 void testAwaitAllWithTimeout2(ThreadFactory factory) throws Exception {
439 try (var flock = ThreadFlock.open(null)) {
440 var latch = new CountDownLatch(1);
441
442 Runnable task = () -> {
443 try {
444 latch.await();
445 } catch (InterruptedException e) { }
446 };
447 Thread thread = factory.newThread(task);
448 flock.start(thread);
449
450 try {
451 long startMillis = millisTime();
452 try {
453 flock.awaitAll(Duration.ofSeconds(2));
454 fail("awaitAll did not throw");
455 } catch (TimeoutException e) {
456 checkDuration(startMillis, 1900, 4000);
457 }
458 } finally {
459 latch.countDown();
460 }
461 }
462 }
463
464 /**
465 * Test awaitAll with timeout many times.
466 */
467 @ParameterizedTest
468 @MethodSource("factories")
469 void testAwaitAllWithTimeout3(ThreadFactory factory) throws Exception {
470 try (var flock = ThreadFlock.open(null)) {
471 var latch = new CountDownLatch(1);
472
473 Runnable task = () -> {
474 try {
475 latch.await();
476 } catch (InterruptedException e) { }
477 };
478 Thread thread = factory.newThread(task);
479 flock.start(thread);
480
481 try {
482 for (int i = 0; i < 3; i++) {
483 try {
484 flock.awaitAll(Duration.ofMillis(50));
485 fail("awaitAll did not throw");
486 } catch (TimeoutException expected) { }
487 }
488 } finally {
489 latch.countDown();
490 }
491
492 boolean done = flock.awaitAll();
493 assertTrue(done);
494 }
495 }
496
497 /**
498 * Test awaitAll with a 0 or negative timeout.
499 */
500 @ParameterizedTest
501 @MethodSource("factories")
502 void testAwaitAllWithTimeout4(ThreadFactory factory) throws Exception {
503 try (var flock = ThreadFlock.open(null)) {
504 var latch = new CountDownLatch(1);
505
506 Runnable task = () -> {
507 try {
508 latch.await();
509 } catch (InterruptedException e) { }
510 };
511 Thread thread = factory.newThread(task);
512 flock.start(thread);
513
514 try {
515 try {
516 flock.awaitAll(Duration.ofSeconds(0));
517 fail("awaitAll did not throw");
518 } catch (TimeoutException expected) { }
519 try {
520 flock.awaitAll(Duration.ofSeconds(-1));
521 fail("awaitAll did not throw");
522 } catch (TimeoutException expected) { }
523 } finally {
524 latch.countDown();
525 }
526
527 boolean done = flock.awaitAll();
528 assertTrue(done);
529 }
530 }
531
532 /**
533 * Test awaitAll with interrupt status set, should interrupt thread.
534 */
535 @ParameterizedTest
536 @MethodSource("factories")
537 void testInterruptAwaitAll1(ThreadFactory factory) {
538 CountDownLatch latch = new CountDownLatch(1);
539 var exception = new AtomicReference<Exception>();
540 Runnable awaitLatch = () -> {
541 try {
542 latch.await();
543 } catch (Exception e) {
544 exception.compareAndSet(null, e);
545 }
546 };
547
548 var flock = ThreadFlock.open(null);
549 try {
550 Thread thread = factory.newThread(awaitLatch);
551 flock.start(thread);
552
553 // invoke awaitAll with interrupt status set.
554 Thread.currentThread().interrupt();
555 try {
556 flock.awaitAll();
557 fail("awaitAll did not throw");
558 } catch (InterruptedException e) {
559 // interrupt status should be clear
560 assertFalse(Thread.currentThread().isInterrupted());
561 }
562
563 // invoke awaitAll(Duration) with interrupt status set.
564 Thread.currentThread().interrupt();
565 try {
566 flock.awaitAll(Duration.ofSeconds(30));
567 fail("awaitAll did not throw");
568 } catch (TimeoutException e) {
569 fail("TimeoutException not expected");
570 } catch (InterruptedException e) {
571 // interrupt status should be clear
572 assertFalse(Thread.currentThread().isInterrupted());
573 }
574
575 } finally {
576 Thread.interrupted(); // clear interrupt
577
578 latch.countDown();
579 flock.close();
580 }
581
582 // thread should not have throw any exception
583 assertNull(exception.get());
584 }
585
586 /**
587 * Test interrupt of awaitAll.
588 */
589 @ParameterizedTest
590 @MethodSource("factories")
591 void testInterruptAwaitAll2(ThreadFactory factory) {
592 CountDownLatch latch = new CountDownLatch(1);
593 var exception = new AtomicReference<Exception>();
594 Runnable awaitLatch = () -> {
595 try {
596 latch.await();
597 } catch (Exception e) {
598 exception.compareAndSet(null, e);
599 }
600 };
601
602 var flock = ThreadFlock.open(null);
603 try {
604 Thread thread = factory.newThread(awaitLatch);
605 flock.start(thread);
606
607 scheduleInterrupt(Thread.currentThread(), Duration.ofMillis(500));
608 try {
609 flock.awaitAll();
610 fail("awaitAll did not throw");
611 } catch (InterruptedException e) {
612 // interrupt status should be clear
613 assertFalse(Thread.currentThread().isInterrupted());
614 }
615
616 scheduleInterrupt(Thread.currentThread(), Duration.ofMillis(500));
617 try {
618 flock.awaitAll(Duration.ofSeconds(30));
619 fail("awaitAll did not throw");
620 } catch (TimeoutException e) {
621 fail("TimeoutException not expected");
622 } catch (InterruptedException e) {
623 // interrupt status should be clear
624 assertFalse(Thread.currentThread().isInterrupted());
625 }
626
627 } finally {
628 Thread.interrupted(); // clear interrupt
629
630 latch.countDown();
631 flock.close();
632 }
633
634 // thread should not have throw any exception
635 assertNull(exception.get());
636 }
637
638 /**
639 * Test awaitAll after close.
640 */
641 @Test
642 void testAwaitAfterClose() throws Exception {
643 var flock = ThreadFlock.open(null);
644 flock.close();
645 assertTrue(flock.awaitAll());
646 assertTrue(flock.awaitAll(Duration.ofSeconds(1)));
647 }
648
649 /**
650 * Test awaitAll is flock confined.
651 */
652 @ParameterizedTest
653 @MethodSource("factories")
654 void testAwaitAllConfined(ThreadFactory factory) throws Exception {
655 try (var flock = ThreadFlock.open(null)) {
656 // thread in flock
657 testAwaitAllConfined(flock, task -> {
658 Thread thread = factory.newThread(task);
659 return flock.start(thread);
660 });
661
662 // thread not in flock
663 testAwaitAllConfined(flock, task -> {
664 Thread thread = factory.newThread(task);
665 thread.start();
666 return thread;
667 });
668 }
669 }
670
671 /**
672 * Test that a thread created with the given factory cannot call awaitAll.
673 */
674 private void testAwaitAllConfined(ThreadFlock flock,
675 Function<Runnable, Thread> factory) throws Exception {
676 var exception = new AtomicReference<Exception>();
677 Thread thread = factory.apply(() -> {
678 try {
679 flock.awaitAll();
680 flock.awaitAll(Duration.ofMillis(1));
681 } catch (Exception e) {
682 exception.set(e);
683 }
684 });
685 thread.join();
686 Throwable cause = exception.get();
687 assertTrue(cause instanceof WrongThreadException);
688 }
689
690 /**
691 * Test awaitAll with the wakeup permit.
692 */
693 @ParameterizedTest
694 @MethodSource("factories")
695 void testWakeupAwaitAll1(ThreadFactory factory) throws Exception {
696 try (var flock = ThreadFlock.open(null)) {
697 CountDownLatch latch = new CountDownLatch(1);
698 var exception = new AtomicReference<Exception>();
699 Runnable task = () -> {
700 try {
701 latch.await();
702 } catch (Exception e) {
703 exception.compareAndSet(null, e);
704 }
705 };
706 Thread thread = factory.newThread(task);
707 flock.start(thread);
708
709 // invoke awaitAll with permit
710 try {
711 flock.wakeup();
712 assertFalse(flock.awaitAll());
713 } finally {
714 latch.countDown();
715 }
716 }
717 }
718
719 /**
720 * Schedule a thread to wakeup the owner waiting in awaitAll.
721 */
722 @ParameterizedTest
723 @MethodSource("factories")
724 void testWakeupAwaitAll2(ThreadFactory factory) throws Exception {
725 try (var flock = ThreadFlock.open(null)) {
726 CountDownLatch latch = new CountDownLatch(1);
727 var exception = new AtomicReference<Exception>();
728 Runnable task = () -> {
729 try {
730 latch.await();
731 } catch (Exception e) {
732 exception.compareAndSet(null, e);
733 }
734 };
735 Thread thread1 = factory.newThread(task);
736 flock.start(thread1);
737
738 // schedule thread to invoke wakeup
739 Thread thread2 = factory.newThread(() -> {
740 try { Thread.sleep(Duration.ofMillis(500)); } catch (Exception e) { }
741 flock.wakeup();
742 });
743 flock.start(thread2);
744
745 try {
746 assertFalse(flock.awaitAll());
747 } finally {
748 latch.countDown();
749 }
750 }
751 }
752
753 /**
754 * Test wakeup is flock confined.
755 */
756 @ParameterizedTest
757 @MethodSource("factories")
758 void testWakeupConfined(ThreadFactory factory) throws Exception {
759 try (var flock = ThreadFlock.open(null)) {
760 // thread in flock
761 testWakeupConfined(flock, task -> {
762 Thread thread = factory.newThread(task);
763 return flock.start(thread);
764 });
765
766 // thread not in flock
767 testWakeupConfined(flock, task -> {
768 Thread thread = factory.newThread(task);
769 thread.start();
770 return thread;
771 });
772 }
773 }
774
775 /**
776 * Test that a thread created with the given factory cannot wakeup the
777 * given flock.
778 */
779 private void testWakeupConfined(ThreadFlock flock,
780 Function<Runnable, Thread> factory) throws Exception {
781 var exception = new AtomicReference<Exception>();
782 Thread thread = factory.apply(() -> {
783 try {
784 flock.wakeup();
785 } catch (Exception e) {
786 exception.set(e);
787 }
788 });
789 thread.join();
790 Throwable cause = exception.get();
791 if (flock.containsThread(thread)) {
792 assertNull(cause);
793 } else {
794 assertTrue(cause instanceof WrongThreadException);
795 }
796 }
797
798 /**
799 * Test close with no threads running.
800 */
801 @Test
802 void testCloseWithNoThreads() {
803 var flock = ThreadFlock.open(null);
804 flock.close();
805 assertTrue(flock.isClosed());
806 assertTrue(flock.threads().count() == 0);
807 }
808
809 /**
810 * Test close with threads running.
811 */
812 @ParameterizedTest
813 @MethodSource("factories")
814 void testCloseWithThreads(ThreadFactory factory) {
815 var exception = new AtomicReference<Exception>();
816 Runnable sleepTask = () -> {
817 try {
818 Thread.sleep(Duration.ofMillis(50));
819 } catch (Exception e) {
820 exception.set(e);
821 }
822 };
823 var flock = ThreadFlock.open(null);
824 try {
825 Thread thread = factory.newThread(sleepTask);
826 flock.start(thread);
827 } finally {
828 flock.close();
829 }
830 assertTrue(flock.isClosed());
831 assertTrue(flock.threads().count() == 0);
832 assertNull(exception.get()); // no exception thrown
833 }
834
835 /**
836 * Test close after flock is closed.
837 */
838 @Test
839 void testCloseAfterClose() {
840 var flock = ThreadFlock.open(null);
841 flock.close();
842 assertTrue(flock.isClosed());
843 flock.close();
844 assertTrue(flock.isClosed());
845 }
846
847 /**
848 * Test close is owner confined.
849 */
850 @ParameterizedTest
851 @MethodSource("factories")
852 void testCloseConfined(ThreadFactory factory) throws Exception {
853 try (var flock = ThreadFlock.open(null)) {
854 // thread in flock
855 testCloseConfined(flock, task -> {
856 Thread thread = factory.newThread(task);
857 return flock.start(thread);
858 });
859
860 // thread not in flock
861 testCloseConfined(flock, task -> {
862 Thread thread = factory.newThread(task);
863 thread.start();
864 return thread;
865 });
866 }
867 }
868
869 /**
870 * Test that a thread created with the given factory cannot close the
871 * given flock.
872 */
873 private void testCloseConfined(ThreadFlock flock,
874 Function<Runnable, Thread> factory) throws Exception {
875 var exception = new AtomicReference<Exception>();
876 Thread thread = factory.apply(() -> {
877 try {
878 flock.close();
879 } catch (Exception e) {
880 exception.set(e);
881 }
882 });
883 thread.join();
884 Throwable cause = exception.get();
885 assertTrue(cause instanceof WrongThreadException);
886 }
887
888 /**
889 * Test close with interrupt status set, should not interrupt threads.
890 */
891 @ParameterizedTest
892 @MethodSource("factories")
893 void testInterruptClose1(ThreadFactory factory) {
894 var exception = new AtomicReference<Exception>();
895 Runnable sleepTask = () -> {
896 try {
897 Thread.sleep(Duration.ofSeconds(1));
898 } catch (Exception e) {
899 exception.set(e);
900 }
901 };
902 try (var flock = ThreadFlock.open(null)) {
903 Thread thread = factory.newThread(sleepTask);
904 flock.start(thread);
905 Thread.currentThread().interrupt();
906 } finally {
907 assertTrue(Thread.interrupted()); // clear interrupt
908 }
909 assertNull(exception.get());
910 }
911
912 /**
913 * Test interrupt thread block in close.
914 */
915 @ParameterizedTest
916 @MethodSource("factories")
917 void testInterruptClose2(ThreadFactory factory) {
918 var exception = new AtomicReference<Exception>();
919 Runnable sleepTask = () -> {
920 try {
921 Thread.sleep(Duration.ofSeconds(5));
922 } catch (Exception e) {
923 exception.set(e);
924 }
925 };
926 try (var flock = ThreadFlock.open(null)) {
927 Thread thread = factory.newThread(sleepTask);
928 flock.start(thread);
929 scheduleInterrupt(Thread.currentThread(), Duration.ofMillis(500));
930 } finally {
931 assertTrue(Thread.interrupted()); // clear interrupt
932 }
933 assertNull(exception.get());
934 }
935
936 /**
937 * Test shutdown is confined to threads in the flock.
938 */
939 @ParameterizedTest
940 @MethodSource("factories")
941 void testShutdownConfined(ThreadFactory factory) throws Exception {
942 try (var flock = ThreadFlock.open(null)) {
943 // thread in flock
944 testShutdownConfined(flock, task -> {
945 Thread thread = factory.newThread(task);
946 return flock.start(thread);
947 });
948
949 // thread in flock
950 try (var flock2 = ThreadFlock.open(null)) {
951 testShutdownConfined(flock, task -> {
952 Thread thread = factory.newThread(task);
953 return flock2.start(thread);
954 });
955 }
956
957 // thread not contained in flock
958 testShutdownConfined(flock, task -> {
959 Thread thread = factory.newThread(task);
960 thread.start();
961 return thread;
962 });
963 }
964 }
965
966 /**
967 * Test that a thread created with the given factory cannot shut down the
968 * given flock.
969 */
970 private void testShutdownConfined(ThreadFlock flock,
971 Function<Runnable, Thread> factory) throws Exception {
972 var exception = new AtomicReference<Exception>();
973 Thread thread = factory.apply(() -> {
974 try {
975 flock.shutdown();
976 } catch (Exception e) {
977 exception.set(e);
978 }
979 });
980 thread.join();
981 Throwable cause = exception.get();
982 if (flock.containsThread(thread)) {
983 assertNull(cause);
984 } else {
985 assertTrue(cause instanceof WrongThreadException);
986 }
987 }
988
989 /**
990 * Test that closing an enclosing thread flock closes a nested thread flocks.
991 */
992 @Test
993 void testStructureViolation() {
994 try (var flock1 = ThreadFlock.open("flock1")) {
995 try (var flock2 = ThreadFlock.open("flock2")) {
996 try {
997 flock1.close();
998 fail("close did not throw");
999 } catch (RuntimeException e) {
1000 assertTrue(e.toString().contains("Structure"));
1001 }
1002 assertTrue(flock1.isClosed());
1003 assertTrue(flock2.isClosed());
1004 }
1005 }
1006 }
1007
1008 /**
1009 * Test Thread exiting with an open flock. The exiting thread should close the flock.
1010 */
1011 @ParameterizedTest
1012 @MethodSource("factories")
1013 void testThreadExitWithOpenFlock(ThreadFactory factory) throws Exception {
1014 var flockRef = new AtomicReference<ThreadFlock>();
1015 var childRef = new AtomicReference<Thread>();
1016
1017 Thread thread = factory.newThread(() -> {
1018 Thread.dumpStack();
1019
1020 var flock = ThreadFlock.open(null);
1021 Thread child = factory.newThread(() -> {
1022 try {
1023 Thread.sleep(Duration.ofSeconds(2));
1024 } catch (InterruptedException e) { }
1025 });
1026 flock.start(child);
1027 flockRef.set(flock);
1028 childRef.set(child);
1029 });
1030 thread.start();
1031 thread.join();
1032
1033 // flock should be closed and the child thread should have terminated
1034 ThreadFlock flock = flockRef.get();
1035 Thread child = childRef.get();
1036 assertTrue(flock.isClosed() && child.join(Duration.ofMillis(500)));
1037 }
1038
1039 /**
1040 * Test toString includes the flock name.
1041 */
1042 @Test
1043 void testToString() {
1044 try (var flock = ThreadFlock.open("xxxx")) {
1045 assertTrue(flock.toString().contains("xxx"));
1046 }
1047 }
1048
1049 /**
1050 * Test for NullPointerException.
1051 */
1052 @Test
1053 void testNulls() {
1054 try (var flock = ThreadFlock.open(null)) {
1055 assertThrows(NullPointerException.class, () -> flock.start(null));
1056 assertThrows(NullPointerException.class, () -> flock.awaitAll(null));
1057 assertThrows(NullPointerException.class, () -> flock.containsThread(null));
1058 }
1059 }
1060
1061 /**
1062 * Schedules a thread to be interrupted after the given delay.
1063 */
1064 private void scheduleInterrupt(Thread thread, Duration delay) {
1065 long millis = delay.toMillis();
1066 scheduler.schedule(thread::interrupt, millis, TimeUnit.MILLISECONDS);
1067 }
1068
1069 /**
1070 * Returns the current time in milliseconds.
1071 */
1072 private static long millisTime() {
1073 long now = System.nanoTime();
1074 return TimeUnit.MILLISECONDS.convert(now, TimeUnit.NANOSECONDS);
1075 }
1076
1077 /**
1078 * Check the duration of a task
1079 * @param start start time, in milliseconds
1080 * @param min minimum expected duration, in milliseconds
1081 * @param max maximum expected duration, in milliseconds
1082 * @return the duration (now - start), in milliseconds
1083 */
1084 private static long checkDuration(long start, long min, long max) {
1085 long duration = millisTime() - start;
1086 assertTrue(duration >= min,
1087 "Duration " + duration + "ms, expected >= " + min + "ms");
1088 assertTrue(duration <= max,
1089 "Duration " + duration + "ms, expected <= " + max + "ms");
1090 return duration;
1091 }
1092 }