1 |
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/* |
2 |
< |
* Written by members of JCP JSR-166 Expert Group and released to the |
3 |
< |
* public domain. Use, modify, and redistribute this code in any way |
4 |
< |
* without acknowledgement. Other contributors include Andrew Wright, |
5 |
< |
* Jeffrey Hayes, Pat Fischer, Mike Judd. |
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/licenses/publicdomain |
5 |
> |
* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
> |
* Pat Fisher, Mike Judd. |
7 |
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*/ |
8 |
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9 |
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import junit.framework.*; |
20 |
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} |
21 |
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|
22 |
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/** |
23 |
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* Subclass to expose protected methods |
24 |
+ |
*/ |
25 |
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static class PublicSemaphore extends Semaphore { |
26 |
+ |
PublicSemaphore(int p, boolean f) { super(p, f); } |
27 |
+ |
public Collection<Thread> getQueuedThreads() { |
28 |
+ |
return super.getQueuedThreads(); |
29 |
+ |
} |
30 |
+ |
public void reducePermits(int p) { |
31 |
+ |
super.reducePermits(p); |
32 |
+ |
} |
33 |
+ |
} |
34 |
+ |
|
35 |
+ |
/** |
36 |
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* A runnable calling acquire |
37 |
+ |
*/ |
38 |
+ |
class InterruptibleLockRunnable implements Runnable { |
39 |
+ |
final Semaphore lock; |
40 |
+ |
InterruptibleLockRunnable(Semaphore l) { lock = l; } |
41 |
+ |
public void run() { |
42 |
+ |
try { |
43 |
+ |
lock.acquire(); |
44 |
+ |
} catch(InterruptedException success){} |
45 |
+ |
} |
46 |
+ |
} |
47 |
+ |
|
48 |
+ |
|
49 |
+ |
/** |
50 |
+ |
* A runnable calling acquire that expects to be |
51 |
+ |
* interrupted |
52 |
+ |
*/ |
53 |
+ |
class InterruptedLockRunnable implements Runnable { |
54 |
+ |
final Semaphore lock; |
55 |
+ |
InterruptedLockRunnable(Semaphore l) { lock = l; } |
56 |
+ |
public void run() { |
57 |
+ |
try { |
58 |
+ |
lock.acquire(); |
59 |
+ |
threadShouldThrow(); |
60 |
+ |
} catch(InterruptedException success){} |
61 |
+ |
} |
62 |
+ |
} |
63 |
+ |
|
64 |
+ |
/** |
65 |
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* Zero, negative, and positive initial values are allowed in constructor |
66 |
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*/ |
67 |
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public void testConstructor() { |
68 |
+ |
Semaphore s0 = new Semaphore(0, false); |
69 |
+ |
assertEquals(0, s0.availablePermits()); |
70 |
+ |
assertFalse(s0.isFair()); |
71 |
+ |
Semaphore s1 = new Semaphore(-1, false); |
72 |
+ |
assertEquals(-1, s1.availablePermits()); |
73 |
+ |
assertFalse(s1.isFair()); |
74 |
+ |
Semaphore s2 = new Semaphore(-1, false); |
75 |
+ |
assertEquals(-1, s2.availablePermits()); |
76 |
+ |
assertFalse(s2.isFair()); |
77 |
+ |
} |
78 |
+ |
|
79 |
+ |
/** |
80 |
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* Constructor without fairness argument behaves as nonfair |
81 |
+ |
*/ |
82 |
+ |
public void testConstructor2() { |
83 |
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Semaphore s0 = new Semaphore(0); |
84 |
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assertEquals(0, s0.availablePermits()); |
85 |
+ |
assertFalse(s0.isFair()); |
86 |
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Semaphore s1 = new Semaphore(-1); |
87 |
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assertEquals(-1, s1.availablePermits()); |
88 |
+ |
assertFalse(s1.isFair()); |
89 |
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Semaphore s2 = new Semaphore(-1); |
90 |
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assertEquals(-1, s2.availablePermits()); |
91 |
+ |
assertFalse(s2.isFair()); |
92 |
|
} |
93 |
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|
94 |
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/** |
95 |
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* tryAcquire succeeds when sufficent permits, else fails |
95 |
> |
* tryAcquire succeeds when sufficient permits, else fails |
96 |
|
*/ |
97 |
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public void testTryAcquireInSameThread() { |
98 |
< |
Semaphore s = new Semaphore(2); |
98 |
> |
Semaphore s = new Semaphore(2, false); |
99 |
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assertEquals(2, s.availablePermits()); |
100 |
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assertTrue(s.tryAcquire()); |
101 |
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assertTrue(s.tryAcquire()); |
107 |
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* Acquire and release of semaphore succeed if initially available |
108 |
|
*/ |
109 |
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public void testAcquireReleaseInSameThread() { |
110 |
< |
Semaphore s = new Semaphore(1); |
110 |
> |
Semaphore s = new Semaphore(1, false); |
111 |
|
try { |
112 |
|
s.acquire(); |
113 |
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s.release(); |
130 |
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* initially available |
131 |
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*/ |
132 |
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public void testAcquireUninterruptiblyReleaseInSameThread() { |
133 |
< |
Semaphore s = new Semaphore(1); |
133 |
> |
Semaphore s = new Semaphore(1, false); |
134 |
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try { |
135 |
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s.acquireUninterruptibly(); |
136 |
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s.release(); |
152 |
|
* initially available |
153 |
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*/ |
154 |
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public void testTimedAcquireReleaseInSameThread() { |
155 |
< |
Semaphore s = new Semaphore(1); |
155 |
> |
Semaphore s = new Semaphore(1, false); |
156 |
|
try { |
157 |
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
158 |
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s.release(); |
174 |
|
* A release in one thread enables an acquire in another thread |
175 |
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*/ |
176 |
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public void testAcquireReleaseInDifferentThreads() { |
177 |
< |
final Semaphore s = new Semaphore(0); |
177 |
> |
final Semaphore s = new Semaphore(0, false); |
178 |
|
Thread t = new Thread(new Runnable() { |
179 |
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public void run() { |
180 |
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try { |
205 |
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* A release in one thread enables an uninterruptible acquire in another thread |
206 |
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*/ |
207 |
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public void testUninterruptibleAcquireReleaseInDifferentThreads() { |
208 |
< |
final Semaphore s = new Semaphore(0); |
208 |
> |
final Semaphore s = new Semaphore(0, false); |
209 |
|
Thread t = new Thread(new Runnable() { |
210 |
|
public void run() { |
211 |
|
s.acquireUninterruptibly(); |
233 |
|
* A release in one thread enables a timed acquire in another thread |
234 |
|
*/ |
235 |
|
public void testTimedAcquireReleaseInDifferentThreads() { |
236 |
< |
final Semaphore s = new Semaphore(1); |
236 |
> |
final Semaphore s = new Semaphore(1, false); |
237 |
|
Thread t = new Thread(new Runnable() { |
238 |
|
public void run() { |
239 |
|
try { |
264 |
|
* A waiting acquire blocks interruptibly |
265 |
|
*/ |
266 |
|
public void testAcquire_InterruptedException() { |
267 |
< |
final Semaphore s = new Semaphore(0); |
267 |
> |
final Semaphore s = new Semaphore(0, false); |
268 |
|
Thread t = new Thread(new Runnable() { |
269 |
|
public void run() { |
270 |
|
try { |
287 |
|
* A waiting timed acquire blocks interruptibly |
288 |
|
*/ |
289 |
|
public void testTryAcquire_InterruptedException() { |
290 |
< |
final Semaphore s = new Semaphore(0); |
290 |
> |
final Semaphore s = new Semaphore(0, false); |
291 |
|
Thread t = new Thread(new Runnable() { |
292 |
|
public void run() { |
293 |
|
try { |
308 |
|
} |
309 |
|
|
310 |
|
/** |
311 |
+ |
* hasQueuedThreads reports whether there are waiting threads |
312 |
+ |
*/ |
313 |
+ |
public void testHasQueuedThreads() { |
314 |
+ |
final Semaphore lock = new Semaphore(1, false); |
315 |
+ |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
316 |
+ |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
317 |
+ |
try { |
318 |
+ |
assertFalse(lock.hasQueuedThreads()); |
319 |
+ |
lock.acquireUninterruptibly(); |
320 |
+ |
t1.start(); |
321 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
322 |
+ |
assertTrue(lock.hasQueuedThreads()); |
323 |
+ |
t2.start(); |
324 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
325 |
+ |
assertTrue(lock.hasQueuedThreads()); |
326 |
+ |
t1.interrupt(); |
327 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
328 |
+ |
assertTrue(lock.hasQueuedThreads()); |
329 |
+ |
lock.release(); |
330 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
331 |
+ |
assertFalse(lock.hasQueuedThreads()); |
332 |
+ |
t1.join(); |
333 |
+ |
t2.join(); |
334 |
+ |
} catch(Exception e){ |
335 |
+ |
unexpectedException(); |
336 |
+ |
} |
337 |
+ |
} |
338 |
+ |
|
339 |
+ |
/** |
340 |
+ |
* getQueueLength reports number of waiting threads |
341 |
+ |
*/ |
342 |
+ |
public void testGetQueueLength() { |
343 |
+ |
final Semaphore lock = new Semaphore(1, false); |
344 |
+ |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
345 |
+ |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
346 |
+ |
try { |
347 |
+ |
assertEquals(0, lock.getQueueLength()); |
348 |
+ |
lock.acquireUninterruptibly(); |
349 |
+ |
t1.start(); |
350 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
351 |
+ |
assertEquals(1, lock.getQueueLength()); |
352 |
+ |
t2.start(); |
353 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
354 |
+ |
assertEquals(2, lock.getQueueLength()); |
355 |
+ |
t1.interrupt(); |
356 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
357 |
+ |
assertEquals(1, lock.getQueueLength()); |
358 |
+ |
lock.release(); |
359 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
360 |
+ |
assertEquals(0, lock.getQueueLength()); |
361 |
+ |
t1.join(); |
362 |
+ |
t2.join(); |
363 |
+ |
} catch(Exception e){ |
364 |
+ |
unexpectedException(); |
365 |
+ |
} |
366 |
+ |
} |
367 |
+ |
|
368 |
+ |
/** |
369 |
+ |
* getQueuedThreads includes waiting threads |
370 |
+ |
*/ |
371 |
+ |
public void testGetQueuedThreads() { |
372 |
+ |
final PublicSemaphore lock = new PublicSemaphore(1, false); |
373 |
+ |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
374 |
+ |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
375 |
+ |
try { |
376 |
+ |
assertTrue(lock.getQueuedThreads().isEmpty()); |
377 |
+ |
lock.acquireUninterruptibly(); |
378 |
+ |
assertTrue(lock.getQueuedThreads().isEmpty()); |
379 |
+ |
t1.start(); |
380 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
381 |
+ |
assertTrue(lock.getQueuedThreads().contains(t1)); |
382 |
+ |
t2.start(); |
383 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
384 |
+ |
assertTrue(lock.getQueuedThreads().contains(t1)); |
385 |
+ |
assertTrue(lock.getQueuedThreads().contains(t2)); |
386 |
+ |
t1.interrupt(); |
387 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
388 |
+ |
assertFalse(lock.getQueuedThreads().contains(t1)); |
389 |
+ |
assertTrue(lock.getQueuedThreads().contains(t2)); |
390 |
+ |
lock.release(); |
391 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
392 |
+ |
assertTrue(lock.getQueuedThreads().isEmpty()); |
393 |
+ |
t1.join(); |
394 |
+ |
t2.join(); |
395 |
+ |
} catch(Exception e){ |
396 |
+ |
unexpectedException(); |
397 |
+ |
} |
398 |
+ |
} |
399 |
+ |
|
400 |
+ |
/** |
401 |
+ |
* drainPermits reports and removes given number of permits |
402 |
+ |
*/ |
403 |
+ |
public void testDrainPermits() { |
404 |
+ |
Semaphore s = new Semaphore(0, false); |
405 |
+ |
assertEquals(0, s.availablePermits()); |
406 |
+ |
assertEquals(0, s.drainPermits()); |
407 |
+ |
s.release(10); |
408 |
+ |
assertEquals(10, s.availablePermits()); |
409 |
+ |
assertEquals(10, s.drainPermits()); |
410 |
+ |
assertEquals(0, s.availablePermits()); |
411 |
+ |
assertEquals(0, s.drainPermits()); |
412 |
+ |
} |
413 |
+ |
|
414 |
+ |
/** |
415 |
+ |
* reducePermits reduces number of permits |
416 |
+ |
*/ |
417 |
+ |
public void testReducePermits() { |
418 |
+ |
PublicSemaphore s = new PublicSemaphore(10, false); |
419 |
+ |
assertEquals(10, s.availablePermits()); |
420 |
+ |
s.reducePermits(1); |
421 |
+ |
assertEquals(9, s.availablePermits()); |
422 |
+ |
s.reducePermits(10); |
423 |
+ |
assertEquals(-1, s.availablePermits()); |
424 |
+ |
} |
425 |
+ |
|
426 |
+ |
/** |
427 |
|
* a deserialized serialized semaphore has same number of permits |
428 |
|
*/ |
429 |
|
public void testSerialization() { |
430 |
< |
Semaphore l = new Semaphore(3); |
430 |
> |
Semaphore l = new Semaphore(3, false); |
431 |
|
try { |
432 |
|
l.acquire(); |
433 |
|
l.release(); |
440 |
|
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
441 |
|
Semaphore r = (Semaphore) in.readObject(); |
442 |
|
assertEquals(3, r.availablePermits()); |
443 |
+ |
assertFalse(r.isFair()); |
444 |
|
r.acquire(); |
445 |
|
r.release(); |
446 |
|
} catch(Exception e){ |
448 |
|
} |
449 |
|
} |
450 |
|
|
451 |
+ |
|
452 |
+ |
/** |
453 |
+ |
* Zero, negative, and positive initial values are allowed in constructor |
454 |
+ |
*/ |
455 |
+ |
public void testConstructor_fair() { |
456 |
+ |
Semaphore s0 = new Semaphore(0, true); |
457 |
+ |
assertEquals(0, s0.availablePermits()); |
458 |
+ |
assertTrue(s0.isFair()); |
459 |
+ |
Semaphore s1 = new Semaphore(-1, true); |
460 |
+ |
assertEquals(-1, s1.availablePermits()); |
461 |
+ |
Semaphore s2 = new Semaphore(-1, true); |
462 |
+ |
assertEquals(-1, s2.availablePermits()); |
463 |
+ |
} |
464 |
+ |
|
465 |
+ |
/** |
466 |
+ |
* tryAcquire succeeds when sufficient permits, else fails |
467 |
+ |
*/ |
468 |
+ |
public void testTryAcquireInSameThread_fair() { |
469 |
+ |
Semaphore s = new Semaphore(2, true); |
470 |
+ |
assertEquals(2, s.availablePermits()); |
471 |
+ |
assertTrue(s.tryAcquire()); |
472 |
+ |
assertTrue(s.tryAcquire()); |
473 |
+ |
assertEquals(0, s.availablePermits()); |
474 |
+ |
assertFalse(s.tryAcquire()); |
475 |
+ |
} |
476 |
+ |
|
477 |
+ |
/** |
478 |
+ |
* tryAcquire(n) succeeds when sufficient permits, else fails |
479 |
+ |
*/ |
480 |
+ |
public void testTryAcquireNInSameThread_fair() { |
481 |
+ |
Semaphore s = new Semaphore(2, true); |
482 |
+ |
assertEquals(2, s.availablePermits()); |
483 |
+ |
assertTrue(s.tryAcquire(2)); |
484 |
+ |
assertEquals(0, s.availablePermits()); |
485 |
+ |
assertFalse(s.tryAcquire()); |
486 |
+ |
} |
487 |
+ |
|
488 |
+ |
/** |
489 |
+ |
* Acquire and release of semaphore succeed if initially available |
490 |
+ |
*/ |
491 |
+ |
public void testAcquireReleaseInSameThread_fair() { |
492 |
+ |
Semaphore s = new Semaphore(1, true); |
493 |
+ |
try { |
494 |
+ |
s.acquire(); |
495 |
+ |
s.release(); |
496 |
+ |
s.acquire(); |
497 |
+ |
s.release(); |
498 |
+ |
s.acquire(); |
499 |
+ |
s.release(); |
500 |
+ |
s.acquire(); |
501 |
+ |
s.release(); |
502 |
+ |
s.acquire(); |
503 |
+ |
s.release(); |
504 |
+ |
assertEquals(1, s.availablePermits()); |
505 |
+ |
} catch( InterruptedException e){ |
506 |
+ |
unexpectedException(); |
507 |
+ |
} |
508 |
+ |
} |
509 |
+ |
|
510 |
+ |
/** |
511 |
+ |
* Acquire(n) and release(n) of semaphore succeed if initially available |
512 |
+ |
*/ |
513 |
+ |
public void testAcquireReleaseNInSameThread_fair() { |
514 |
+ |
Semaphore s = new Semaphore(1, true); |
515 |
+ |
try { |
516 |
+ |
s.release(1); |
517 |
+ |
s.acquire(1); |
518 |
+ |
s.release(2); |
519 |
+ |
s.acquire(2); |
520 |
+ |
s.release(3); |
521 |
+ |
s.acquire(3); |
522 |
+ |
s.release(4); |
523 |
+ |
s.acquire(4); |
524 |
+ |
s.release(5); |
525 |
+ |
s.acquire(5); |
526 |
+ |
assertEquals(1, s.availablePermits()); |
527 |
+ |
} catch( InterruptedException e){ |
528 |
+ |
unexpectedException(); |
529 |
+ |
} |
530 |
+ |
} |
531 |
+ |
|
532 |
+ |
/** |
533 |
+ |
* Acquire(n) and release(n) of semaphore succeed if initially available |
534 |
+ |
*/ |
535 |
+ |
public void testAcquireUninterruptiblyReleaseNInSameThread_fair() { |
536 |
+ |
Semaphore s = new Semaphore(1, true); |
537 |
+ |
try { |
538 |
+ |
s.release(1); |
539 |
+ |
s.acquireUninterruptibly(1); |
540 |
+ |
s.release(2); |
541 |
+ |
s.acquireUninterruptibly(2); |
542 |
+ |
s.release(3); |
543 |
+ |
s.acquireUninterruptibly(3); |
544 |
+ |
s.release(4); |
545 |
+ |
s.acquireUninterruptibly(4); |
546 |
+ |
s.release(5); |
547 |
+ |
s.acquireUninterruptibly(5); |
548 |
+ |
assertEquals(1, s.availablePermits()); |
549 |
+ |
} finally { |
550 |
+ |
} |
551 |
+ |
} |
552 |
+ |
|
553 |
+ |
/** |
554 |
+ |
* release(n) in one thread enables timed acquire(n) in another thread |
555 |
+ |
*/ |
556 |
+ |
public void testTimedAcquireReleaseNInSameThread_fair() { |
557 |
+ |
Semaphore s = new Semaphore(1, true); |
558 |
+ |
try { |
559 |
+ |
s.release(1); |
560 |
+ |
assertTrue(s.tryAcquire(1, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
561 |
+ |
s.release(2); |
562 |
+ |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
563 |
+ |
s.release(3); |
564 |
+ |
assertTrue(s.tryAcquire(3, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
565 |
+ |
s.release(4); |
566 |
+ |
assertTrue(s.tryAcquire(4, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
567 |
+ |
s.release(5); |
568 |
+ |
assertTrue(s.tryAcquire(5, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
569 |
+ |
assertEquals(1, s.availablePermits()); |
570 |
+ |
} catch( InterruptedException e){ |
571 |
+ |
unexpectedException(); |
572 |
+ |
} |
573 |
+ |
} |
574 |
+ |
|
575 |
+ |
/** |
576 |
+ |
* release in one thread enables timed acquire in another thread |
577 |
+ |
*/ |
578 |
+ |
public void testTimedAcquireReleaseInSameThread_fair() { |
579 |
+ |
Semaphore s = new Semaphore(1, true); |
580 |
+ |
try { |
581 |
+ |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
582 |
+ |
s.release(); |
583 |
+ |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
584 |
+ |
s.release(); |
585 |
+ |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
586 |
+ |
s.release(); |
587 |
+ |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
588 |
+ |
s.release(); |
589 |
+ |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
590 |
+ |
s.release(); |
591 |
+ |
assertEquals(1, s.availablePermits()); |
592 |
+ |
} catch( InterruptedException e){ |
593 |
+ |
unexpectedException(); |
594 |
+ |
} |
595 |
+ |
} |
596 |
+ |
|
597 |
+ |
/** |
598 |
+ |
* A release in one thread enables an acquire in another thread |
599 |
+ |
*/ |
600 |
+ |
public void testAcquireReleaseInDifferentThreads_fair() { |
601 |
+ |
final Semaphore s = new Semaphore(0, true); |
602 |
+ |
Thread t = new Thread(new Runnable() { |
603 |
+ |
public void run() { |
604 |
+ |
try { |
605 |
+ |
s.acquire(); |
606 |
+ |
s.acquire(); |
607 |
+ |
s.acquire(); |
608 |
+ |
s.acquire(); |
609 |
+ |
} catch(InterruptedException ie){ |
610 |
+ |
threadUnexpectedException(); |
611 |
+ |
} |
612 |
+ |
} |
613 |
+ |
}); |
614 |
+ |
try { |
615 |
+ |
t.start(); |
616 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
617 |
+ |
s.release(); |
618 |
+ |
s.release(); |
619 |
+ |
s.release(); |
620 |
+ |
s.release(); |
621 |
+ |
s.release(); |
622 |
+ |
s.release(); |
623 |
+ |
t.join(); |
624 |
+ |
assertEquals(2, s.availablePermits()); |
625 |
+ |
} catch( InterruptedException e){ |
626 |
+ |
unexpectedException(); |
627 |
+ |
} |
628 |
+ |
} |
629 |
+ |
|
630 |
+ |
/** |
631 |
+ |
* release(n) in one thread enables acquire(n) in another thread |
632 |
+ |
*/ |
633 |
+ |
public void testAcquireReleaseNInDifferentThreads_fair() { |
634 |
+ |
final Semaphore s = new Semaphore(0, true); |
635 |
+ |
Thread t = new Thread(new Runnable() { |
636 |
+ |
public void run() { |
637 |
+ |
try { |
638 |
+ |
s.acquire(); |
639 |
+ |
s.release(2); |
640 |
+ |
s.acquire(); |
641 |
+ |
} catch(InterruptedException ie){ |
642 |
+ |
threadUnexpectedException(); |
643 |
+ |
} |
644 |
+ |
} |
645 |
+ |
}); |
646 |
+ |
try { |
647 |
+ |
t.start(); |
648 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
649 |
+ |
s.release(2); |
650 |
+ |
s.acquire(2); |
651 |
+ |
s.release(1); |
652 |
+ |
t.join(); |
653 |
+ |
} catch( InterruptedException e){ |
654 |
+ |
unexpectedException(); |
655 |
+ |
} |
656 |
+ |
} |
657 |
+ |
|
658 |
+ |
/** |
659 |
+ |
* release(n) in one thread enables acquire(n) in another thread |
660 |
+ |
*/ |
661 |
+ |
public void testAcquireReleaseNInDifferentThreads_fair2() { |
662 |
+ |
final Semaphore s = new Semaphore(0, true); |
663 |
+ |
Thread t = new Thread(new Runnable() { |
664 |
+ |
public void run() { |
665 |
+ |
try { |
666 |
+ |
s.acquire(2); |
667 |
+ |
s.acquire(2); |
668 |
+ |
s.release(4); |
669 |
+ |
} catch(InterruptedException ie){ |
670 |
+ |
threadUnexpectedException(); |
671 |
+ |
} |
672 |
+ |
} |
673 |
+ |
}); |
674 |
+ |
try { |
675 |
+ |
t.start(); |
676 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
677 |
+ |
s.release(6); |
678 |
+ |
s.acquire(2); |
679 |
+ |
s.acquire(2); |
680 |
+ |
s.release(2); |
681 |
+ |
t.join(); |
682 |
+ |
} catch( InterruptedException e){ |
683 |
+ |
unexpectedException(); |
684 |
+ |
} |
685 |
+ |
} |
686 |
+ |
|
687 |
+ |
|
688 |
+ |
|
689 |
+ |
|
690 |
+ |
|
691 |
+ |
/** |
692 |
+ |
* release in one thread enables timed acquire in another thread |
693 |
+ |
*/ |
694 |
+ |
public void testTimedAcquireReleaseInDifferentThreads_fair() { |
695 |
+ |
final Semaphore s = new Semaphore(1, true); |
696 |
+ |
Thread t = new Thread(new Runnable() { |
697 |
+ |
public void run() { |
698 |
+ |
try { |
699 |
+ |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
700 |
+ |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
701 |
+ |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
702 |
+ |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
703 |
+ |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
704 |
+ |
|
705 |
+ |
} catch(InterruptedException ie){ |
706 |
+ |
threadUnexpectedException(); |
707 |
+ |
} |
708 |
+ |
} |
709 |
+ |
}); |
710 |
+ |
t.start(); |
711 |
+ |
try { |
712 |
+ |
s.release(); |
713 |
+ |
s.release(); |
714 |
+ |
s.release(); |
715 |
+ |
s.release(); |
716 |
+ |
s.release(); |
717 |
+ |
t.join(); |
718 |
+ |
} catch( InterruptedException e){ |
719 |
+ |
unexpectedException(); |
720 |
+ |
} |
721 |
+ |
} |
722 |
+ |
|
723 |
+ |
/** |
724 |
+ |
* release(n) in one thread enables timed acquire(n) in another thread |
725 |
+ |
*/ |
726 |
+ |
public void testTimedAcquireReleaseNInDifferentThreads_fair() { |
727 |
+ |
final Semaphore s = new Semaphore(2, true); |
728 |
+ |
Thread t = new Thread(new Runnable() { |
729 |
+ |
public void run() { |
730 |
+ |
try { |
731 |
+ |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
732 |
+ |
s.release(2); |
733 |
+ |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
734 |
+ |
s.release(2); |
735 |
+ |
} catch(InterruptedException ie){ |
736 |
+ |
threadUnexpectedException(); |
737 |
+ |
} |
738 |
+ |
} |
739 |
+ |
}); |
740 |
+ |
t.start(); |
741 |
+ |
try { |
742 |
+ |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
743 |
+ |
s.release(2); |
744 |
+ |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
745 |
+ |
s.release(2); |
746 |
+ |
t.join(); |
747 |
+ |
} catch( InterruptedException e){ |
748 |
+ |
unexpectedException(); |
749 |
+ |
} |
750 |
+ |
} |
751 |
+ |
|
752 |
+ |
/** |
753 |
+ |
* A waiting acquire blocks interruptibly |
754 |
+ |
*/ |
755 |
+ |
public void testAcquire_InterruptedException_fair() { |
756 |
+ |
final Semaphore s = new Semaphore(0, true); |
757 |
+ |
Thread t = new Thread(new Runnable() { |
758 |
+ |
public void run() { |
759 |
+ |
try { |
760 |
+ |
s.acquire(); |
761 |
+ |
threadShouldThrow(); |
762 |
+ |
} catch(InterruptedException success){} |
763 |
+ |
} |
764 |
+ |
}); |
765 |
+ |
t.start(); |
766 |
+ |
try { |
767 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
768 |
+ |
t.interrupt(); |
769 |
+ |
t.join(); |
770 |
+ |
} catch(InterruptedException e){ |
771 |
+ |
unexpectedException(); |
772 |
+ |
} |
773 |
+ |
} |
774 |
+ |
|
775 |
+ |
/** |
776 |
+ |
* A waiting acquire(n) blocks interruptibly |
777 |
+ |
*/ |
778 |
+ |
public void testAcquireN_InterruptedException_fair() { |
779 |
+ |
final Semaphore s = new Semaphore(2, true); |
780 |
+ |
Thread t = new Thread(new Runnable() { |
781 |
+ |
public void run() { |
782 |
+ |
try { |
783 |
+ |
s.acquire(3); |
784 |
+ |
threadShouldThrow(); |
785 |
+ |
} catch(InterruptedException success){} |
786 |
+ |
} |
787 |
+ |
}); |
788 |
+ |
t.start(); |
789 |
+ |
try { |
790 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
791 |
+ |
t.interrupt(); |
792 |
+ |
t.join(); |
793 |
+ |
} catch(InterruptedException e){ |
794 |
+ |
unexpectedException(); |
795 |
+ |
} |
796 |
+ |
} |
797 |
+ |
|
798 |
+ |
/** |
799 |
+ |
* A waiting tryAcquire blocks interruptibly |
800 |
+ |
*/ |
801 |
+ |
public void testTryAcquire_InterruptedException_fair() { |
802 |
+ |
final Semaphore s = new Semaphore(0, true); |
803 |
+ |
Thread t = new Thread(new Runnable() { |
804 |
+ |
public void run() { |
805 |
+ |
try { |
806 |
+ |
s.tryAcquire(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
807 |
+ |
threadShouldThrow(); |
808 |
+ |
} catch(InterruptedException success){ |
809 |
+ |
} |
810 |
+ |
} |
811 |
+ |
}); |
812 |
+ |
t.start(); |
813 |
+ |
try { |
814 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
815 |
+ |
t.interrupt(); |
816 |
+ |
t.join(); |
817 |
+ |
} catch(InterruptedException e){ |
818 |
+ |
unexpectedException(); |
819 |
+ |
} |
820 |
+ |
} |
821 |
+ |
|
822 |
+ |
/** |
823 |
+ |
* A waiting tryAcquire(n) blocks interruptibly |
824 |
+ |
*/ |
825 |
+ |
public void testTryAcquireN_InterruptedException_fair() { |
826 |
+ |
final Semaphore s = new Semaphore(1, true); |
827 |
+ |
Thread t = new Thread(new Runnable() { |
828 |
+ |
public void run() { |
829 |
+ |
try { |
830 |
+ |
s.tryAcquire(4, MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
831 |
+ |
threadShouldThrow(); |
832 |
+ |
} catch(InterruptedException success){ |
833 |
+ |
} |
834 |
+ |
} |
835 |
+ |
}); |
836 |
+ |
t.start(); |
837 |
+ |
try { |
838 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
839 |
+ |
t.interrupt(); |
840 |
+ |
t.join(); |
841 |
+ |
} catch(InterruptedException e){ |
842 |
+ |
unexpectedException(); |
843 |
+ |
} |
844 |
+ |
} |
845 |
+ |
|
846 |
+ |
/** |
847 |
+ |
* getQueueLength reports number of waiting threads |
848 |
+ |
*/ |
849 |
+ |
public void testGetQueueLength_fair() { |
850 |
+ |
final Semaphore lock = new Semaphore(1, true); |
851 |
+ |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
852 |
+ |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
853 |
+ |
try { |
854 |
+ |
assertEquals(0, lock.getQueueLength()); |
855 |
+ |
lock.acquireUninterruptibly(); |
856 |
+ |
t1.start(); |
857 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
858 |
+ |
assertEquals(1, lock.getQueueLength()); |
859 |
+ |
t2.start(); |
860 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
861 |
+ |
assertEquals(2, lock.getQueueLength()); |
862 |
+ |
t1.interrupt(); |
863 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
864 |
+ |
assertEquals(1, lock.getQueueLength()); |
865 |
+ |
lock.release(); |
866 |
+ |
Thread.sleep(SHORT_DELAY_MS); |
867 |
+ |
assertEquals(0, lock.getQueueLength()); |
868 |
+ |
t1.join(); |
869 |
+ |
t2.join(); |
870 |
+ |
} catch(Exception e){ |
871 |
+ |
unexpectedException(); |
872 |
+ |
} |
873 |
+ |
} |
874 |
+ |
|
875 |
+ |
|
876 |
+ |
/** |
877 |
+ |
* a deserialized serialized semaphore has same number of permits |
878 |
+ |
*/ |
879 |
+ |
public void testSerialization_fair() { |
880 |
+ |
Semaphore l = new Semaphore(3, true); |
881 |
+ |
|
882 |
+ |
try { |
883 |
+ |
l.acquire(); |
884 |
+ |
l.release(); |
885 |
+ |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
886 |
+ |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
887 |
+ |
out.writeObject(l); |
888 |
+ |
out.close(); |
889 |
+ |
|
890 |
+ |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
891 |
+ |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
892 |
+ |
Semaphore r = (Semaphore) in.readObject(); |
893 |
+ |
assertEquals(3, r.availablePermits()); |
894 |
+ |
assertTrue(r.isFair()); |
895 |
+ |
r.acquire(); |
896 |
+ |
r.release(); |
897 |
+ |
} catch(Exception e){ |
898 |
+ |
unexpectedException(); |
899 |
+ |
} |
900 |
+ |
} |
901 |
+ |
|
902 |
+ |
|
903 |
|
} |