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/licenses/publicdomain |
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* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
* Pat Fisher, Mike Judd. |
7 |
*/ |
8 |
|
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import junit.framework.*; |
10 |
import java.util.*; |
11 |
import java.util.concurrent.*; |
12 |
import java.io.*; |
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|
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public class SemaphoreTest extends JSR166TestCase { |
15 |
public static void main(String[] args) { |
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junit.textui.TestRunner.run (suite()); |
17 |
} |
18 |
public static Test suite() { |
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return new TestSuite(SemaphoreTest.class); |
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} |
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|
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/** |
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* Subclass to expose protected methods |
24 |
*/ |
25 |
static class PublicSemaphore extends Semaphore { |
26 |
PublicSemaphore(int p, boolean f) { super(p, f); } |
27 |
public Collection<Thread> getQueuedThreads() { |
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return super.getQueuedThreads(); |
29 |
} |
30 |
public void reducePermits(int p) { |
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super.reducePermits(p); |
32 |
} |
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} |
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|
35 |
/** |
36 |
* A runnable calling acquire |
37 |
*/ |
38 |
class InterruptibleLockRunnable implements Runnable { |
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final Semaphore lock; |
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InterruptibleLockRunnable(Semaphore l) { lock = l; } |
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public void run() { |
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try { |
43 |
lock.acquire(); |
44 |
} catch(InterruptedException success){} |
45 |
} |
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} |
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|
48 |
|
49 |
/** |
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* A runnable calling acquire that expects to be |
51 |
* interrupted |
52 |
*/ |
53 |
class InterruptedLockRunnable implements Runnable { |
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final Semaphore lock; |
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InterruptedLockRunnable(Semaphore l) { lock = l; } |
56 |
public void run() { |
57 |
try { |
58 |
lock.acquire(); |
59 |
threadShouldThrow(); |
60 |
} catch(InterruptedException success){} |
61 |
} |
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} |
63 |
|
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/** |
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* Zero, negative, and positive initial values are allowed in constructor |
66 |
*/ |
67 |
public void testConstructor() { |
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Semaphore s0 = new Semaphore(0, false); |
69 |
assertEquals(0, s0.availablePermits()); |
70 |
assertFalse(s0.isFair()); |
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Semaphore s1 = new Semaphore(-1, false); |
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assertEquals(-1, s1.availablePermits()); |
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Semaphore s2 = new Semaphore(-1, false); |
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assertEquals(-1, s2.availablePermits()); |
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} |
76 |
|
77 |
/** |
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* tryAcquire succeeds when sufficent permits, else fails |
79 |
*/ |
80 |
public void testTryAcquireInSameThread() { |
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Semaphore s = new Semaphore(2, false); |
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assertEquals(2, s.availablePermits()); |
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assertTrue(s.tryAcquire()); |
84 |
assertTrue(s.tryAcquire()); |
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assertEquals(0, s.availablePermits()); |
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assertFalse(s.tryAcquire()); |
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} |
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|
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/** |
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* Acquire and release of semaphore succeed if initially available |
91 |
*/ |
92 |
public void testAcquireReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
94 |
try { |
95 |
s.acquire(); |
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s.release(); |
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s.acquire(); |
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s.release(); |
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s.acquire(); |
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s.release(); |
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s.acquire(); |
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s.release(); |
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s.acquire(); |
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s.release(); |
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assertEquals(1, s.availablePermits()); |
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} catch( InterruptedException e){ |
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unexpectedException(); |
108 |
} |
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} |
110 |
|
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/** |
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* Uninterruptible acquire and release of semaphore succeed if |
113 |
* initially available |
114 |
*/ |
115 |
public void testAcquireUninterruptiblyReleaseInSameThread() { |
116 |
Semaphore s = new Semaphore(1, false); |
117 |
try { |
118 |
s.acquireUninterruptibly(); |
119 |
s.release(); |
120 |
s.acquireUninterruptibly(); |
121 |
s.release(); |
122 |
s.acquireUninterruptibly(); |
123 |
s.release(); |
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s.acquireUninterruptibly(); |
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s.release(); |
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s.acquireUninterruptibly(); |
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s.release(); |
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assertEquals(1, s.availablePermits()); |
129 |
} finally { |
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} |
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} |
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|
133 |
/** |
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* Timed Acquire and release of semaphore succeed if |
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* initially available |
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*/ |
137 |
public void testTimedAcquireReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
139 |
try { |
140 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
141 |
s.release(); |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
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assertEquals(1, s.availablePermits()); |
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} catch( InterruptedException e){ |
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unexpectedException(); |
153 |
} |
154 |
} |
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|
156 |
/** |
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* A release in one thread enables an acquire in another thread |
158 |
*/ |
159 |
public void testAcquireReleaseInDifferentThreads() { |
160 |
final Semaphore s = new Semaphore(0, false); |
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Thread t = new Thread(new Runnable() { |
162 |
public void run() { |
163 |
try { |
164 |
s.acquire(); |
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s.release(); |
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s.release(); |
167 |
s.acquire(); |
168 |
} catch(InterruptedException ie){ |
169 |
threadUnexpectedException(); |
170 |
} |
171 |
} |
172 |
}); |
173 |
try { |
174 |
t.start(); |
175 |
Thread.sleep(SHORT_DELAY_MS); |
176 |
s.release(); |
177 |
s.release(); |
178 |
s.acquire(); |
179 |
s.acquire(); |
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s.release(); |
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t.join(); |
182 |
} catch( InterruptedException e){ |
183 |
unexpectedException(); |
184 |
} |
185 |
} |
186 |
|
187 |
/** |
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* A release in one thread enables an uninterruptible acquire in another thread |
189 |
*/ |
190 |
public void testUninterruptibleAcquireReleaseInDifferentThreads() { |
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final Semaphore s = new Semaphore(0, false); |
192 |
Thread t = new Thread(new Runnable() { |
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public void run() { |
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s.acquireUninterruptibly(); |
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s.release(); |
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s.release(); |
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s.acquireUninterruptibly(); |
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} |
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}); |
200 |
try { |
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t.start(); |
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Thread.sleep(SHORT_DELAY_MS); |
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s.release(); |
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s.release(); |
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s.acquireUninterruptibly(); |
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s.acquireUninterruptibly(); |
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s.release(); |
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t.join(); |
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} catch( InterruptedException e){ |
210 |
unexpectedException(); |
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} |
212 |
} |
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|
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|
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/** |
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* A release in one thread enables a timed acquire in another thread |
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*/ |
218 |
public void testTimedAcquireReleaseInDifferentThreads() { |
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final Semaphore s = new Semaphore(1, false); |
220 |
Thread t = new Thread(new Runnable() { |
221 |
public void run() { |
222 |
try { |
223 |
s.release(); |
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threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
225 |
s.release(); |
226 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
227 |
|
228 |
} catch(InterruptedException ie){ |
229 |
threadUnexpectedException(); |
230 |
} |
231 |
} |
232 |
}); |
233 |
try { |
234 |
t.start(); |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
236 |
s.release(); |
237 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
238 |
s.release(); |
239 |
s.release(); |
240 |
t.join(); |
241 |
} catch( InterruptedException e){ |
242 |
unexpectedException(); |
243 |
} |
244 |
} |
245 |
|
246 |
/** |
247 |
* A waiting acquire blocks interruptibly |
248 |
*/ |
249 |
public void testAcquire_InterruptedException() { |
250 |
final Semaphore s = new Semaphore(0, false); |
251 |
Thread t = new Thread(new Runnable() { |
252 |
public void run() { |
253 |
try { |
254 |
s.acquire(); |
255 |
threadShouldThrow(); |
256 |
} catch(InterruptedException success){} |
257 |
} |
258 |
}); |
259 |
t.start(); |
260 |
try { |
261 |
Thread.sleep(SHORT_DELAY_MS); |
262 |
t.interrupt(); |
263 |
t.join(); |
264 |
} catch(InterruptedException e){ |
265 |
unexpectedException(); |
266 |
} |
267 |
} |
268 |
|
269 |
/** |
270 |
* A waiting timed acquire blocks interruptibly |
271 |
*/ |
272 |
public void testTryAcquire_InterruptedException() { |
273 |
final Semaphore s = new Semaphore(0, false); |
274 |
Thread t = new Thread(new Runnable() { |
275 |
public void run() { |
276 |
try { |
277 |
s.tryAcquire(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
278 |
threadShouldThrow(); |
279 |
} catch(InterruptedException success){ |
280 |
} |
281 |
} |
282 |
}); |
283 |
t.start(); |
284 |
try { |
285 |
Thread.sleep(SHORT_DELAY_MS); |
286 |
t.interrupt(); |
287 |
t.join(); |
288 |
} catch(InterruptedException e){ |
289 |
unexpectedException(); |
290 |
} |
291 |
} |
292 |
|
293 |
/** |
294 |
* hasQueuedThreads reports whether there are waiting threads |
295 |
*/ |
296 |
public void testHasQueuedThreads() { |
297 |
final Semaphore lock = new Semaphore(1, false); |
298 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
299 |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
300 |
try { |
301 |
assertFalse(lock.hasQueuedThreads()); |
302 |
lock.acquireUninterruptibly(); |
303 |
t1.start(); |
304 |
Thread.sleep(SHORT_DELAY_MS); |
305 |
assertTrue(lock.hasQueuedThreads()); |
306 |
t2.start(); |
307 |
Thread.sleep(SHORT_DELAY_MS); |
308 |
assertTrue(lock.hasQueuedThreads()); |
309 |
t1.interrupt(); |
310 |
Thread.sleep(SHORT_DELAY_MS); |
311 |
assertTrue(lock.hasQueuedThreads()); |
312 |
lock.release(); |
313 |
Thread.sleep(SHORT_DELAY_MS); |
314 |
assertFalse(lock.hasQueuedThreads()); |
315 |
t1.join(); |
316 |
t2.join(); |
317 |
} catch(Exception e){ |
318 |
unexpectedException(); |
319 |
} |
320 |
} |
321 |
|
322 |
/** |
323 |
* getQueueLength reports number of waiting threads |
324 |
*/ |
325 |
public void testGetQueueLength() { |
326 |
final Semaphore lock = new Semaphore(1, false); |
327 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
328 |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
329 |
try { |
330 |
assertEquals(0, lock.getQueueLength()); |
331 |
lock.acquireUninterruptibly(); |
332 |
t1.start(); |
333 |
Thread.sleep(SHORT_DELAY_MS); |
334 |
assertEquals(1, lock.getQueueLength()); |
335 |
t2.start(); |
336 |
Thread.sleep(SHORT_DELAY_MS); |
337 |
assertEquals(2, lock.getQueueLength()); |
338 |
t1.interrupt(); |
339 |
Thread.sleep(SHORT_DELAY_MS); |
340 |
assertEquals(1, lock.getQueueLength()); |
341 |
lock.release(); |
342 |
Thread.sleep(SHORT_DELAY_MS); |
343 |
assertEquals(0, lock.getQueueLength()); |
344 |
t1.join(); |
345 |
t2.join(); |
346 |
} catch(Exception e){ |
347 |
unexpectedException(); |
348 |
} |
349 |
} |
350 |
|
351 |
/** |
352 |
* getQueuedThreads includes waiting threads |
353 |
*/ |
354 |
public void testGetQueuedThreads() { |
355 |
final PublicSemaphore lock = new PublicSemaphore(1, false); |
356 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
357 |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
358 |
try { |
359 |
assertTrue(lock.getQueuedThreads().isEmpty()); |
360 |
lock.acquireUninterruptibly(); |
361 |
assertTrue(lock.getQueuedThreads().isEmpty()); |
362 |
t1.start(); |
363 |
Thread.sleep(SHORT_DELAY_MS); |
364 |
assertTrue(lock.getQueuedThreads().contains(t1)); |
365 |
t2.start(); |
366 |
Thread.sleep(SHORT_DELAY_MS); |
367 |
assertTrue(lock.getQueuedThreads().contains(t1)); |
368 |
assertTrue(lock.getQueuedThreads().contains(t2)); |
369 |
t1.interrupt(); |
370 |
Thread.sleep(SHORT_DELAY_MS); |
371 |
assertFalse(lock.getQueuedThreads().contains(t1)); |
372 |
assertTrue(lock.getQueuedThreads().contains(t2)); |
373 |
lock.release(); |
374 |
Thread.sleep(SHORT_DELAY_MS); |
375 |
assertTrue(lock.getQueuedThreads().isEmpty()); |
376 |
t1.join(); |
377 |
t2.join(); |
378 |
} catch(Exception e){ |
379 |
unexpectedException(); |
380 |
} |
381 |
} |
382 |
|
383 |
|
384 |
/** |
385 |
* reducePermits reduces number of permits |
386 |
*/ |
387 |
public void testReducePermits() { |
388 |
PublicSemaphore s = new PublicSemaphore(10, false); |
389 |
assertEquals(10, s.availablePermits()); |
390 |
s.reducePermits(1); |
391 |
assertEquals(9, s.availablePermits()); |
392 |
s.reducePermits(10); |
393 |
assertEquals(-1, s.availablePermits()); |
394 |
} |
395 |
|
396 |
/** |
397 |
* a deserialized serialized semaphore has same number of permits |
398 |
*/ |
399 |
public void testSerialization() { |
400 |
Semaphore l = new Semaphore(3, false); |
401 |
try { |
402 |
l.acquire(); |
403 |
l.release(); |
404 |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
405 |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
406 |
out.writeObject(l); |
407 |
out.close(); |
408 |
|
409 |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
410 |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
411 |
Semaphore r = (Semaphore) in.readObject(); |
412 |
assertEquals(3, r.availablePermits()); |
413 |
assertFalse(r.isFair()); |
414 |
r.acquire(); |
415 |
r.release(); |
416 |
} catch(Exception e){ |
417 |
unexpectedException(); |
418 |
} |
419 |
} |
420 |
|
421 |
|
422 |
/** |
423 |
* Zero, negative, and positive initial values are allowed in constructor |
424 |
*/ |
425 |
public void testConstructor_fair() { |
426 |
Semaphore s0 = new Semaphore(0, true); |
427 |
assertEquals(0, s0.availablePermits()); |
428 |
assertTrue(s0.isFair()); |
429 |
Semaphore s1 = new Semaphore(-1, true); |
430 |
assertEquals(-1, s1.availablePermits()); |
431 |
Semaphore s2 = new Semaphore(-1, true); |
432 |
assertEquals(-1, s2.availablePermits()); |
433 |
} |
434 |
|
435 |
/** |
436 |
* tryAcquire succeeds when sufficent permits, else fails |
437 |
*/ |
438 |
public void testTryAcquireInSameThread_fair() { |
439 |
Semaphore s = new Semaphore(2, true); |
440 |
assertEquals(2, s.availablePermits()); |
441 |
assertTrue(s.tryAcquire()); |
442 |
assertTrue(s.tryAcquire()); |
443 |
assertEquals(0, s.availablePermits()); |
444 |
assertFalse(s.tryAcquire()); |
445 |
} |
446 |
|
447 |
/** |
448 |
* tryAcquire(n) succeeds when sufficent permits, else fails |
449 |
*/ |
450 |
public void testTryAcquireNInSameThread_fair() { |
451 |
Semaphore s = new Semaphore(2, true); |
452 |
assertEquals(2, s.availablePermits()); |
453 |
assertTrue(s.tryAcquire(2)); |
454 |
assertEquals(0, s.availablePermits()); |
455 |
assertFalse(s.tryAcquire()); |
456 |
} |
457 |
|
458 |
/** |
459 |
* Acquire and release of semaphore succeed if initially available |
460 |
*/ |
461 |
public void testAcquireReleaseInSameThread_fair() { |
462 |
Semaphore s = new Semaphore(1, true); |
463 |
try { |
464 |
s.acquire(); |
465 |
s.release(); |
466 |
s.acquire(); |
467 |
s.release(); |
468 |
s.acquire(); |
469 |
s.release(); |
470 |
s.acquire(); |
471 |
s.release(); |
472 |
s.acquire(); |
473 |
s.release(); |
474 |
assertEquals(1, s.availablePermits()); |
475 |
} catch( InterruptedException e){ |
476 |
unexpectedException(); |
477 |
} |
478 |
} |
479 |
|
480 |
/** |
481 |
* Acquire(n) and release(n) of semaphore succeed if initially available |
482 |
*/ |
483 |
public void testAcquireReleaseNInSameThread_fair() { |
484 |
Semaphore s = new Semaphore(1, true); |
485 |
try { |
486 |
s.release(1); |
487 |
s.acquire(1); |
488 |
s.release(2); |
489 |
s.acquire(2); |
490 |
s.release(3); |
491 |
s.acquire(3); |
492 |
s.release(4); |
493 |
s.acquire(4); |
494 |
s.release(5); |
495 |
s.acquire(5); |
496 |
assertEquals(1, s.availablePermits()); |
497 |
} catch( InterruptedException e){ |
498 |
unexpectedException(); |
499 |
} |
500 |
} |
501 |
|
502 |
/** |
503 |
* Acquire(n) and release(n) of semaphore succeed if initially available |
504 |
*/ |
505 |
public void testAcquireUninterruptiblyReleaseNInSameThread_fair() { |
506 |
Semaphore s = new Semaphore(1, true); |
507 |
try { |
508 |
s.release(1); |
509 |
s.acquireUninterruptibly(1); |
510 |
s.release(2); |
511 |
s.acquireUninterruptibly(2); |
512 |
s.release(3); |
513 |
s.acquireUninterruptibly(3); |
514 |
s.release(4); |
515 |
s.acquireUninterruptibly(4); |
516 |
s.release(5); |
517 |
s.acquireUninterruptibly(5); |
518 |
assertEquals(1, s.availablePermits()); |
519 |
} finally { |
520 |
} |
521 |
} |
522 |
|
523 |
/** |
524 |
* release(n) in one thread enables timed acquire(n) in another thread |
525 |
*/ |
526 |
public void testTimedAcquireReleaseNInSameThread_fair() { |
527 |
Semaphore s = new Semaphore(1, true); |
528 |
try { |
529 |
s.release(1); |
530 |
assertTrue(s.tryAcquire(1, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
531 |
s.release(2); |
532 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
533 |
s.release(3); |
534 |
assertTrue(s.tryAcquire(3, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
535 |
s.release(4); |
536 |
assertTrue(s.tryAcquire(4, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
537 |
s.release(5); |
538 |
assertTrue(s.tryAcquire(5, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
539 |
assertEquals(1, s.availablePermits()); |
540 |
} catch( InterruptedException e){ |
541 |
unexpectedException(); |
542 |
} |
543 |
} |
544 |
|
545 |
/** |
546 |
* release in one thread enables timed acquire in another thread |
547 |
*/ |
548 |
public void testTimedAcquireReleaseInSameThread_fair() { |
549 |
Semaphore s = new Semaphore(1, true); |
550 |
try { |
551 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
552 |
s.release(); |
553 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
554 |
s.release(); |
555 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
556 |
s.release(); |
557 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
558 |
s.release(); |
559 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
560 |
s.release(); |
561 |
assertEquals(1, s.availablePermits()); |
562 |
} catch( InterruptedException e){ |
563 |
unexpectedException(); |
564 |
} |
565 |
} |
566 |
|
567 |
/** |
568 |
* A release in one thread enables an acquire in another thread |
569 |
*/ |
570 |
public void testAcquireReleaseInDifferentThreads_fair() { |
571 |
final Semaphore s = new Semaphore(0, true); |
572 |
Thread t = new Thread(new Runnable() { |
573 |
public void run() { |
574 |
try { |
575 |
s.acquire(); |
576 |
s.acquire(); |
577 |
s.acquire(); |
578 |
s.acquire(); |
579 |
} catch(InterruptedException ie){ |
580 |
threadUnexpectedException(); |
581 |
} |
582 |
} |
583 |
}); |
584 |
try { |
585 |
t.start(); |
586 |
Thread.sleep(SHORT_DELAY_MS); |
587 |
s.release(); |
588 |
s.release(); |
589 |
s.release(); |
590 |
s.release(); |
591 |
s.release(); |
592 |
s.release(); |
593 |
t.join(); |
594 |
assertEquals(2, s.availablePermits()); |
595 |
} catch( InterruptedException e){ |
596 |
unexpectedException(); |
597 |
} |
598 |
} |
599 |
|
600 |
/** |
601 |
* release(n) in one thread enables acquire(n) in another thread |
602 |
*/ |
603 |
public void testAcquireReleaseNInDifferentThreads_fair() { |
604 |
final Semaphore s = new Semaphore(0, true); |
605 |
Thread t = new Thread(new Runnable() { |
606 |
public void run() { |
607 |
try { |
608 |
s.acquire(2); |
609 |
s.acquire(2); |
610 |
s.release(4); |
611 |
} catch(InterruptedException ie){ |
612 |
threadUnexpectedException(); |
613 |
} |
614 |
} |
615 |
}); |
616 |
try { |
617 |
t.start(); |
618 |
Thread.sleep(SHORT_DELAY_MS); |
619 |
s.release(6); |
620 |
s.acquire(2); |
621 |
s.acquire(2); |
622 |
s.release(2); |
623 |
t.join(); |
624 |
} catch( InterruptedException e){ |
625 |
unexpectedException(); |
626 |
} |
627 |
} |
628 |
|
629 |
|
630 |
|
631 |
/** |
632 |
* release in one thread enables timed acquire in another thread |
633 |
*/ |
634 |
public void testTimedAcquireReleaseInDifferentThreads_fair() { |
635 |
final Semaphore s = new Semaphore(1, true); |
636 |
Thread t = new Thread(new Runnable() { |
637 |
public void run() { |
638 |
try { |
639 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
640 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
641 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
642 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
643 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
644 |
|
645 |
} catch(InterruptedException ie){ |
646 |
threadUnexpectedException(); |
647 |
} |
648 |
} |
649 |
}); |
650 |
t.start(); |
651 |
try { |
652 |
s.release(); |
653 |
s.release(); |
654 |
s.release(); |
655 |
s.release(); |
656 |
s.release(); |
657 |
t.join(); |
658 |
} catch( InterruptedException e){ |
659 |
unexpectedException(); |
660 |
} |
661 |
} |
662 |
|
663 |
/** |
664 |
* release(n) in one thread enables timed acquire(n) in another thread |
665 |
*/ |
666 |
public void testTimedAcquireReleaseNInDifferentThreads_fair() { |
667 |
final Semaphore s = new Semaphore(2, true); |
668 |
Thread t = new Thread(new Runnable() { |
669 |
public void run() { |
670 |
try { |
671 |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
672 |
s.release(2); |
673 |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
674 |
s.release(2); |
675 |
} catch(InterruptedException ie){ |
676 |
threadUnexpectedException(); |
677 |
} |
678 |
} |
679 |
}); |
680 |
t.start(); |
681 |
try { |
682 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
683 |
s.release(2); |
684 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
685 |
s.release(2); |
686 |
t.join(); |
687 |
} catch( InterruptedException e){ |
688 |
unexpectedException(); |
689 |
} |
690 |
} |
691 |
|
692 |
/** |
693 |
* A waiting acquire blocks interruptibly |
694 |
*/ |
695 |
public void testAcquire_InterruptedException_fair() { |
696 |
final Semaphore s = new Semaphore(0, true); |
697 |
Thread t = new Thread(new Runnable() { |
698 |
public void run() { |
699 |
try { |
700 |
s.acquire(); |
701 |
threadShouldThrow(); |
702 |
} catch(InterruptedException success){} |
703 |
} |
704 |
}); |
705 |
t.start(); |
706 |
try { |
707 |
Thread.sleep(SHORT_DELAY_MS); |
708 |
t.interrupt(); |
709 |
t.join(); |
710 |
} catch(InterruptedException e){ |
711 |
unexpectedException(); |
712 |
} |
713 |
} |
714 |
|
715 |
/** |
716 |
* A waiting acquire(n) blocks interruptibly |
717 |
*/ |
718 |
public void testAcquireN_InterruptedException_fair() { |
719 |
final Semaphore s = new Semaphore(2, true); |
720 |
Thread t = new Thread(new Runnable() { |
721 |
public void run() { |
722 |
try { |
723 |
s.acquire(3); |
724 |
threadShouldThrow(); |
725 |
} catch(InterruptedException success){} |
726 |
} |
727 |
}); |
728 |
t.start(); |
729 |
try { |
730 |
Thread.sleep(SHORT_DELAY_MS); |
731 |
t.interrupt(); |
732 |
t.join(); |
733 |
} catch(InterruptedException e){ |
734 |
unexpectedException(); |
735 |
} |
736 |
} |
737 |
|
738 |
/** |
739 |
* A waiting tryAcquire blocks interruptibly |
740 |
*/ |
741 |
public void testTryAcquire_InterruptedException_fair() { |
742 |
final Semaphore s = new Semaphore(0, true); |
743 |
Thread t = new Thread(new Runnable() { |
744 |
public void run() { |
745 |
try { |
746 |
s.tryAcquire(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
747 |
threadShouldThrow(); |
748 |
} catch(InterruptedException success){ |
749 |
} |
750 |
} |
751 |
}); |
752 |
t.start(); |
753 |
try { |
754 |
Thread.sleep(SHORT_DELAY_MS); |
755 |
t.interrupt(); |
756 |
t.join(); |
757 |
} catch(InterruptedException e){ |
758 |
unexpectedException(); |
759 |
} |
760 |
} |
761 |
|
762 |
/** |
763 |
* A waiting tryAcquire(n) blocks interruptibly |
764 |
*/ |
765 |
public void testTryAcquireN_InterruptedException_fair() { |
766 |
final Semaphore s = new Semaphore(1, true); |
767 |
Thread t = new Thread(new Runnable() { |
768 |
public void run() { |
769 |
try { |
770 |
s.tryAcquire(4, MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
771 |
threadShouldThrow(); |
772 |
} catch(InterruptedException success){ |
773 |
} |
774 |
} |
775 |
}); |
776 |
t.start(); |
777 |
try { |
778 |
Thread.sleep(SHORT_DELAY_MS); |
779 |
t.interrupt(); |
780 |
t.join(); |
781 |
} catch(InterruptedException e){ |
782 |
unexpectedException(); |
783 |
} |
784 |
} |
785 |
|
786 |
/** |
787 |
* getQueueLength reports number of waiting threads |
788 |
*/ |
789 |
public void testGetQueueLength_fair() { |
790 |
final Semaphore lock = new Semaphore(1, true); |
791 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
792 |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
793 |
try { |
794 |
assertEquals(0, lock.getQueueLength()); |
795 |
lock.acquireUninterruptibly(); |
796 |
t1.start(); |
797 |
Thread.sleep(SHORT_DELAY_MS); |
798 |
assertEquals(1, lock.getQueueLength()); |
799 |
t2.start(); |
800 |
Thread.sleep(SHORT_DELAY_MS); |
801 |
assertEquals(2, lock.getQueueLength()); |
802 |
t1.interrupt(); |
803 |
Thread.sleep(SHORT_DELAY_MS); |
804 |
assertEquals(1, lock.getQueueLength()); |
805 |
lock.release(); |
806 |
Thread.sleep(SHORT_DELAY_MS); |
807 |
assertEquals(0, lock.getQueueLength()); |
808 |
t1.join(); |
809 |
t2.join(); |
810 |
} catch(Exception e){ |
811 |
unexpectedException(); |
812 |
} |
813 |
} |
814 |
|
815 |
|
816 |
/** |
817 |
* a deserialized serialized semaphore has same number of permits |
818 |
*/ |
819 |
public void testSerialization_fair() { |
820 |
Semaphore l = new Semaphore(3, true); |
821 |
|
822 |
try { |
823 |
l.acquire(); |
824 |
l.release(); |
825 |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
826 |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
827 |
out.writeObject(l); |
828 |
out.close(); |
829 |
|
830 |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
831 |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
832 |
Semaphore r = (Semaphore) in.readObject(); |
833 |
assertEquals(3, r.availablePermits()); |
834 |
assertTrue(r.isFair()); |
835 |
r.acquire(); |
836 |
r.release(); |
837 |
} catch(Exception e){ |
838 |
unexpectedException(); |
839 |
} |
840 |
} |
841 |
|
842 |
|
843 |
} |