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 |
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* http://creativecommons.org/licenses/publicdomain |
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* Other contributors include Andrew Wright, Jeffrey Hayes, |
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* Pat Fisher, Mike Judd. |
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*/ |
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|
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import junit.framework.*; |
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import java.util.*; |
11 |
import java.util.concurrent.*; |
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import java.io.*; |
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|
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public class SemaphoreTest extends JSR166TestCase { |
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public static void main(String[] args) { |
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junit.textui.TestRunner.run (suite()); |
17 |
} |
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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 |
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*/ |
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static class PublicSemaphore extends Semaphore { |
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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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|
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/** |
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* 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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|
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|
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/** |
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* A runnable calling acquire that expects to be |
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* interrupted |
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*/ |
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class InterruptedLockRunnable implements Runnable { |
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final Semaphore lock; |
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InterruptedLockRunnable(Semaphore l) { lock = l; } |
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public void run() { |
57 |
try { |
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lock.acquire(); |
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threadShouldThrow(); |
60 |
} catch(InterruptedException success){} |
61 |
} |
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} |
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|
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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); |
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assertEquals(0, s0.availablePermits()); |
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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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} |
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|
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/** |
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* tryAcquire succeeds when sufficient permits, else fails |
79 |
*/ |
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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()); |
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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 |
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*/ |
92 |
public void testAcquireReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
94 |
try { |
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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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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(); |
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} |
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} |
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|
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/** |
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* Uninterruptible acquire and release of semaphore succeed if |
113 |
* initially available |
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*/ |
115 |
public void testAcquireUninterruptiblyReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
117 |
try { |
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s.acquireUninterruptibly(); |
119 |
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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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()); |
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} finally { |
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} |
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} |
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|
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/** |
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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 { |
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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(); |
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} |
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} |
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|
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/** |
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* A release in one thread enables an acquire in another thread |
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*/ |
159 |
public void testAcquireReleaseInDifferentThreads() { |
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final Semaphore s = new Semaphore(0, false); |
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Thread t = new Thread(new Runnable() { |
162 |
public void run() { |
163 |
try { |
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s.acquire(); |
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s.release(); |
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s.release(); |
167 |
s.acquire(); |
168 |
} catch(InterruptedException ie){ |
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threadUnexpectedException(); |
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} |
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} |
172 |
}); |
173 |
try { |
174 |
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.acquire(); |
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s.acquire(); |
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s.release(); |
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t.join(); |
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} catch( InterruptedException e){ |
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unexpectedException(); |
184 |
} |
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} |
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|
187 |
/** |
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* A release in one thread enables an uninterruptible acquire in another thread |
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*/ |
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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}); |
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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){ |
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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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*/ |
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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 { |
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s.release(); |
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threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
225 |
s.release(); |
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threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
227 |
|
228 |
} catch(InterruptedException ie){ |
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threadUnexpectedException(); |
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} |
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} |
232 |
}); |
233 |
try { |
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t.start(); |
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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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s.release(); |
240 |
t.join(); |
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} catch( InterruptedException e){ |
242 |
unexpectedException(); |
243 |
} |
244 |
} |
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|
246 |
/** |
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* A waiting acquire blocks interruptibly |
248 |
*/ |
249 |
public void testAcquire_InterruptedException() { |
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final Semaphore s = new Semaphore(0, false); |
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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 |
|
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/** |
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* 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 |
* drainPermits reports and removes given number of permits |
385 |
*/ |
386 |
public void testDrainPermits() { |
387 |
Semaphore s = new Semaphore(0, false); |
388 |
assertEquals(0, s.availablePermits()); |
389 |
assertEquals(0, s.drainPermits()); |
390 |
s.release(10); |
391 |
assertEquals(10, s.availablePermits()); |
392 |
assertEquals(10, s.drainPermits()); |
393 |
assertEquals(0, s.availablePermits()); |
394 |
assertEquals(0, s.drainPermits()); |
395 |
} |
396 |
|
397 |
/** |
398 |
* reducePermits reduces number of permits |
399 |
*/ |
400 |
public void testReducePermits() { |
401 |
PublicSemaphore s = new PublicSemaphore(10, false); |
402 |
assertEquals(10, s.availablePermits()); |
403 |
s.reducePermits(1); |
404 |
assertEquals(9, s.availablePermits()); |
405 |
s.reducePermits(10); |
406 |
assertEquals(-1, s.availablePermits()); |
407 |
} |
408 |
|
409 |
/** |
410 |
* a deserialized serialized semaphore has same number of permits |
411 |
*/ |
412 |
public void testSerialization() { |
413 |
Semaphore l = new Semaphore(3, false); |
414 |
try { |
415 |
l.acquire(); |
416 |
l.release(); |
417 |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
418 |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
419 |
out.writeObject(l); |
420 |
out.close(); |
421 |
|
422 |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
423 |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
424 |
Semaphore r = (Semaphore) in.readObject(); |
425 |
assertEquals(3, r.availablePermits()); |
426 |
assertFalse(r.isFair()); |
427 |
r.acquire(); |
428 |
r.release(); |
429 |
} catch(Exception e){ |
430 |
unexpectedException(); |
431 |
} |
432 |
} |
433 |
|
434 |
|
435 |
/** |
436 |
* Zero, negative, and positive initial values are allowed in constructor |
437 |
*/ |
438 |
public void testConstructor_fair() { |
439 |
Semaphore s0 = new Semaphore(0, true); |
440 |
assertEquals(0, s0.availablePermits()); |
441 |
assertTrue(s0.isFair()); |
442 |
Semaphore s1 = new Semaphore(-1, true); |
443 |
assertEquals(-1, s1.availablePermits()); |
444 |
Semaphore s2 = new Semaphore(-1, true); |
445 |
assertEquals(-1, s2.availablePermits()); |
446 |
} |
447 |
|
448 |
/** |
449 |
* tryAcquire succeeds when sufficient permits, else fails |
450 |
*/ |
451 |
public void testTryAcquireInSameThread_fair() { |
452 |
Semaphore s = new Semaphore(2, true); |
453 |
assertEquals(2, s.availablePermits()); |
454 |
assertTrue(s.tryAcquire()); |
455 |
assertTrue(s.tryAcquire()); |
456 |
assertEquals(0, s.availablePermits()); |
457 |
assertFalse(s.tryAcquire()); |
458 |
} |
459 |
|
460 |
/** |
461 |
* tryAcquire(n) succeeds when sufficient permits, else fails |
462 |
*/ |
463 |
public void testTryAcquireNInSameThread_fair() { |
464 |
Semaphore s = new Semaphore(2, true); |
465 |
assertEquals(2, s.availablePermits()); |
466 |
assertTrue(s.tryAcquire(2)); |
467 |
assertEquals(0, s.availablePermits()); |
468 |
assertFalse(s.tryAcquire()); |
469 |
} |
470 |
|
471 |
/** |
472 |
* Acquire and release of semaphore succeed if initially available |
473 |
*/ |
474 |
public void testAcquireReleaseInSameThread_fair() { |
475 |
Semaphore s = new Semaphore(1, true); |
476 |
try { |
477 |
s.acquire(); |
478 |
s.release(); |
479 |
s.acquire(); |
480 |
s.release(); |
481 |
s.acquire(); |
482 |
s.release(); |
483 |
s.acquire(); |
484 |
s.release(); |
485 |
s.acquire(); |
486 |
s.release(); |
487 |
assertEquals(1, s.availablePermits()); |
488 |
} catch( InterruptedException e){ |
489 |
unexpectedException(); |
490 |
} |
491 |
} |
492 |
|
493 |
/** |
494 |
* Acquire(n) and release(n) of semaphore succeed if initially available |
495 |
*/ |
496 |
public void testAcquireReleaseNInSameThread_fair() { |
497 |
Semaphore s = new Semaphore(1, true); |
498 |
try { |
499 |
s.release(1); |
500 |
s.acquire(1); |
501 |
s.release(2); |
502 |
s.acquire(2); |
503 |
s.release(3); |
504 |
s.acquire(3); |
505 |
s.release(4); |
506 |
s.acquire(4); |
507 |
s.release(5); |
508 |
s.acquire(5); |
509 |
assertEquals(1, s.availablePermits()); |
510 |
} catch( InterruptedException e){ |
511 |
unexpectedException(); |
512 |
} |
513 |
} |
514 |
|
515 |
/** |
516 |
* Acquire(n) and release(n) of semaphore succeed if initially available |
517 |
*/ |
518 |
public void testAcquireUninterruptiblyReleaseNInSameThread_fair() { |
519 |
Semaphore s = new Semaphore(1, true); |
520 |
try { |
521 |
s.release(1); |
522 |
s.acquireUninterruptibly(1); |
523 |
s.release(2); |
524 |
s.acquireUninterruptibly(2); |
525 |
s.release(3); |
526 |
s.acquireUninterruptibly(3); |
527 |
s.release(4); |
528 |
s.acquireUninterruptibly(4); |
529 |
s.release(5); |
530 |
s.acquireUninterruptibly(5); |
531 |
assertEquals(1, s.availablePermits()); |
532 |
} finally { |
533 |
} |
534 |
} |
535 |
|
536 |
/** |
537 |
* release(n) in one thread enables timed acquire(n) in another thread |
538 |
*/ |
539 |
public void testTimedAcquireReleaseNInSameThread_fair() { |
540 |
Semaphore s = new Semaphore(1, true); |
541 |
try { |
542 |
s.release(1); |
543 |
assertTrue(s.tryAcquire(1, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
544 |
s.release(2); |
545 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
546 |
s.release(3); |
547 |
assertTrue(s.tryAcquire(3, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
548 |
s.release(4); |
549 |
assertTrue(s.tryAcquire(4, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
550 |
s.release(5); |
551 |
assertTrue(s.tryAcquire(5, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
552 |
assertEquals(1, s.availablePermits()); |
553 |
} catch( InterruptedException e){ |
554 |
unexpectedException(); |
555 |
} |
556 |
} |
557 |
|
558 |
/** |
559 |
* release in one thread enables timed acquire in another thread |
560 |
*/ |
561 |
public void testTimedAcquireReleaseInSameThread_fair() { |
562 |
Semaphore s = new Semaphore(1, true); |
563 |
try { |
564 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
565 |
s.release(); |
566 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
567 |
s.release(); |
568 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
569 |
s.release(); |
570 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
571 |
s.release(); |
572 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
573 |
s.release(); |
574 |
assertEquals(1, s.availablePermits()); |
575 |
} catch( InterruptedException e){ |
576 |
unexpectedException(); |
577 |
} |
578 |
} |
579 |
|
580 |
/** |
581 |
* A release in one thread enables an acquire in another thread |
582 |
*/ |
583 |
public void testAcquireReleaseInDifferentThreads_fair() { |
584 |
final Semaphore s = new Semaphore(0, true); |
585 |
Thread t = new Thread(new Runnable() { |
586 |
public void run() { |
587 |
try { |
588 |
s.acquire(); |
589 |
s.acquire(); |
590 |
s.acquire(); |
591 |
s.acquire(); |
592 |
} catch(InterruptedException ie){ |
593 |
threadUnexpectedException(); |
594 |
} |
595 |
} |
596 |
}); |
597 |
try { |
598 |
t.start(); |
599 |
Thread.sleep(SHORT_DELAY_MS); |
600 |
s.release(); |
601 |
s.release(); |
602 |
s.release(); |
603 |
s.release(); |
604 |
s.release(); |
605 |
s.release(); |
606 |
t.join(); |
607 |
assertEquals(2, s.availablePermits()); |
608 |
} catch( InterruptedException e){ |
609 |
unexpectedException(); |
610 |
} |
611 |
} |
612 |
|
613 |
/** |
614 |
* release(n) in one thread enables acquire(n) in another thread |
615 |
*/ |
616 |
public void testAcquireReleaseNInDifferentThreads_fair() { |
617 |
final Semaphore s = new Semaphore(0, true); |
618 |
Thread t = new Thread(new Runnable() { |
619 |
public void run() { |
620 |
try { |
621 |
s.acquire(); |
622 |
s.release(2); |
623 |
s.acquire(); |
624 |
} catch(InterruptedException ie){ |
625 |
threadUnexpectedException(); |
626 |
} |
627 |
} |
628 |
}); |
629 |
try { |
630 |
t.start(); |
631 |
Thread.sleep(SHORT_DELAY_MS); |
632 |
s.release(2); |
633 |
s.acquire(2); |
634 |
s.release(1); |
635 |
t.join(); |
636 |
} catch( InterruptedException e){ |
637 |
unexpectedException(); |
638 |
} |
639 |
} |
640 |
|
641 |
/** |
642 |
* release(n) in one thread enables acquire(n) in another thread |
643 |
*/ |
644 |
public void testAcquireReleaseNInDifferentThreads_fair2() { |
645 |
final Semaphore s = new Semaphore(0, true); |
646 |
Thread t = new Thread(new Runnable() { |
647 |
public void run() { |
648 |
try { |
649 |
s.acquire(2); |
650 |
s.acquire(2); |
651 |
s.release(4); |
652 |
} catch(InterruptedException ie){ |
653 |
threadUnexpectedException(); |
654 |
} |
655 |
} |
656 |
}); |
657 |
try { |
658 |
t.start(); |
659 |
Thread.sleep(SHORT_DELAY_MS); |
660 |
s.release(6); |
661 |
s.acquire(2); |
662 |
s.acquire(2); |
663 |
s.release(2); |
664 |
t.join(); |
665 |
} catch( InterruptedException e){ |
666 |
unexpectedException(); |
667 |
} |
668 |
} |
669 |
|
670 |
|
671 |
|
672 |
|
673 |
|
674 |
/** |
675 |
* release in one thread enables timed acquire in another thread |
676 |
*/ |
677 |
public void testTimedAcquireReleaseInDifferentThreads_fair() { |
678 |
final Semaphore s = new Semaphore(1, true); |
679 |
Thread t = new Thread(new Runnable() { |
680 |
public void run() { |
681 |
try { |
682 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
683 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
684 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
685 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
686 |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
687 |
|
688 |
} catch(InterruptedException ie){ |
689 |
threadUnexpectedException(); |
690 |
} |
691 |
} |
692 |
}); |
693 |
t.start(); |
694 |
try { |
695 |
s.release(); |
696 |
s.release(); |
697 |
s.release(); |
698 |
s.release(); |
699 |
s.release(); |
700 |
t.join(); |
701 |
} catch( InterruptedException e){ |
702 |
unexpectedException(); |
703 |
} |
704 |
} |
705 |
|
706 |
/** |
707 |
* release(n) in one thread enables timed acquire(n) in another thread |
708 |
*/ |
709 |
public void testTimedAcquireReleaseNInDifferentThreads_fair() { |
710 |
final Semaphore s = new Semaphore(2, true); |
711 |
Thread t = new Thread(new Runnable() { |
712 |
public void run() { |
713 |
try { |
714 |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
715 |
s.release(2); |
716 |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
717 |
s.release(2); |
718 |
} catch(InterruptedException ie){ |
719 |
threadUnexpectedException(); |
720 |
} |
721 |
} |
722 |
}); |
723 |
t.start(); |
724 |
try { |
725 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
726 |
s.release(2); |
727 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
728 |
s.release(2); |
729 |
t.join(); |
730 |
} catch( InterruptedException e){ |
731 |
unexpectedException(); |
732 |
} |
733 |
} |
734 |
|
735 |
/** |
736 |
* A waiting acquire blocks interruptibly |
737 |
*/ |
738 |
public void testAcquire_InterruptedException_fair() { |
739 |
final Semaphore s = new Semaphore(0, true); |
740 |
Thread t = new Thread(new Runnable() { |
741 |
public void run() { |
742 |
try { |
743 |
s.acquire(); |
744 |
threadShouldThrow(); |
745 |
} catch(InterruptedException success){} |
746 |
} |
747 |
}); |
748 |
t.start(); |
749 |
try { |
750 |
Thread.sleep(SHORT_DELAY_MS); |
751 |
t.interrupt(); |
752 |
t.join(); |
753 |
} catch(InterruptedException e){ |
754 |
unexpectedException(); |
755 |
} |
756 |
} |
757 |
|
758 |
/** |
759 |
* A waiting acquire(n) blocks interruptibly |
760 |
*/ |
761 |
public void testAcquireN_InterruptedException_fair() { |
762 |
final Semaphore s = new Semaphore(2, true); |
763 |
Thread t = new Thread(new Runnable() { |
764 |
public void run() { |
765 |
try { |
766 |
s.acquire(3); |
767 |
threadShouldThrow(); |
768 |
} catch(InterruptedException success){} |
769 |
} |
770 |
}); |
771 |
t.start(); |
772 |
try { |
773 |
Thread.sleep(SHORT_DELAY_MS); |
774 |
t.interrupt(); |
775 |
t.join(); |
776 |
} catch(InterruptedException e){ |
777 |
unexpectedException(); |
778 |
} |
779 |
} |
780 |
|
781 |
/** |
782 |
* A waiting tryAcquire blocks interruptibly |
783 |
*/ |
784 |
public void testTryAcquire_InterruptedException_fair() { |
785 |
final Semaphore s = new Semaphore(0, true); |
786 |
Thread t = new Thread(new Runnable() { |
787 |
public void run() { |
788 |
try { |
789 |
s.tryAcquire(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
790 |
threadShouldThrow(); |
791 |
} catch(InterruptedException success){ |
792 |
} |
793 |
} |
794 |
}); |
795 |
t.start(); |
796 |
try { |
797 |
Thread.sleep(SHORT_DELAY_MS); |
798 |
t.interrupt(); |
799 |
t.join(); |
800 |
} catch(InterruptedException e){ |
801 |
unexpectedException(); |
802 |
} |
803 |
} |
804 |
|
805 |
/** |
806 |
* A waiting tryAcquire(n) blocks interruptibly |
807 |
*/ |
808 |
public void testTryAcquireN_InterruptedException_fair() { |
809 |
final Semaphore s = new Semaphore(1, true); |
810 |
Thread t = new Thread(new Runnable() { |
811 |
public void run() { |
812 |
try { |
813 |
s.tryAcquire(4, MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
814 |
threadShouldThrow(); |
815 |
} catch(InterruptedException success){ |
816 |
} |
817 |
} |
818 |
}); |
819 |
t.start(); |
820 |
try { |
821 |
Thread.sleep(SHORT_DELAY_MS); |
822 |
t.interrupt(); |
823 |
t.join(); |
824 |
} catch(InterruptedException e){ |
825 |
unexpectedException(); |
826 |
} |
827 |
} |
828 |
|
829 |
/** |
830 |
* getQueueLength reports number of waiting threads |
831 |
*/ |
832 |
public void testGetQueueLength_fair() { |
833 |
final Semaphore lock = new Semaphore(1, true); |
834 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
835 |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
836 |
try { |
837 |
assertEquals(0, lock.getQueueLength()); |
838 |
lock.acquireUninterruptibly(); |
839 |
t1.start(); |
840 |
Thread.sleep(SHORT_DELAY_MS); |
841 |
assertEquals(1, lock.getQueueLength()); |
842 |
t2.start(); |
843 |
Thread.sleep(SHORT_DELAY_MS); |
844 |
assertEquals(2, lock.getQueueLength()); |
845 |
t1.interrupt(); |
846 |
Thread.sleep(SHORT_DELAY_MS); |
847 |
assertEquals(1, lock.getQueueLength()); |
848 |
lock.release(); |
849 |
Thread.sleep(SHORT_DELAY_MS); |
850 |
assertEquals(0, lock.getQueueLength()); |
851 |
t1.join(); |
852 |
t2.join(); |
853 |
} catch(Exception e){ |
854 |
unexpectedException(); |
855 |
} |
856 |
} |
857 |
|
858 |
|
859 |
/** |
860 |
* a deserialized serialized semaphore has same number of permits |
861 |
*/ |
862 |
public void testSerialization_fair() { |
863 |
Semaphore l = new Semaphore(3, true); |
864 |
|
865 |
try { |
866 |
l.acquire(); |
867 |
l.release(); |
868 |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
869 |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
870 |
out.writeObject(l); |
871 |
out.close(); |
872 |
|
873 |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
874 |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
875 |
Semaphore r = (Semaphore) in.readObject(); |
876 |
assertEquals(3, r.availablePermits()); |
877 |
assertTrue(r.isFair()); |
878 |
r.acquire(); |
879 |
r.release(); |
880 |
} catch(Exception e){ |
881 |
unexpectedException(); |
882 |
} |
883 |
} |
884 |
|
885 |
|
886 |
} |