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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* 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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* http://creativecommons.org/publicdomain/zero/1.0/ |
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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.*; |
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import java.util.concurrent.*; |
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import java.io.*; |
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import static java.util.concurrent.TimeUnit.MILLISECONDS; |
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|
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import java.util.Collection; |
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import java.util.concurrent.CountDownLatch; |
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import java.util.concurrent.Semaphore; |
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|
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import junit.framework.AssertionFailedError; |
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import junit.framework.Test; |
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import junit.framework.TestSuite; |
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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()); |
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main(suite(), args); |
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} |
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public static Test suite() { |
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return new TestSuite(SemaphoreTest.class); |
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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); } |
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public Collection<Thread> getQueuedThreads() { |
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return super.getQueuedThreads(); |
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PublicSemaphore(int permits) { super(permits); } |
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PublicSemaphore(int permits, boolean fair) { super(permits, fair); } |
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public Collection<Thread> getQueuedThreads() { |
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return super.getQueuedThreads(); |
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} |
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public boolean hasQueuedThread(Thread t) { |
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return super.getQueuedThreads().contains(t); |
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} |
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public void reducePermits(int p) { |
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super.reducePermits(p); |
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public void reducePermits(int reduction) { |
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super.reducePermits(reduction); |
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} |
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} |
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|
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/** |
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* A runnable calling acquire |
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*/ |
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class InterruptibleLockRunnable implements Runnable { |
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class InterruptibleLockRunnable extends CheckedRunnable { |
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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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InterruptibleLockRunnable(Semaphore s) { lock = s; } |
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public void realRun() { |
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try { |
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lock.acquire(); |
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} catch(InterruptedException success){} |
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} |
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catch (InterruptedException ignored) {} |
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} |
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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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* A runnable calling acquire that expects to be interrupted |
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*/ |
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class InterruptedLockRunnable implements Runnable { |
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class InterruptedLockRunnable extends CheckedInterruptedRunnable { |
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final Semaphore lock; |
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InterruptedLockRunnable(Semaphore l) { lock = l; } |
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public void run() { |
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try { |
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lock.acquire(); |
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threadShouldThrow(); |
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} catch(InterruptedException success){} |
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InterruptedLockRunnable(Semaphore s) { lock = s; } |
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public void realRun() throws InterruptedException { |
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lock.acquire(); |
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} |
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} |
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|
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/** |
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* Spin-waits until s.hasQueuedThread(t) becomes true. |
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*/ |
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void waitForQueuedThread(PublicSemaphore s, Thread t) { |
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long startTime = System.nanoTime(); |
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while (!s.hasQueuedThread(t)) { |
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if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
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throw new AssertionFailedError("timed out"); |
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Thread.yield(); |
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} |
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assertTrue(s.hasQueuedThreads()); |
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assertTrue(t.isAlive()); |
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} |
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|
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/** |
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* Spin-waits until s.hasQueuedThreads() becomes true. |
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*/ |
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void waitForQueuedThreads(Semaphore s) { |
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long startTime = System.nanoTime(); |
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while (!s.hasQueuedThreads()) { |
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if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
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throw new AssertionFailedError("timed out"); |
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Thread.yield(); |
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} |
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} |
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|
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enum AcquireMethod { |
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acquire() { |
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void acquire(Semaphore s) throws InterruptedException { |
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s.acquire(); |
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} |
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}, |
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acquireN() { |
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void acquire(Semaphore s, int permits) throws InterruptedException { |
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s.acquire(permits); |
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} |
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}, |
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acquireUninterruptibly() { |
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void acquire(Semaphore s) { |
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s.acquireUninterruptibly(); |
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} |
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}, |
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acquireUninterruptiblyN() { |
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void acquire(Semaphore s, int permits) { |
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s.acquireUninterruptibly(permits); |
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} |
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}, |
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tryAcquire() { |
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void acquire(Semaphore s) { |
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assertTrue(s.tryAcquire()); |
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} |
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}, |
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tryAcquireN() { |
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void acquire(Semaphore s, int permits) { |
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assertTrue(s.tryAcquire(permits)); |
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} |
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}, |
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tryAcquireTimed() { |
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void acquire(Semaphore s) throws InterruptedException { |
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assertTrue(s.tryAcquire(2 * LONG_DELAY_MS, MILLISECONDS)); |
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} |
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}, |
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tryAcquireTimedN { |
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void acquire(Semaphore s, int permits) throws InterruptedException { |
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assertTrue(s.tryAcquire(permits, 2 * LONG_DELAY_MS, MILLISECONDS)); |
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} |
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}; |
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|
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// Intentionally meta-circular |
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|
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/** Acquires 1 permit. */ |
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void acquire(Semaphore s) throws InterruptedException { |
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acquire(s, 1); |
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} |
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/** Acquires the given number of permits. */ |
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void acquire(Semaphore s, int permits) throws InterruptedException { |
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for (int i = 0; i < permits; i++) |
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acquire(s); |
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} |
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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 |
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*/ |
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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 |
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*/ |
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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 |
91 |
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*/ |
92 |
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public void testAcquireReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
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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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} |
110 |
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|
111 |
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/** |
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* Uninterruptible acquire and release of semaphore succeed if |
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* initially available |
114 |
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*/ |
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public void testAcquireUninterruptiblyReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
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try { |
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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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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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public void testConstructor() { testConstructor(false); } |
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public void testConstructor_fair() { testConstructor(true); } |
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public void testConstructor(boolean fair) { |
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for (int permits : new int[] { -42, -1, 0, 1, 42 }) { |
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Semaphore s = new Semaphore(permits, fair); |
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assertEquals(permits, s.availablePermits()); |
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assertEquals(fair, s.isFair()); |
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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 |
164 |
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* Constructor without fairness argument behaves as nonfair |
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*/ |
166 |
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public void testTimedAcquireReleaseInSameThread() { |
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Semaphore s = new Semaphore(1, false); |
168 |
< |
try { |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
170 |
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s.release(); |
142 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
144 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
146 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
148 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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s.release(); |
150 |
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assertEquals(1, s.availablePermits()); |
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< |
} catch( InterruptedException e){ |
152 |
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unexpectedException(); |
166 |
> |
public void testConstructorDefaultsToNonFair() { |
167 |
> |
for (int permits : new int[] { -42, -1, 0, 1, 42 }) { |
168 |
> |
Semaphore s = new Semaphore(permits); |
169 |
> |
assertEquals(permits, s.availablePermits()); |
170 |
> |
assertFalse(s.isFair()); |
171 |
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} |
172 |
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} |
173 |
|
|
174 |
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/** |
175 |
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* A release in one thread enables an acquire in another thread |
175 |
> |
* tryAcquire succeeds when sufficient permits, else fails |
176 |
|
*/ |
177 |
< |
public void testAcquireReleaseInDifferentThreads() { |
178 |
< |
final Semaphore s = new Semaphore(0, false); |
179 |
< |
Thread t = new Thread(new Runnable() { |
180 |
< |
public void run() { |
181 |
< |
try { |
182 |
< |
s.acquire(); |
183 |
< |
s.release(); |
184 |
< |
s.release(); |
185 |
< |
s.acquire(); |
186 |
< |
} catch(InterruptedException ie){ |
187 |
< |
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(); |
180 |
< |
s.release(); |
181 |
< |
t.join(); |
182 |
< |
} catch( InterruptedException e){ |
183 |
< |
unexpectedException(); |
184 |
< |
} |
177 |
> |
public void testTryAcquireInSameThread() { testTryAcquireInSameThread(false); } |
178 |
> |
public void testTryAcquireInSameThread_fair() { testTryAcquireInSameThread(true); } |
179 |
> |
public void testTryAcquireInSameThread(boolean fair) { |
180 |
> |
Semaphore s = new Semaphore(2, fair); |
181 |
> |
assertEquals(2, s.availablePermits()); |
182 |
> |
assertTrue(s.tryAcquire()); |
183 |
> |
assertTrue(s.tryAcquire()); |
184 |
> |
assertEquals(0, s.availablePermits()); |
185 |
> |
assertFalse(s.tryAcquire()); |
186 |
> |
assertFalse(s.tryAcquire()); |
187 |
> |
assertEquals(0, s.availablePermits()); |
188 |
|
} |
189 |
|
|
190 |
|
/** |
191 |
< |
* A release in one thread enables an uninterruptible acquire in another thread |
191 |
> |
* timed tryAcquire times out |
192 |
|
*/ |
193 |
< |
public void testUninterruptibleAcquireReleaseInDifferentThreads() { |
194 |
< |
final Semaphore s = new Semaphore(0, false); |
195 |
< |
Thread t = new Thread(new Runnable() { |
196 |
< |
public void run() { |
197 |
< |
s.acquireUninterruptibly(); |
198 |
< |
s.release(); |
199 |
< |
s.release(); |
200 |
< |
s.acquireUninterruptibly(); |
201 |
< |
} |
202 |
< |
}); |
203 |
< |
try { |
204 |
< |
t.start(); |
205 |
< |
Thread.sleep(SHORT_DELAY_MS); |
206 |
< |
s.release(); |
207 |
< |
s.release(); |
208 |
< |
s.acquireUninterruptibly(); |
209 |
< |
s.acquireUninterruptibly(); |
210 |
< |
s.release(); |
211 |
< |
t.join(); |
212 |
< |
} catch( InterruptedException e){ |
213 |
< |
unexpectedException(); |
214 |
< |
} |
215 |
< |
} |
193 |
> |
public void testTryAcquire_timeout() { testTryAcquire_timeout(false); } |
194 |
> |
public void testTryAcquire_timeout_fair() { testTryAcquire_timeout(true); } |
195 |
> |
public void testTryAcquire_timeout(boolean fair) { |
196 |
> |
Semaphore s = new Semaphore(0, fair); |
197 |
> |
long startTime = System.nanoTime(); |
198 |
> |
try { assertFalse(s.tryAcquire(timeoutMillis(), MILLISECONDS)); } |
199 |
> |
catch (InterruptedException e) { threadUnexpectedException(e); } |
200 |
> |
assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
201 |
> |
} |
202 |
> |
|
203 |
> |
/** |
204 |
> |
* timed tryAcquire(N) times out |
205 |
> |
*/ |
206 |
> |
public void testTryAcquireN_timeout() { testTryAcquireN_timeout(false); } |
207 |
> |
public void testTryAcquireN_timeout_fair() { testTryAcquireN_timeout(true); } |
208 |
> |
public void testTryAcquireN_timeout(boolean fair) { |
209 |
> |
Semaphore s = new Semaphore(2, fair); |
210 |
> |
long startTime = System.nanoTime(); |
211 |
> |
try { assertFalse(s.tryAcquire(3, timeoutMillis(), MILLISECONDS)); } |
212 |
> |
catch (InterruptedException e) { threadUnexpectedException(e); } |
213 |
> |
assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
214 |
> |
} |
215 |
> |
|
216 |
> |
/** |
217 |
> |
* acquire(), acquire(N), timed tryAcquired, timed tryAcquire(N) |
218 |
> |
* are interruptible |
219 |
> |
*/ |
220 |
> |
public void testInterruptible_acquire() { testInterruptible(false, AcquireMethod.acquire); } |
221 |
> |
public void testInterruptible_acquire_fair() { testInterruptible(true, AcquireMethod.acquire); } |
222 |
> |
public void testInterruptible_acquireN() { testInterruptible(false, AcquireMethod.acquireN); } |
223 |
> |
public void testInterruptible_acquireN_fair() { testInterruptible(true, AcquireMethod.acquireN); } |
224 |
> |
public void testInterruptible_tryAcquireTimed() { testInterruptible(false, AcquireMethod.tryAcquireTimed); } |
225 |
> |
public void testInterruptible_tryAcquireTimed_fair() { testInterruptible(true, AcquireMethod.tryAcquireTimed); } |
226 |
> |
public void testInterruptible_tryAcquireTimedN() { testInterruptible(false, AcquireMethod.tryAcquireTimedN); } |
227 |
> |
public void testInterruptible_tryAcquireTimedN_fair() { testInterruptible(true, AcquireMethod.tryAcquireTimedN); } |
228 |
> |
public void testInterruptible(boolean fair, final AcquireMethod acquirer) { |
229 |
> |
final PublicSemaphore s = new PublicSemaphore(0, fair); |
230 |
> |
final Semaphore pleaseInterrupt = new Semaphore(0, fair); |
231 |
> |
Thread t = newStartedThread(new CheckedRunnable() { |
232 |
> |
public void realRun() { |
233 |
> |
// Interrupt before acquire |
234 |
> |
Thread.currentThread().interrupt(); |
235 |
> |
try { |
236 |
> |
acquirer.acquire(s); |
237 |
> |
shouldThrow(); |
238 |
> |
} catch (InterruptedException success) {} |
239 |
> |
|
240 |
> |
// Interrupt during acquire |
241 |
> |
try { |
242 |
> |
acquirer.acquire(s); |
243 |
> |
shouldThrow(); |
244 |
> |
} catch (InterruptedException success) {} |
245 |
> |
|
246 |
> |
// Interrupt before acquire(N) |
247 |
> |
Thread.currentThread().interrupt(); |
248 |
> |
try { |
249 |
> |
acquirer.acquire(s, 3); |
250 |
> |
shouldThrow(); |
251 |
> |
} catch (InterruptedException success) {} |
252 |
> |
|
253 |
> |
pleaseInterrupt.release(); |
254 |
> |
|
255 |
> |
// Interrupt during acquire(N) |
256 |
> |
try { |
257 |
> |
acquirer.acquire(s, 3); |
258 |
> |
shouldThrow(); |
259 |
> |
} catch (InterruptedException success) {} |
260 |
> |
}}); |
261 |
> |
|
262 |
> |
waitForQueuedThread(s, t); |
263 |
> |
t.interrupt(); |
264 |
> |
await(pleaseInterrupt); |
265 |
> |
waitForQueuedThread(s, t); |
266 |
> |
t.interrupt(); |
267 |
> |
awaitTermination(t); |
268 |
> |
} |
269 |
> |
|
270 |
> |
/** |
271 |
> |
* acquireUninterruptibly(), acquireUninterruptibly(N) are |
272 |
> |
* uninterruptible |
273 |
> |
*/ |
274 |
> |
public void testUninterruptible_acquireUninterruptibly() { testUninterruptible(false, AcquireMethod.acquireUninterruptibly); } |
275 |
> |
public void testUninterruptible_acquireUninterruptibly_fair() { testUninterruptible(true, AcquireMethod.acquireUninterruptibly); } |
276 |
> |
public void testUninterruptible_acquireUninterruptiblyN() { testUninterruptible(false, AcquireMethod.acquireUninterruptiblyN); } |
277 |
> |
public void testUninterruptible_acquireUninterruptiblyN_fair() { testUninterruptible(true, AcquireMethod.acquireUninterruptiblyN); } |
278 |
> |
public void testUninterruptible(boolean fair, final AcquireMethod acquirer) { |
279 |
> |
final PublicSemaphore s = new PublicSemaphore(0, fair); |
280 |
> |
final Semaphore pleaseInterrupt = new Semaphore(-1, fair); |
281 |
> |
|
282 |
> |
Thread t1 = newStartedThread(new CheckedRunnable() { |
283 |
> |
public void realRun() throws InterruptedException { |
284 |
> |
// Interrupt before acquire |
285 |
> |
pleaseInterrupt.release(); |
286 |
> |
Thread.currentThread().interrupt(); |
287 |
> |
acquirer.acquire(s); |
288 |
> |
assertTrue(Thread.interrupted()); |
289 |
> |
}}); |
290 |
> |
|
291 |
> |
Thread t2 = newStartedThread(new CheckedRunnable() { |
292 |
> |
public void realRun() throws InterruptedException { |
293 |
> |
// Interrupt during acquire |
294 |
> |
pleaseInterrupt.release(); |
295 |
> |
acquirer.acquire(s); |
296 |
> |
assertTrue(Thread.interrupted()); |
297 |
> |
}}); |
298 |
> |
|
299 |
> |
await(pleaseInterrupt); |
300 |
> |
waitForQueuedThread(s, t1); |
301 |
> |
waitForQueuedThread(s, t2); |
302 |
> |
t2.interrupt(); |
303 |
|
|
304 |
+ |
assertThreadStaysAlive(t1); |
305 |
+ |
assertTrue(t2.isAlive()); |
306 |
|
|
307 |
< |
/** |
216 |
< |
* A release in one thread enables a timed acquire in another thread |
217 |
< |
*/ |
218 |
< |
public void testTimedAcquireReleaseInDifferentThreads() { |
219 |
< |
final Semaphore s = new Semaphore(1, false); |
220 |
< |
Thread t = new Thread(new Runnable() { |
221 |
< |
public void run() { |
222 |
< |
try { |
223 |
< |
s.release(); |
224 |
< |
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(); |
235 |
< |
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 |
< |
} |
307 |
> |
s.release(2); |
308 |
|
|
309 |
< |
/** |
310 |
< |
* 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 |
< |
} |
309 |
> |
awaitTermination(t1); |
310 |
> |
awaitTermination(t2); |
311 |
|
} |
312 |
|
|
313 |
|
/** |
314 |
|
* hasQueuedThreads reports whether there are waiting threads |
315 |
|
*/ |
316 |
< |
public void testHasQueuedThreads() { |
317 |
< |
final Semaphore lock = new Semaphore(1, false); |
318 |
< |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
319 |
< |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
320 |
< |
try { |
321 |
< |
assertFalse(lock.hasQueuedThreads()); |
322 |
< |
lock.acquireUninterruptibly(); |
323 |
< |
t1.start(); |
324 |
< |
Thread.sleep(SHORT_DELAY_MS); |
325 |
< |
assertTrue(lock.hasQueuedThreads()); |
326 |
< |
t2.start(); |
327 |
< |
Thread.sleep(SHORT_DELAY_MS); |
328 |
< |
assertTrue(lock.hasQueuedThreads()); |
329 |
< |
t1.interrupt(); |
330 |
< |
Thread.sleep(SHORT_DELAY_MS); |
331 |
< |
assertTrue(lock.hasQueuedThreads()); |
332 |
< |
lock.release(); |
333 |
< |
Thread.sleep(SHORT_DELAY_MS); |
334 |
< |
assertFalse(lock.hasQueuedThreads()); |
315 |
< |
t1.join(); |
316 |
< |
t2.join(); |
317 |
< |
} catch(Exception e){ |
318 |
< |
unexpectedException(); |
319 |
< |
} |
320 |
< |
} |
316 |
> |
public void testHasQueuedThreads() { testHasQueuedThreads(false); } |
317 |
> |
public void testHasQueuedThreads_fair() { testHasQueuedThreads(true); } |
318 |
> |
public void testHasQueuedThreads(boolean fair) { |
319 |
> |
final PublicSemaphore lock = new PublicSemaphore(1, fair); |
320 |
> |
assertFalse(lock.hasQueuedThreads()); |
321 |
> |
lock.acquireUninterruptibly(); |
322 |
> |
Thread t1 = newStartedThread(new InterruptedLockRunnable(lock)); |
323 |
> |
waitForQueuedThread(lock, t1); |
324 |
> |
assertTrue(lock.hasQueuedThreads()); |
325 |
> |
Thread t2 = newStartedThread(new InterruptibleLockRunnable(lock)); |
326 |
> |
waitForQueuedThread(lock, t2); |
327 |
> |
assertTrue(lock.hasQueuedThreads()); |
328 |
> |
t1.interrupt(); |
329 |
> |
awaitTermination(t1); |
330 |
> |
assertTrue(lock.hasQueuedThreads()); |
331 |
> |
lock.release(); |
332 |
> |
awaitTermination(t2); |
333 |
> |
assertFalse(lock.hasQueuedThreads()); |
334 |
> |
} |
335 |
|
|
336 |
|
/** |
337 |
|
* getQueueLength reports number of waiting threads |
338 |
|
*/ |
339 |
< |
public void testGetQueueLength() { |
340 |
< |
final Semaphore lock = new Semaphore(1, false); |
341 |
< |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
342 |
< |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
343 |
< |
try { |
344 |
< |
assertEquals(0, lock.getQueueLength()); |
345 |
< |
lock.acquireUninterruptibly(); |
346 |
< |
t1.start(); |
347 |
< |
Thread.sleep(SHORT_DELAY_MS); |
348 |
< |
assertEquals(1, lock.getQueueLength()); |
349 |
< |
t2.start(); |
350 |
< |
Thread.sleep(SHORT_DELAY_MS); |
351 |
< |
assertEquals(2, lock.getQueueLength()); |
352 |
< |
t1.interrupt(); |
353 |
< |
Thread.sleep(SHORT_DELAY_MS); |
354 |
< |
assertEquals(1, lock.getQueueLength()); |
355 |
< |
lock.release(); |
356 |
< |
Thread.sleep(SHORT_DELAY_MS); |
357 |
< |
assertEquals(0, lock.getQueueLength()); |
344 |
< |
t1.join(); |
345 |
< |
t2.join(); |
346 |
< |
} catch(Exception e){ |
347 |
< |
unexpectedException(); |
348 |
< |
} |
349 |
< |
} |
339 |
> |
public void testGetQueueLength() { testGetQueueLength(false); } |
340 |
> |
public void testGetQueueLength_fair() { testGetQueueLength(true); } |
341 |
> |
public void testGetQueueLength(boolean fair) { |
342 |
> |
final PublicSemaphore lock = new PublicSemaphore(1, fair); |
343 |
> |
assertEquals(0, lock.getQueueLength()); |
344 |
> |
lock.acquireUninterruptibly(); |
345 |
> |
Thread t1 = newStartedThread(new InterruptedLockRunnable(lock)); |
346 |
> |
waitForQueuedThread(lock, t1); |
347 |
> |
assertEquals(1, lock.getQueueLength()); |
348 |
> |
Thread t2 = newStartedThread(new InterruptibleLockRunnable(lock)); |
349 |
> |
waitForQueuedThread(lock, t2); |
350 |
> |
assertEquals(2, lock.getQueueLength()); |
351 |
> |
t1.interrupt(); |
352 |
> |
awaitTermination(t1); |
353 |
> |
assertEquals(1, lock.getQueueLength()); |
354 |
> |
lock.release(); |
355 |
> |
awaitTermination(t2); |
356 |
> |
assertEquals(0, lock.getQueueLength()); |
357 |
> |
} |
358 |
|
|
359 |
|
/** |
360 |
|
* getQueuedThreads includes waiting threads |
361 |
|
*/ |
362 |
< |
public void testGetQueuedThreads() { |
363 |
< |
final PublicSemaphore lock = new PublicSemaphore(1, false); |
364 |
< |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
365 |
< |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
366 |
< |
try { |
367 |
< |
assertTrue(lock.getQueuedThreads().isEmpty()); |
368 |
< |
lock.acquireUninterruptibly(); |
369 |
< |
assertTrue(lock.getQueuedThreads().isEmpty()); |
370 |
< |
t1.start(); |
371 |
< |
Thread.sleep(SHORT_DELAY_MS); |
372 |
< |
assertTrue(lock.getQueuedThreads().contains(t1)); |
373 |
< |
t2.start(); |
374 |
< |
Thread.sleep(SHORT_DELAY_MS); |
375 |
< |
assertTrue(lock.getQueuedThreads().contains(t1)); |
376 |
< |
assertTrue(lock.getQueuedThreads().contains(t2)); |
377 |
< |
t1.interrupt(); |
378 |
< |
Thread.sleep(SHORT_DELAY_MS); |
379 |
< |
assertFalse(lock.getQueuedThreads().contains(t1)); |
380 |
< |
assertTrue(lock.getQueuedThreads().contains(t2)); |
381 |
< |
lock.release(); |
382 |
< |
Thread.sleep(SHORT_DELAY_MS); |
383 |
< |
assertTrue(lock.getQueuedThreads().isEmpty()); |
376 |
< |
t1.join(); |
377 |
< |
t2.join(); |
378 |
< |
} catch(Exception e){ |
379 |
< |
unexpectedException(); |
380 |
< |
} |
381 |
< |
} |
362 |
> |
public void testGetQueuedThreads() { testGetQueuedThreads(false); } |
363 |
> |
public void testGetQueuedThreads_fair() { testGetQueuedThreads(true); } |
364 |
> |
public void testGetQueuedThreads(boolean fair) { |
365 |
> |
final PublicSemaphore lock = new PublicSemaphore(1, fair); |
366 |
> |
assertTrue(lock.getQueuedThreads().isEmpty()); |
367 |
> |
lock.acquireUninterruptibly(); |
368 |
> |
assertTrue(lock.getQueuedThreads().isEmpty()); |
369 |
> |
Thread t1 = newStartedThread(new InterruptedLockRunnable(lock)); |
370 |
> |
waitForQueuedThread(lock, t1); |
371 |
> |
assertTrue(lock.getQueuedThreads().contains(t1)); |
372 |
> |
Thread t2 = newStartedThread(new InterruptibleLockRunnable(lock)); |
373 |
> |
waitForQueuedThread(lock, t2); |
374 |
> |
assertTrue(lock.getQueuedThreads().contains(t1)); |
375 |
> |
assertTrue(lock.getQueuedThreads().contains(t2)); |
376 |
> |
t1.interrupt(); |
377 |
> |
awaitTermination(t1); |
378 |
> |
assertFalse(lock.getQueuedThreads().contains(t1)); |
379 |
> |
assertTrue(lock.getQueuedThreads().contains(t2)); |
380 |
> |
lock.release(); |
381 |
> |
awaitTermination(t2); |
382 |
> |
assertTrue(lock.getQueuedThreads().isEmpty()); |
383 |
> |
} |
384 |
|
|
385 |
|
/** |
386 |
|
* drainPermits reports and removes given number of permits |
387 |
|
*/ |
388 |
< |
public void testDrainPermits() { |
389 |
< |
Semaphore s = new Semaphore(0, false); |
388 |
> |
public void testDrainPermits() { testDrainPermits(false); } |
389 |
> |
public void testDrainPermits_fair() { testDrainPermits(true); } |
390 |
> |
public void testDrainPermits(boolean fair) { |
391 |
> |
Semaphore s = new Semaphore(0, fair); |
392 |
|
assertEquals(0, s.availablePermits()); |
393 |
|
assertEquals(0, s.drainPermits()); |
394 |
|
s.release(10); |
399 |
|
} |
400 |
|
|
401 |
|
/** |
402 |
< |
* reducePermits reduces number of permits |
402 |
> |
* release(-N) throws IllegalArgumentException |
403 |
|
*/ |
404 |
< |
public void testReducePermits() { |
405 |
< |
PublicSemaphore s = new PublicSemaphore(10, false); |
406 |
< |
assertEquals(10, s.availablePermits()); |
407 |
< |
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); |
404 |
> |
public void testReleaseIAE() { testReleaseIAE(false); } |
405 |
> |
public void testReleaseIAE_fair() { testReleaseIAE(true); } |
406 |
> |
public void testReleaseIAE(boolean fair) { |
407 |
> |
Semaphore s = new Semaphore(10, fair); |
408 |
|
try { |
409 |
< |
l.acquire(); |
410 |
< |
l.release(); |
411 |
< |
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 |
< |
} |
409 |
> |
s.release(-1); |
410 |
> |
shouldThrow(); |
411 |
> |
} catch (IllegalArgumentException success) {} |
412 |
|
} |
413 |
|
|
434 |
– |
|
414 |
|
/** |
415 |
< |
* Zero, negative, and positive initial values are allowed in constructor |
415 |
> |
* reducePermits(-N) throws IllegalArgumentException |
416 |
|
*/ |
417 |
< |
public void testConstructor_fair() { |
418 |
< |
Semaphore s0 = new Semaphore(0, true); |
419 |
< |
assertEquals(0, s0.availablePermits()); |
420 |
< |
assertTrue(s0.isFair()); |
421 |
< |
Semaphore s1 = new Semaphore(-1, true); |
422 |
< |
assertEquals(-1, s1.availablePermits()); |
423 |
< |
Semaphore s2 = new Semaphore(-1, true); |
424 |
< |
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()); |
417 |
> |
public void testReducePermitsIAE() { testReducePermitsIAE(false); } |
418 |
> |
public void testReducePermitsIAE_fair() { testReducePermitsIAE(true); } |
419 |
> |
public void testReducePermitsIAE(boolean fair) { |
420 |
> |
PublicSemaphore s = new PublicSemaphore(10, fair); |
421 |
> |
try { |
422 |
> |
s.reducePermits(-1); |
423 |
> |
shouldThrow(); |
424 |
> |
} catch (IllegalArgumentException success) {} |
425 |
|
} |
426 |
|
|
427 |
|
/** |
428 |
< |
* tryAcquire(n) succeeds when sufficient permits, else fails |
428 |
> |
* reducePermits reduces number of permits |
429 |
|
*/ |
430 |
< |
public void testTryAcquireNInSameThread_fair() { |
431 |
< |
Semaphore s = new Semaphore(2, true); |
432 |
< |
assertEquals(2, s.availablePermits()); |
433 |
< |
assertTrue(s.tryAcquire(2)); |
434 |
< |
assertEquals(0, s.availablePermits()); |
435 |
< |
assertFalse(s.tryAcquire()); |
430 |
> |
public void testReducePermits() { testReducePermits(false); } |
431 |
> |
public void testReducePermits_fair() { testReducePermits(true); } |
432 |
> |
public void testReducePermits(boolean fair) { |
433 |
> |
PublicSemaphore s = new PublicSemaphore(10, fair); |
434 |
> |
assertEquals(10, s.availablePermits()); |
435 |
> |
s.reducePermits(0); |
436 |
> |
assertEquals(10, s.availablePermits()); |
437 |
> |
s.reducePermits(1); |
438 |
> |
assertEquals(9, s.availablePermits()); |
439 |
> |
s.reducePermits(10); |
440 |
> |
assertEquals(-1, s.availablePermits()); |
441 |
> |
s.reducePermits(10); |
442 |
> |
assertEquals(-11, s.availablePermits()); |
443 |
> |
s.reducePermits(0); |
444 |
> |
assertEquals(-11, s.availablePermits()); |
445 |
|
} |
446 |
|
|
447 |
|
/** |
448 |
< |
* Acquire and release of semaphore succeed if initially available |
448 |
> |
* a reserialized semaphore has same number of permits and |
449 |
> |
* fairness, but no queued threads |
450 |
|
*/ |
451 |
< |
public void testAcquireReleaseInSameThread_fair() { |
452 |
< |
Semaphore s = new Semaphore(1, true); |
451 |
> |
public void testSerialization() { testSerialization(false); } |
452 |
> |
public void testSerialization_fair() { testSerialization(true); } |
453 |
> |
public void testSerialization(boolean fair) { |
454 |
|
try { |
455 |
+ |
Semaphore s = new Semaphore(3, fair); |
456 |
|
s.acquire(); |
478 |
– |
s.release(); |
479 |
– |
s.acquire(); |
480 |
– |
s.release(); |
481 |
– |
s.acquire(); |
482 |
– |
s.release(); |
457 |
|
s.acquire(); |
458 |
|
s.release(); |
485 |
– |
s.acquire(); |
486 |
– |
s.release(); |
487 |
– |
assertEquals(1, s.availablePermits()); |
488 |
– |
} catch( InterruptedException e){ |
489 |
– |
unexpectedException(); |
490 |
– |
} |
491 |
– |
} |
459 |
|
|
460 |
< |
/** |
461 |
< |
* Acquire(n) and release(n) of semaphore succeed if initially available |
462 |
< |
*/ |
463 |
< |
public void testAcquireReleaseNInSameThread_fair() { |
464 |
< |
Semaphore s = new Semaphore(1, true); |
465 |
< |
try { |
466 |
< |
s.release(1); |
467 |
< |
s.acquire(1); |
468 |
< |
s.release(2); |
469 |
< |
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 |
< |
} |
460 |
> |
Semaphore clone = serialClone(s); |
461 |
> |
assertEquals(fair, s.isFair()); |
462 |
> |
assertEquals(fair, clone.isFair()); |
463 |
> |
assertEquals(2, s.availablePermits()); |
464 |
> |
assertEquals(2, clone.availablePermits()); |
465 |
> |
clone.acquire(); |
466 |
> |
clone.acquire(); |
467 |
> |
clone.release(); |
468 |
> |
assertEquals(2, s.availablePermits()); |
469 |
> |
assertEquals(1, clone.availablePermits()); |
470 |
|
|
471 |
< |
/** |
472 |
< |
* Acquire(n) and release(n) of semaphore succeed if initially available |
473 |
< |
*/ |
474 |
< |
public void testAcquireUninterruptiblyReleaseNInSameThread_fair() { |
475 |
< |
Semaphore s = new Semaphore(1, true); |
476 |
< |
try { |
477 |
< |
s.release(1); |
478 |
< |
s.acquireUninterruptibly(1); |
479 |
< |
s.release(2); |
480 |
< |
s.acquireUninterruptibly(2); |
481 |
< |
s.release(3); |
482 |
< |
s.acquireUninterruptibly(3); |
483 |
< |
s.release(4); |
484 |
< |
s.acquireUninterruptibly(4); |
485 |
< |
s.release(5); |
530 |
< |
s.acquireUninterruptibly(5); |
531 |
< |
assertEquals(1, s.availablePermits()); |
532 |
< |
} finally { |
533 |
< |
} |
471 |
> |
s = new Semaphore(0, fair); |
472 |
> |
Thread t = newStartedThread(new InterruptibleLockRunnable(s)); |
473 |
> |
waitForQueuedThreads(s); |
474 |
> |
clone = serialClone(s); |
475 |
> |
assertEquals(fair, s.isFair()); |
476 |
> |
assertEquals(fair, clone.isFair()); |
477 |
> |
assertEquals(0, s.availablePermits()); |
478 |
> |
assertEquals(0, clone.availablePermits()); |
479 |
> |
assertTrue(s.hasQueuedThreads()); |
480 |
> |
assertFalse(clone.hasQueuedThreads()); |
481 |
> |
s.release(); |
482 |
> |
awaitTermination(t); |
483 |
> |
assertFalse(s.hasQueuedThreads()); |
484 |
> |
assertFalse(clone.hasQueuedThreads()); |
485 |
> |
} catch (InterruptedException e) { threadUnexpectedException(e); } |
486 |
|
} |
487 |
|
|
488 |
|
/** |
489 |
< |
* release(n) in one thread enables timed acquire(n) in another thread |
489 |
> |
* tryAcquire(n) succeeds when sufficient permits, else fails |
490 |
|
*/ |
491 |
< |
public void testTimedAcquireReleaseNInSameThread_fair() { |
492 |
< |
Semaphore s = new Semaphore(1, true); |
493 |
< |
try { |
494 |
< |
s.release(1); |
495 |
< |
assertTrue(s.tryAcquire(1, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
496 |
< |
s.release(2); |
497 |
< |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
498 |
< |
s.release(3); |
499 |
< |
assertTrue(s.tryAcquire(3, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
500 |
< |
s.release(4); |
501 |
< |
assertTrue(s.tryAcquire(4, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
502 |
< |
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 |
< |
} |
491 |
> |
public void testTryAcquireNInSameThread() { testTryAcquireNInSameThread(false); } |
492 |
> |
public void testTryAcquireNInSameThread_fair() { testTryAcquireNInSameThread(true); } |
493 |
> |
public void testTryAcquireNInSameThread(boolean fair) { |
494 |
> |
Semaphore s = new Semaphore(2, fair); |
495 |
> |
assertEquals(2, s.availablePermits()); |
496 |
> |
assertFalse(s.tryAcquire(3)); |
497 |
> |
assertEquals(2, s.availablePermits()); |
498 |
> |
assertTrue(s.tryAcquire(2)); |
499 |
> |
assertEquals(0, s.availablePermits()); |
500 |
> |
assertFalse(s.tryAcquire(1)); |
501 |
> |
assertFalse(s.tryAcquire(2)); |
502 |
> |
assertEquals(0, s.availablePermits()); |
503 |
|
} |
504 |
|
|
505 |
|
/** |
506 |
< |
* release in one thread enables timed acquire in another thread |
506 |
> |
* acquire succeeds if permits available |
507 |
|
*/ |
508 |
< |
public void testTimedAcquireReleaseInSameThread_fair() { |
509 |
< |
Semaphore s = new Semaphore(1, true); |
510 |
< |
try { |
511 |
< |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
512 |
< |
s.release(); |
513 |
< |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
514 |
< |
s.release(); |
515 |
< |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
516 |
< |
s.release(); |
517 |
< |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
518 |
< |
s.release(); |
519 |
< |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
520 |
< |
s.release(); |
508 |
> |
public void testReleaseAcquireSameThread_acquire() { testReleaseAcquireSameThread(false, AcquireMethod.acquire); } |
509 |
> |
public void testReleaseAcquireSameThread_acquire_fair() { testReleaseAcquireSameThread(true, AcquireMethod.acquire); } |
510 |
> |
public void testReleaseAcquireSameThread_acquireN() { testReleaseAcquireSameThread(false, AcquireMethod.acquireN); } |
511 |
> |
public void testReleaseAcquireSameThread_acquireN_fair() { testReleaseAcquireSameThread(true, AcquireMethod.acquireN); } |
512 |
> |
public void testReleaseAcquireSameThread_acquireUninterruptibly() { testReleaseAcquireSameThread(false, AcquireMethod.acquireUninterruptibly); } |
513 |
> |
public void testReleaseAcquireSameThread_acquireUninterruptibly_fair() { testReleaseAcquireSameThread(true, AcquireMethod.acquireUninterruptibly); } |
514 |
> |
public void testReleaseAcquireSameThread_acquireUninterruptiblyN() { testReleaseAcquireSameThread(false, AcquireMethod.acquireUninterruptibly); } |
515 |
> |
public void testReleaseAcquireSameThread_acquireUninterruptiblyN_fair() { testReleaseAcquireSameThread(true, AcquireMethod.acquireUninterruptibly); } |
516 |
> |
public void testReleaseAcquireSameThread_tryAcquire() { testReleaseAcquireSameThread(false, AcquireMethod.tryAcquire); } |
517 |
> |
public void testReleaseAcquireSameThread_tryAcquire_fair() { testReleaseAcquireSameThread(true, AcquireMethod.tryAcquire); } |
518 |
> |
public void testReleaseAcquireSameThread_tryAcquireN() { testReleaseAcquireSameThread(false, AcquireMethod.tryAcquireN); } |
519 |
> |
public void testReleaseAcquireSameThread_tryAcquireN_fair() { testReleaseAcquireSameThread(true, AcquireMethod.tryAcquireN); } |
520 |
> |
public void testReleaseAcquireSameThread_tryAcquireTimed() { testReleaseAcquireSameThread(false, AcquireMethod.tryAcquireTimed); } |
521 |
> |
public void testReleaseAcquireSameThread_tryAcquireTimed_fair() { testReleaseAcquireSameThread(true, AcquireMethod.tryAcquireTimed); } |
522 |
> |
public void testReleaseAcquireSameThread_tryAcquireTimedN() { testReleaseAcquireSameThread(false, AcquireMethod.tryAcquireTimedN); } |
523 |
> |
public void testReleaseAcquireSameThread_tryAcquireTimedN_fair() { testReleaseAcquireSameThread(true, AcquireMethod.tryAcquireTimedN); } |
524 |
> |
public void testReleaseAcquireSameThread(boolean fair, |
525 |
> |
final AcquireMethod acquirer) { |
526 |
> |
Semaphore s = new Semaphore(1, fair); |
527 |
> |
for (int i = 1; i < 6; i++) { |
528 |
> |
s.release(i); |
529 |
> |
assertEquals(1 + i, s.availablePermits()); |
530 |
> |
try { |
531 |
> |
acquirer.acquire(s, i); |
532 |
> |
} catch (InterruptedException e) { threadUnexpectedException(e); } |
533 |
|
assertEquals(1, s.availablePermits()); |
575 |
– |
} catch( InterruptedException e){ |
576 |
– |
unexpectedException(); |
534 |
|
} |
535 |
|
} |
536 |
|
|
537 |
|
/** |
538 |
< |
* A release in one thread enables an acquire in another thread |
538 |
> |
* release in one thread enables acquire in another thread |
539 |
|
*/ |
540 |
< |
public void testAcquireReleaseInDifferentThreads_fair() { |
541 |
< |
final Semaphore s = new Semaphore(0, true); |
542 |
< |
Thread t = new Thread(new Runnable() { |
543 |
< |
public void run() { |
544 |
< |
try { |
545 |
< |
s.acquire(); |
546 |
< |
s.acquire(); |
547 |
< |
s.acquire(); |
548 |
< |
s.acquire(); |
549 |
< |
} catch(InterruptedException ie){ |
550 |
< |
threadUnexpectedException(); |
551 |
< |
} |
552 |
< |
} |
553 |
< |
}); |
554 |
< |
try { |
555 |
< |
t.start(); |
556 |
< |
Thread.sleep(SHORT_DELAY_MS); |
557 |
< |
s.release(); |
558 |
< |
s.release(); |
559 |
< |
s.release(); |
560 |
< |
s.release(); |
561 |
< |
s.release(); |
562 |
< |
s.release(); |
563 |
< |
t.join(); |
564 |
< |
assertEquals(2, s.availablePermits()); |
565 |
< |
} catch( InterruptedException e){ |
566 |
< |
unexpectedException(); |
540 |
> |
public void testReleaseAcquireDifferentThreads_acquire() { testReleaseAcquireDifferentThreads(false, AcquireMethod.acquire); } |
541 |
> |
public void testReleaseAcquireDifferentThreads_acquire_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.acquire); } |
542 |
> |
public void testReleaseAcquireDifferentThreads_acquireN() { testReleaseAcquireDifferentThreads(false, AcquireMethod.acquireN); } |
543 |
> |
public void testReleaseAcquireDifferentThreads_acquireN_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.acquireN); } |
544 |
> |
public void testReleaseAcquireDifferentThreads_acquireUninterruptibly() { testReleaseAcquireDifferentThreads(false, AcquireMethod.acquireUninterruptibly); } |
545 |
> |
public void testReleaseAcquireDifferentThreads_acquireUninterruptibly_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.acquireUninterruptibly); } |
546 |
> |
public void testReleaseAcquireDifferentThreads_acquireUninterruptiblyN() { testReleaseAcquireDifferentThreads(false, AcquireMethod.acquireUninterruptibly); } |
547 |
> |
public void testReleaseAcquireDifferentThreads_acquireUninterruptiblyN_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.acquireUninterruptibly); } |
548 |
> |
public void testReleaseAcquireDifferentThreads_tryAcquireTimed() { testReleaseAcquireDifferentThreads(false, AcquireMethod.tryAcquireTimed); } |
549 |
> |
public void testReleaseAcquireDifferentThreads_tryAcquireTimed_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.tryAcquireTimed); } |
550 |
> |
public void testReleaseAcquireDifferentThreads_tryAcquireTimedN() { testReleaseAcquireDifferentThreads(false, AcquireMethod.tryAcquireTimedN); } |
551 |
> |
public void testReleaseAcquireDifferentThreads_tryAcquireTimedN_fair() { testReleaseAcquireDifferentThreads(true, AcquireMethod.tryAcquireTimedN); } |
552 |
> |
public void testReleaseAcquireDifferentThreads(boolean fair, |
553 |
> |
final AcquireMethod acquirer) { |
554 |
> |
final Semaphore s = new Semaphore(0, fair); |
555 |
> |
final int rounds = 4; |
556 |
> |
long startTime = System.nanoTime(); |
557 |
> |
Thread t = newStartedThread(new CheckedRunnable() { |
558 |
> |
public void realRun() throws InterruptedException { |
559 |
> |
for (int i = 0; i < rounds; i++) { |
560 |
> |
assertFalse(s.hasQueuedThreads()); |
561 |
> |
if (i % 2 == 0) |
562 |
> |
acquirer.acquire(s); |
563 |
> |
else |
564 |
> |
acquirer.acquire(s, 3); |
565 |
> |
}}}); |
566 |
> |
|
567 |
> |
for (int i = 0; i < rounds; i++) { |
568 |
> |
while (! (s.availablePermits() == 0 && s.hasQueuedThreads())) |
569 |
> |
Thread.yield(); |
570 |
> |
assertTrue(t.isAlive()); |
571 |
> |
if (i % 2 == 0) |
572 |
> |
s.release(); |
573 |
> |
else |
574 |
> |
s.release(3); |
575 |
|
} |
576 |
+ |
awaitTermination(t); |
577 |
+ |
assertEquals(0, s.availablePermits()); |
578 |
+ |
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); |
579 |
|
} |
580 |
|
|
581 |
|
/** |
582 |
< |
* release(n) in one thread enables acquire(n) in another thread |
582 |
> |
* fair locks are strictly FIFO |
583 |
|
*/ |
584 |
< |
public void testAcquireReleaseNInDifferentThreads_fair() { |
585 |
< |
final Semaphore s = new Semaphore(0, true); |
586 |
< |
Thread t = new Thread(new Runnable() { |
587 |
< |
public void run() { |
588 |
< |
try { |
589 |
< |
s.acquire(); |
590 |
< |
s.release(2); |
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(2); |
601 |
< |
s.acquire(2); |
602 |
< |
s.release(1); |
603 |
< |
t.join(); |
604 |
< |
} catch( InterruptedException e){ |
605 |
< |
unexpectedException(); |
606 |
< |
} |
584 |
> |
public void testFairLocksFifo() { |
585 |
> |
final PublicSemaphore s = new PublicSemaphore(1, true); |
586 |
> |
final CountDownLatch pleaseRelease = new CountDownLatch(1); |
587 |
> |
Thread t1 = newStartedThread(new CheckedRunnable() { |
588 |
> |
public void realRun() throws InterruptedException { |
589 |
> |
// Will block; permits are available, but not three |
590 |
> |
s.acquire(3); |
591 |
> |
}}); |
592 |
> |
|
593 |
> |
waitForQueuedThreads(s); |
594 |
> |
|
595 |
> |
Thread t2 = newStartedThread(new CheckedRunnable() { |
596 |
> |
public void realRun() throws InterruptedException { |
597 |
> |
// Will fail, even though 1 permit is available |
598 |
> |
assertFalse(s.tryAcquire(0L, MILLISECONDS)); |
599 |
> |
assertFalse(s.tryAcquire(1, 0L, MILLISECONDS)); |
600 |
> |
|
601 |
> |
// untimed tryAcquire will barge and succeed |
602 |
> |
assertTrue(s.tryAcquire()); |
603 |
> |
s.release(2); |
604 |
> |
assertTrue(s.tryAcquire(2)); |
605 |
> |
s.release(); |
606 |
> |
|
607 |
> |
pleaseRelease.countDown(); |
608 |
> |
// Will queue up behind t1, even though 1 permit is available |
609 |
> |
s.acquire(); |
610 |
> |
}}); |
611 |
> |
|
612 |
> |
await(pleaseRelease); |
613 |
> |
waitForQueuedThread(s, t2); |
614 |
> |
s.release(2); |
615 |
> |
awaitTermination(t1); |
616 |
> |
assertTrue(t2.isAlive()); |
617 |
> |
s.release(); |
618 |
> |
awaitTermination(t2); |
619 |
|
} |
620 |
|
|
641 |
– |
|
642 |
– |
|
621 |
|
/** |
622 |
< |
* release in one thread enables timed acquire in another thread |
623 |
< |
*/ |
624 |
< |
public void testTimedAcquireReleaseInDifferentThreads_fair() { |
625 |
< |
final Semaphore s = new Semaphore(1, true); |
626 |
< |
Thread t = new Thread(new Runnable() { |
627 |
< |
public void run() { |
628 |
< |
try { |
629 |
< |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
630 |
< |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
631 |
< |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
632 |
< |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
633 |
< |
threadAssertTrue(s.tryAcquire(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
634 |
< |
|
657 |
< |
} catch(InterruptedException ie){ |
658 |
< |
threadUnexpectedException(); |
659 |
< |
} |
660 |
< |
} |
661 |
< |
}); |
662 |
< |
t.start(); |
663 |
< |
try { |
664 |
< |
s.release(); |
665 |
< |
s.release(); |
666 |
< |
s.release(); |
667 |
< |
s.release(); |
668 |
< |
s.release(); |
669 |
< |
t.join(); |
670 |
< |
} catch( InterruptedException e){ |
671 |
< |
unexpectedException(); |
672 |
< |
} |
622 |
> |
* toString indicates current number of permits |
623 |
> |
*/ |
624 |
> |
public void testToString() { testToString(false); } |
625 |
> |
public void testToString_fair() { testToString(true); } |
626 |
> |
public void testToString(boolean fair) { |
627 |
> |
PublicSemaphore s = new PublicSemaphore(0, fair); |
628 |
> |
assertTrue(s.toString().contains("Permits = 0")); |
629 |
> |
s.release(); |
630 |
> |
assertTrue(s.toString().contains("Permits = 1")); |
631 |
> |
s.release(2); |
632 |
> |
assertTrue(s.toString().contains("Permits = 3")); |
633 |
> |
s.reducePermits(5); |
634 |
> |
assertTrue(s.toString().contains("Permits = -2")); |
635 |
|
} |
636 |
|
|
675 |
– |
/** |
676 |
– |
* release(n) in one thread enables timed acquire(n) in another thread |
677 |
– |
*/ |
678 |
– |
public void testTimedAcquireReleaseNInDifferentThreads_fair() { |
679 |
– |
final Semaphore s = new Semaphore(2, true); |
680 |
– |
Thread t = new Thread(new Runnable() { |
681 |
– |
public void run() { |
682 |
– |
try { |
683 |
– |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
684 |
– |
s.release(2); |
685 |
– |
threadAssertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
686 |
– |
s.release(2); |
687 |
– |
} catch(InterruptedException ie){ |
688 |
– |
threadUnexpectedException(); |
689 |
– |
} |
690 |
– |
} |
691 |
– |
}); |
692 |
– |
t.start(); |
693 |
– |
try { |
694 |
– |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
695 |
– |
s.release(2); |
696 |
– |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
697 |
– |
s.release(2); |
698 |
– |
t.join(); |
699 |
– |
} catch( InterruptedException e){ |
700 |
– |
unexpectedException(); |
701 |
– |
} |
702 |
– |
} |
703 |
– |
|
704 |
– |
/** |
705 |
– |
* A waiting acquire blocks interruptibly |
706 |
– |
*/ |
707 |
– |
public void testAcquire_InterruptedException_fair() { |
708 |
– |
final Semaphore s = new Semaphore(0, true); |
709 |
– |
Thread t = new Thread(new Runnable() { |
710 |
– |
public void run() { |
711 |
– |
try { |
712 |
– |
s.acquire(); |
713 |
– |
threadShouldThrow(); |
714 |
– |
} catch(InterruptedException success){} |
715 |
– |
} |
716 |
– |
}); |
717 |
– |
t.start(); |
718 |
– |
try { |
719 |
– |
Thread.sleep(SHORT_DELAY_MS); |
720 |
– |
t.interrupt(); |
721 |
– |
t.join(); |
722 |
– |
} catch(InterruptedException e){ |
723 |
– |
unexpectedException(); |
724 |
– |
} |
725 |
– |
} |
726 |
– |
|
727 |
– |
/** |
728 |
– |
* A waiting acquire(n) blocks interruptibly |
729 |
– |
*/ |
730 |
– |
public void testAcquireN_InterruptedException_fair() { |
731 |
– |
final Semaphore s = new Semaphore(2, true); |
732 |
– |
Thread t = new Thread(new Runnable() { |
733 |
– |
public void run() { |
734 |
– |
try { |
735 |
– |
s.acquire(3); |
736 |
– |
threadShouldThrow(); |
737 |
– |
} catch(InterruptedException success){} |
738 |
– |
} |
739 |
– |
}); |
740 |
– |
t.start(); |
741 |
– |
try { |
742 |
– |
Thread.sleep(SHORT_DELAY_MS); |
743 |
– |
t.interrupt(); |
744 |
– |
t.join(); |
745 |
– |
} catch(InterruptedException e){ |
746 |
– |
unexpectedException(); |
747 |
– |
} |
748 |
– |
} |
749 |
– |
|
750 |
– |
/** |
751 |
– |
* A waiting tryAcquire blocks interruptibly |
752 |
– |
*/ |
753 |
– |
public void testTryAcquire_InterruptedException_fair() { |
754 |
– |
final Semaphore s = new Semaphore(0, true); |
755 |
– |
Thread t = new Thread(new Runnable() { |
756 |
– |
public void run() { |
757 |
– |
try { |
758 |
– |
s.tryAcquire(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
759 |
– |
threadShouldThrow(); |
760 |
– |
} catch(InterruptedException success){ |
761 |
– |
} |
762 |
– |
} |
763 |
– |
}); |
764 |
– |
t.start(); |
765 |
– |
try { |
766 |
– |
Thread.sleep(SHORT_DELAY_MS); |
767 |
– |
t.interrupt(); |
768 |
– |
t.join(); |
769 |
– |
} catch(InterruptedException e){ |
770 |
– |
unexpectedException(); |
771 |
– |
} |
772 |
– |
} |
773 |
– |
|
774 |
– |
/** |
775 |
– |
* A waiting tryAcquire(n) blocks interruptibly |
776 |
– |
*/ |
777 |
– |
public void testTryAcquireN_InterruptedException_fair() { |
778 |
– |
final Semaphore s = new Semaphore(1, true); |
779 |
– |
Thread t = new Thread(new Runnable() { |
780 |
– |
public void run() { |
781 |
– |
try { |
782 |
– |
s.tryAcquire(4, MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
783 |
– |
threadShouldThrow(); |
784 |
– |
} catch(InterruptedException success){ |
785 |
– |
} |
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 |
– |
* getQueueLength reports number of waiting threads |
800 |
– |
*/ |
801 |
– |
public void testGetQueueLength_fair() { |
802 |
– |
final Semaphore lock = new Semaphore(1, true); |
803 |
– |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
804 |
– |
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
805 |
– |
try { |
806 |
– |
assertEquals(0, lock.getQueueLength()); |
807 |
– |
lock.acquireUninterruptibly(); |
808 |
– |
t1.start(); |
809 |
– |
Thread.sleep(SHORT_DELAY_MS); |
810 |
– |
assertEquals(1, lock.getQueueLength()); |
811 |
– |
t2.start(); |
812 |
– |
Thread.sleep(SHORT_DELAY_MS); |
813 |
– |
assertEquals(2, lock.getQueueLength()); |
814 |
– |
t1.interrupt(); |
815 |
– |
Thread.sleep(SHORT_DELAY_MS); |
816 |
– |
assertEquals(1, lock.getQueueLength()); |
817 |
– |
lock.release(); |
818 |
– |
Thread.sleep(SHORT_DELAY_MS); |
819 |
– |
assertEquals(0, lock.getQueueLength()); |
820 |
– |
t1.join(); |
821 |
– |
t2.join(); |
822 |
– |
} catch(Exception e){ |
823 |
– |
unexpectedException(); |
824 |
– |
} |
825 |
– |
} |
826 |
– |
|
827 |
– |
|
828 |
– |
/** |
829 |
– |
* a deserialized serialized semaphore has same number of permits |
830 |
– |
*/ |
831 |
– |
public void testSerialization_fair() { |
832 |
– |
Semaphore l = new Semaphore(3, true); |
833 |
– |
|
834 |
– |
try { |
835 |
– |
l.acquire(); |
836 |
– |
l.release(); |
837 |
– |
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
838 |
– |
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
839 |
– |
out.writeObject(l); |
840 |
– |
out.close(); |
841 |
– |
|
842 |
– |
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
843 |
– |
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
844 |
– |
Semaphore r = (Semaphore) in.readObject(); |
845 |
– |
assertEquals(3, r.availablePermits()); |
846 |
– |
assertTrue(r.isFair()); |
847 |
– |
r.acquire(); |
848 |
– |
r.release(); |
849 |
– |
} catch(Exception e){ |
850 |
– |
unexpectedException(); |
851 |
– |
} |
852 |
– |
} |
853 |
– |
|
854 |
– |
|
637 |
|
} |