1 |
/* |
2 |
* Written by Doug Lea with assistance from members of JCP JSR-166 |
3 |
* Expert Group and released to the public domain, as explained at |
4 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
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* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
* Pat Fisher, Mike Judd. |
7 |
*/ |
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|
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import static java.util.concurrent.TimeUnit.MILLISECONDS; |
10 |
|
11 |
import java.util.ArrayList; |
12 |
import java.util.Arrays; |
13 |
import java.util.Collection; |
14 |
import java.util.Iterator; |
15 |
import java.util.NoSuchElementException; |
16 |
import java.util.concurrent.BlockingQueue; |
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import java.util.concurrent.CountDownLatch; |
18 |
import java.util.concurrent.Executors; |
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import java.util.concurrent.ExecutorService; |
20 |
import java.util.concurrent.SynchronousQueue; |
21 |
import java.util.concurrent.ThreadLocalRandom; |
22 |
|
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import junit.framework.Test; |
24 |
|
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public class SynchronousQueueTest extends JSR166TestCase { |
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|
27 |
public static class Fair extends BlockingQueueTest { |
28 |
protected BlockingQueue emptyCollection() { |
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return new SynchronousQueue(true); |
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} |
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} |
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|
33 |
public static class NonFair extends BlockingQueueTest { |
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protected BlockingQueue emptyCollection() { |
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return new SynchronousQueue(false); |
36 |
} |
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} |
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|
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public static void main(String[] args) { |
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main(suite(), args); |
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} |
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|
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public static Test suite() { |
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return newTestSuite(SynchronousQueueTest.class, |
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new Fair().testSuite(), |
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new NonFair().testSuite()); |
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} |
48 |
|
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/** |
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* Any SynchronousQueue is both empty and full |
51 |
*/ |
52 |
public void testEmptyFull() { testEmptyFull(false); } |
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public void testEmptyFull_fair() { testEmptyFull(true); } |
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public void testEmptyFull(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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assertTrue(q.isEmpty()); |
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assertEquals(0, q.size()); |
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assertEquals(0, q.remainingCapacity()); |
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assertFalse(q.offer(zero)); |
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} |
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|
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/** |
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* offer fails if no active taker |
64 |
*/ |
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public void testOffer() { testOffer(false); } |
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public void testOffer_fair() { testOffer(true); } |
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public void testOffer(boolean fair) { |
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SynchronousQueue q = new SynchronousQueue(fair); |
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assertFalse(q.offer(one)); |
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} |
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|
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/** |
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* add throws IllegalStateException if no active taker |
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*/ |
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public void testAdd() { testAdd(false); } |
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public void testAdd_fair() { testAdd(true); } |
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public void testAdd(boolean fair) { |
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SynchronousQueue q = new SynchronousQueue(fair); |
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assertEquals(0, q.remainingCapacity()); |
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try { |
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q.add(one); |
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shouldThrow(); |
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} catch (IllegalStateException success) {} |
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} |
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|
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/** |
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* addAll(this) throws IllegalArgumentException |
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*/ |
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public void testAddAll_self() { testAddAll_self(false); } |
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public void testAddAll_self_fair() { testAddAll_self(true); } |
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public void testAddAll_self(boolean fair) { |
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SynchronousQueue q = new SynchronousQueue(fair); |
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try { |
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q.addAll(q); |
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shouldThrow(); |
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} catch (IllegalArgumentException success) {} |
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} |
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|
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/** |
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* addAll throws IllegalStateException if no active taker |
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*/ |
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public void testAddAll_ISE() { testAddAll_ISE(false); } |
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public void testAddAll_ISE_fair() { testAddAll_ISE(true); } |
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public void testAddAll_ISE(boolean fair) { |
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SynchronousQueue q = new SynchronousQueue(fair); |
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Integer[] ints = new Integer[1]; |
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for (int i = 0; i < ints.length; i++) |
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ints[i] = i; |
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Collection<Integer> coll = Arrays.asList(ints); |
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try { |
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q.addAll(coll); |
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shouldThrow(); |
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} catch (IllegalStateException success) {} |
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} |
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|
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/** |
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* put blocks interruptibly if no active taker |
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*/ |
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public void testBlockingPut() { testBlockingPut(false); } |
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public void testBlockingPut_fair() { testBlockingPut(true); } |
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public void testBlockingPut(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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final CountDownLatch pleaseInterrupt = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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Thread.currentThread().interrupt(); |
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try { |
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q.put(99); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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|
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pleaseInterrupt.countDown(); |
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try { |
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q.put(99); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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}}); |
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|
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await(pleaseInterrupt); |
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if (randomBoolean()) assertThreadBlocks(t, Thread.State.WAITING); |
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t.interrupt(); |
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awaitTermination(t); |
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assertEquals(0, q.remainingCapacity()); |
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} |
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|
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/** |
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* put blocks interruptibly waiting for take |
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*/ |
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public void testPutWithTake() { testPutWithTake(false); } |
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public void testPutWithTake_fair() { testPutWithTake(true); } |
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public void testPutWithTake(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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final CountDownLatch pleaseTake = new CountDownLatch(1); |
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final CountDownLatch pleaseInterrupt = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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pleaseTake.countDown(); |
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q.put(one); |
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|
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Thread.currentThread().interrupt(); |
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try { |
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q.put(99); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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|
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pleaseInterrupt.countDown(); |
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try { |
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q.put(99); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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}}); |
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|
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await(pleaseTake); |
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assertEquals(0, q.remainingCapacity()); |
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try { assertSame(one, q.take()); } |
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catch (InterruptedException e) { threadUnexpectedException(e); } |
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|
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await(pleaseInterrupt); |
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if (randomBoolean()) assertThreadBlocks(t, Thread.State.WAITING); |
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t.interrupt(); |
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awaitTermination(t); |
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assertEquals(0, q.remainingCapacity()); |
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} |
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|
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/** |
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* timed offer times out if elements not taken |
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*/ |
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public void testTimedOffer() { |
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final boolean fair = ThreadLocalRandom.current().nextBoolean(); |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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final CountDownLatch pleaseInterrupt = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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long startTime = System.nanoTime(); |
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|
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assertFalse(q.offer(new Object(), timeoutMillis(), MILLISECONDS)); |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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|
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Thread.currentThread().interrupt(); |
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try { |
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q.offer(new Object(), randomTimeout(), randomTimeUnit()); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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|
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pleaseInterrupt.countDown(); |
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try { |
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q.offer(new Object(), LONG_DELAY_MS, MILLISECONDS); |
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shouldThrow(); |
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} catch (InterruptedException success) {} |
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assertFalse(Thread.interrupted()); |
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|
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assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); |
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}}); |
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|
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await(pleaseInterrupt); |
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if (randomBoolean()) assertThreadBlocks(t, Thread.State.TIMED_WAITING); |
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t.interrupt(); |
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awaitTermination(t); |
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} |
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|
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/** |
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* poll return null if no active putter |
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*/ |
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public void testPoll() { testPoll(false); } |
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public void testPoll_fair() { testPoll(true); } |
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public void testPoll(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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assertNull(q.poll()); |
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} |
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|
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/** |
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* timed poll with zero timeout times out if no active putter |
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*/ |
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public void testTimedPoll0() { testTimedPoll0(false); } |
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public void testTimedPoll0_fair() { testTimedPoll0(true); } |
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public void testTimedPoll0(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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try { assertNull(q.poll(0, MILLISECONDS)); } |
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catch (InterruptedException e) { threadUnexpectedException(e); } |
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} |
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|
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/** |
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* timed poll with nonzero timeout times out if no active putter |
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*/ |
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public void testTimedPoll() { |
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final boolean fair = ThreadLocalRandom.current().nextBoolean(); |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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final long startTime = System.nanoTime(); |
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try { assertNull(q.poll(timeoutMillis(), MILLISECONDS)); } |
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catch (InterruptedException e) { threadUnexpectedException(e); } |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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} |
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|
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/** |
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* timed poll before a delayed offer times out, returning null; |
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* after offer succeeds; on interruption throws |
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*/ |
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public void testTimedPollWithOffer() { |
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final boolean fair = ThreadLocalRandom.current().nextBoolean(); |
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final SynchronousQueue q = new SynchronousQueue(fair); |
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final CountDownLatch pleaseOffer = new CountDownLatch(1); |
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final CountDownLatch pleaseInterrupt = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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long startTime = System.nanoTime(); |
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assertNull(q.poll(timeoutMillis(), MILLISECONDS)); |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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|
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pleaseOffer.countDown(); |
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startTime = System.nanoTime(); |
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assertSame(zero, q.poll(LONG_DELAY_MS, MILLISECONDS)); |
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|
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Thread.currentThread().interrupt(); |
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try { |
280 |
q.poll(randomTimeout(), randomTimeUnit()); |
281 |
shouldThrow(); |
282 |
} catch (InterruptedException success) {} |
283 |
assertFalse(Thread.interrupted()); |
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|
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pleaseInterrupt.countDown(); |
286 |
try { |
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q.poll(LONG_DELAY_MS, MILLISECONDS); |
288 |
shouldThrow(); |
289 |
} catch (InterruptedException success) {} |
290 |
assertFalse(Thread.interrupted()); |
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|
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assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); |
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}}); |
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|
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await(pleaseOffer); |
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long startTime = System.nanoTime(); |
297 |
try { assertTrue(q.offer(zero, LONG_DELAY_MS, MILLISECONDS)); } |
298 |
catch (InterruptedException e) { threadUnexpectedException(e); } |
299 |
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); |
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|
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await(pleaseInterrupt); |
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if (randomBoolean()) assertThreadBlocks(t, Thread.State.TIMED_WAITING); |
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t.interrupt(); |
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awaitTermination(t); |
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} |
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|
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/** |
308 |
* peek() returns null if no active putter |
309 |
*/ |
310 |
public void testPeek() { testPeek(false); } |
311 |
public void testPeek_fair() { testPeek(true); } |
312 |
public void testPeek(boolean fair) { |
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final SynchronousQueue q = new SynchronousQueue(fair); |
314 |
assertNull(q.peek()); |
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} |
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|
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/** |
318 |
* element() throws NoSuchElementException if no active putter |
319 |
*/ |
320 |
public void testElement() { testElement(false); } |
321 |
public void testElement_fair() { testElement(true); } |
322 |
public void testElement(boolean fair) { |
323 |
final SynchronousQueue q = new SynchronousQueue(fair); |
324 |
try { |
325 |
q.element(); |
326 |
shouldThrow(); |
327 |
} catch (NoSuchElementException success) {} |
328 |
} |
329 |
|
330 |
/** |
331 |
* remove() throws NoSuchElementException if no active putter |
332 |
*/ |
333 |
public void testRemove() { testRemove(false); } |
334 |
public void testRemove_fair() { testRemove(true); } |
335 |
public void testRemove(boolean fair) { |
336 |
final SynchronousQueue q = new SynchronousQueue(fair); |
337 |
try { |
338 |
q.remove(); |
339 |
shouldThrow(); |
340 |
} catch (NoSuchElementException success) {} |
341 |
} |
342 |
|
343 |
/** |
344 |
* contains returns false |
345 |
*/ |
346 |
public void testContains() { testContains(false); } |
347 |
public void testContains_fair() { testContains(true); } |
348 |
public void testContains(boolean fair) { |
349 |
final SynchronousQueue q = new SynchronousQueue(fair); |
350 |
assertFalse(q.contains(zero)); |
351 |
} |
352 |
|
353 |
/** |
354 |
* clear ensures isEmpty |
355 |
*/ |
356 |
public void testClear() { testClear(false); } |
357 |
public void testClear_fair() { testClear(true); } |
358 |
public void testClear(boolean fair) { |
359 |
final SynchronousQueue q = new SynchronousQueue(fair); |
360 |
q.clear(); |
361 |
assertTrue(q.isEmpty()); |
362 |
} |
363 |
|
364 |
/** |
365 |
* containsAll returns false unless empty |
366 |
*/ |
367 |
public void testContainsAll() { testContainsAll(false); } |
368 |
public void testContainsAll_fair() { testContainsAll(true); } |
369 |
public void testContainsAll(boolean fair) { |
370 |
final SynchronousQueue q = new SynchronousQueue(fair); |
371 |
Integer[] empty = new Integer[0]; |
372 |
assertTrue(q.containsAll(Arrays.asList(empty))); |
373 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
374 |
assertFalse(q.containsAll(Arrays.asList(ints))); |
375 |
} |
376 |
|
377 |
/** |
378 |
* retainAll returns false |
379 |
*/ |
380 |
public void testRetainAll() { testRetainAll(false); } |
381 |
public void testRetainAll_fair() { testRetainAll(true); } |
382 |
public void testRetainAll(boolean fair) { |
383 |
final SynchronousQueue q = new SynchronousQueue(fair); |
384 |
Integer[] empty = new Integer[0]; |
385 |
assertFalse(q.retainAll(Arrays.asList(empty))); |
386 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
387 |
assertFalse(q.retainAll(Arrays.asList(ints))); |
388 |
} |
389 |
|
390 |
/** |
391 |
* removeAll returns false |
392 |
*/ |
393 |
public void testRemoveAll() { testRemoveAll(false); } |
394 |
public void testRemoveAll_fair() { testRemoveAll(true); } |
395 |
public void testRemoveAll(boolean fair) { |
396 |
final SynchronousQueue q = new SynchronousQueue(fair); |
397 |
Integer[] empty = new Integer[0]; |
398 |
assertFalse(q.removeAll(Arrays.asList(empty))); |
399 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
400 |
assertFalse(q.containsAll(Arrays.asList(ints))); |
401 |
} |
402 |
|
403 |
/** |
404 |
* toArray is empty |
405 |
*/ |
406 |
public void testToArray() { testToArray(false); } |
407 |
public void testToArray_fair() { testToArray(true); } |
408 |
public void testToArray(boolean fair) { |
409 |
final SynchronousQueue q = new SynchronousQueue(fair); |
410 |
Object[] o = q.toArray(); |
411 |
assertEquals(0, o.length); |
412 |
} |
413 |
|
414 |
/** |
415 |
* toArray(Integer array) returns its argument with the first |
416 |
* element (if present) nulled out |
417 |
*/ |
418 |
public void testToArray2() { testToArray2(false); } |
419 |
public void testToArray2_fair() { testToArray2(true); } |
420 |
public void testToArray2(boolean fair) { |
421 |
final SynchronousQueue<Integer> q = new SynchronousQueue<>(fair); |
422 |
Integer[] a; |
423 |
|
424 |
a = new Integer[0]; |
425 |
assertSame(a, q.toArray(a)); |
426 |
|
427 |
a = new Integer[3]; |
428 |
Arrays.fill(a, 42); |
429 |
assertSame(a, q.toArray(a)); |
430 |
assertNull(a[0]); |
431 |
for (int i = 1; i < a.length; i++) |
432 |
assertEquals(42, (int) a[i]); |
433 |
} |
434 |
|
435 |
/** |
436 |
* toArray(null) throws NPE |
437 |
*/ |
438 |
public void testToArray_null() { testToArray_null(false); } |
439 |
public void testToArray_null_fair() { testToArray_null(true); } |
440 |
public void testToArray_null(boolean fair) { |
441 |
final SynchronousQueue q = new SynchronousQueue(fair); |
442 |
try { |
443 |
Object[] o = q.toArray((Object[])null); |
444 |
shouldThrow(); |
445 |
} catch (NullPointerException success) {} |
446 |
} |
447 |
|
448 |
/** |
449 |
* iterator does not traverse any elements |
450 |
*/ |
451 |
public void testIterator() { testIterator(false); } |
452 |
public void testIterator_fair() { testIterator(true); } |
453 |
public void testIterator(boolean fair) { |
454 |
assertIteratorExhausted(new SynchronousQueue(fair).iterator()); |
455 |
} |
456 |
|
457 |
/** |
458 |
* iterator remove throws IllegalStateException |
459 |
*/ |
460 |
public void testIteratorRemove() { testIteratorRemove(false); } |
461 |
public void testIteratorRemove_fair() { testIteratorRemove(true); } |
462 |
public void testIteratorRemove(boolean fair) { |
463 |
final SynchronousQueue q = new SynchronousQueue(fair); |
464 |
Iterator it = q.iterator(); |
465 |
try { |
466 |
it.remove(); |
467 |
shouldThrow(); |
468 |
} catch (IllegalStateException success) {} |
469 |
} |
470 |
|
471 |
/** |
472 |
* toString returns a non-null string |
473 |
*/ |
474 |
public void testToString() { testToString(false); } |
475 |
public void testToString_fair() { testToString(true); } |
476 |
public void testToString(boolean fair) { |
477 |
final SynchronousQueue q = new SynchronousQueue(fair); |
478 |
String s = q.toString(); |
479 |
assertNotNull(s); |
480 |
} |
481 |
|
482 |
/** |
483 |
* offer transfers elements across Executor tasks |
484 |
*/ |
485 |
public void testOfferInExecutor() { testOfferInExecutor(false); } |
486 |
public void testOfferInExecutor_fair() { testOfferInExecutor(true); } |
487 |
public void testOfferInExecutor(boolean fair) { |
488 |
final SynchronousQueue q = new SynchronousQueue(fair); |
489 |
final CheckedBarrier threadsStarted = new CheckedBarrier(2); |
490 |
final ExecutorService executor = Executors.newFixedThreadPool(2); |
491 |
try (PoolCleaner cleaner = cleaner(executor)) { |
492 |
|
493 |
executor.execute(new CheckedRunnable() { |
494 |
public void realRun() throws InterruptedException { |
495 |
assertFalse(q.offer(one)); |
496 |
threadsStarted.await(); |
497 |
assertTrue(q.offer(one, LONG_DELAY_MS, MILLISECONDS)); |
498 |
assertEquals(0, q.remainingCapacity()); |
499 |
}}); |
500 |
|
501 |
executor.execute(new CheckedRunnable() { |
502 |
public void realRun() throws InterruptedException { |
503 |
threadsStarted.await(); |
504 |
assertSame(one, q.take()); |
505 |
}}); |
506 |
} |
507 |
} |
508 |
|
509 |
/** |
510 |
* timed poll retrieves elements across Executor threads |
511 |
*/ |
512 |
public void testPollInExecutor() { testPollInExecutor(false); } |
513 |
public void testPollInExecutor_fair() { testPollInExecutor(true); } |
514 |
public void testPollInExecutor(boolean fair) { |
515 |
final SynchronousQueue q = new SynchronousQueue(fair); |
516 |
final CheckedBarrier threadsStarted = new CheckedBarrier(2); |
517 |
final ExecutorService executor = Executors.newFixedThreadPool(2); |
518 |
try (PoolCleaner cleaner = cleaner(executor)) { |
519 |
executor.execute(new CheckedRunnable() { |
520 |
public void realRun() throws InterruptedException { |
521 |
assertNull(q.poll()); |
522 |
threadsStarted.await(); |
523 |
assertSame(one, q.poll(LONG_DELAY_MS, MILLISECONDS)); |
524 |
assertTrue(q.isEmpty()); |
525 |
}}); |
526 |
|
527 |
executor.execute(new CheckedRunnable() { |
528 |
public void realRun() throws InterruptedException { |
529 |
threadsStarted.await(); |
530 |
q.put(one); |
531 |
}}); |
532 |
} |
533 |
} |
534 |
|
535 |
/** |
536 |
* a deserialized/reserialized queue is usable |
537 |
*/ |
538 |
public void testSerialization() { |
539 |
final SynchronousQueue x = new SynchronousQueue(); |
540 |
final SynchronousQueue y = new SynchronousQueue(false); |
541 |
final SynchronousQueue z = new SynchronousQueue(true); |
542 |
assertSerialEquals(x, y); |
543 |
assertNotSerialEquals(x, z); |
544 |
SynchronousQueue[] qs = { x, y, z }; |
545 |
for (SynchronousQueue q : qs) { |
546 |
SynchronousQueue clone = serialClone(q); |
547 |
assertNotSame(q, clone); |
548 |
assertSerialEquals(q, clone); |
549 |
assertTrue(clone.isEmpty()); |
550 |
assertEquals(0, clone.size()); |
551 |
assertEquals(0, clone.remainingCapacity()); |
552 |
assertFalse(clone.offer(zero)); |
553 |
} |
554 |
} |
555 |
|
556 |
/** |
557 |
* drainTo(c) of empty queue doesn't transfer elements |
558 |
*/ |
559 |
public void testDrainTo() { testDrainTo(false); } |
560 |
public void testDrainTo_fair() { testDrainTo(true); } |
561 |
public void testDrainTo(boolean fair) { |
562 |
final SynchronousQueue q = new SynchronousQueue(fair); |
563 |
ArrayList l = new ArrayList(); |
564 |
q.drainTo(l); |
565 |
assertEquals(0, q.size()); |
566 |
assertEquals(0, l.size()); |
567 |
} |
568 |
|
569 |
/** |
570 |
* drainTo empties queue, unblocking a waiting put. |
571 |
*/ |
572 |
public void testDrainToWithActivePut() { testDrainToWithActivePut(false); } |
573 |
public void testDrainToWithActivePut_fair() { testDrainToWithActivePut(true); } |
574 |
public void testDrainToWithActivePut(boolean fair) { |
575 |
final SynchronousQueue q = new SynchronousQueue(fair); |
576 |
Thread t = newStartedThread(new CheckedRunnable() { |
577 |
public void realRun() throws InterruptedException { |
578 |
q.put(one); |
579 |
}}); |
580 |
|
581 |
ArrayList l = new ArrayList(); |
582 |
long startTime = System.nanoTime(); |
583 |
while (l.isEmpty()) { |
584 |
q.drainTo(l); |
585 |
if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
586 |
fail("timed out"); |
587 |
Thread.yield(); |
588 |
} |
589 |
assertEquals(1, l.size()); |
590 |
assertSame(one, l.get(0)); |
591 |
awaitTermination(t); |
592 |
} |
593 |
|
594 |
/** |
595 |
* drainTo(c, n) empties up to n elements of queue into c |
596 |
*/ |
597 |
public void testDrainToN() throws InterruptedException { |
598 |
final SynchronousQueue q = new SynchronousQueue(); |
599 |
Thread t1 = newStartedThread(new CheckedRunnable() { |
600 |
public void realRun() throws InterruptedException { |
601 |
q.put(one); |
602 |
}}); |
603 |
|
604 |
Thread t2 = newStartedThread(new CheckedRunnable() { |
605 |
public void realRun() throws InterruptedException { |
606 |
q.put(two); |
607 |
}}); |
608 |
|
609 |
ArrayList l = new ArrayList(); |
610 |
int drained; |
611 |
while ((drained = q.drainTo(l, 1)) == 0) Thread.yield(); |
612 |
assertEquals(1, drained); |
613 |
assertEquals(1, l.size()); |
614 |
while ((drained = q.drainTo(l, 1)) == 0) Thread.yield(); |
615 |
assertEquals(1, drained); |
616 |
assertEquals(2, l.size()); |
617 |
assertTrue(l.contains(one)); |
618 |
assertTrue(l.contains(two)); |
619 |
awaitTermination(t1); |
620 |
awaitTermination(t2); |
621 |
} |
622 |
|
623 |
/** |
624 |
* remove(null), contains(null) always return false |
625 |
*/ |
626 |
public void testNeverContainsNull() { |
627 |
Collection<?> q = new SynchronousQueue(); |
628 |
assertFalse(q.contains(null)); |
629 |
assertFalse(q.remove(null)); |
630 |
} |
631 |
|
632 |
} |