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/ |
5 |
* 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 |
|
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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; |
19 |
import java.util.concurrent.ExecutorService; |
20 |
import java.util.concurrent.SynchronousQueue; |
21 |
|
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import junit.framework.Test; |
23 |
|
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public class SynchronousQueueTest extends JSR166TestCase { |
25 |
|
26 |
public static class Fair extends BlockingQueueTest { |
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protected BlockingQueue emptyCollection() { |
28 |
return new SynchronousQueue(true); |
29 |
} |
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} |
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|
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public static class NonFair extends BlockingQueueTest { |
33 |
protected BlockingQueue emptyCollection() { |
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return new SynchronousQueue(false); |
35 |
} |
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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, |
44 |
new Fair().testSuite(), |
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new NonFair().testSuite()); |
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} |
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|
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/** |
49 |
* Any SynchronousQueue is both empty and full |
50 |
*/ |
51 |
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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} |
60 |
|
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/** |
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* offer fails if no active taker |
63 |
*/ |
64 |
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()); |
79 |
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 |
100 |
*/ |
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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() { |
124 |
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) {} |
173 |
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 = randomBoolean(); |
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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 = randomBoolean(); |
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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 = randomBoolean(); |
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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() { |
268 |
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(); |
275 |
assertSame(zero, q.poll(LONG_DELAY_MS, MILLISECONDS)); |
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|
277 |
Thread.currentThread().interrupt(); |
278 |
try { |
279 |
q.poll(randomTimeout(), randomTimeUnit()); |
280 |
shouldThrow(); |
281 |
} catch (InterruptedException success) {} |
282 |
assertFalse(Thread.interrupted()); |
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|
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pleaseInterrupt.countDown(); |
285 |
try { |
286 |
q.poll(LONG_DELAY_MS, MILLISECONDS); |
287 |
shouldThrow(); |
288 |
} catch (InterruptedException success) {} |
289 |
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(); |
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try { assertTrue(q.offer(zero, LONG_DELAY_MS, MILLISECONDS)); } |
297 |
catch (InterruptedException e) { threadUnexpectedException(e); } |
298 |
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS); |
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|
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await(pleaseInterrupt); |
301 |
if (randomBoolean()) assertThreadBlocks(t, Thread.State.TIMED_WAITING); |
302 |
t.interrupt(); |
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awaitTermination(t); |
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} |
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|
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/** |
307 |
* peek() returns null if no active putter |
308 |
*/ |
309 |
public void testPeek() { testPeek(false); } |
310 |
public void testPeek_fair() { testPeek(true); } |
311 |
public void testPeek(boolean fair) { |
312 |
final SynchronousQueue q = new SynchronousQueue(fair); |
313 |
assertNull(q.peek()); |
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} |
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|
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/** |
317 |
* element() throws NoSuchElementException if no active putter |
318 |
*/ |
319 |
public void testElement() { testElement(false); } |
320 |
public void testElement_fair() { testElement(true); } |
321 |
public void testElement(boolean fair) { |
322 |
final SynchronousQueue q = new SynchronousQueue(fair); |
323 |
try { |
324 |
q.element(); |
325 |
shouldThrow(); |
326 |
} catch (NoSuchElementException success) {} |
327 |
} |
328 |
|
329 |
/** |
330 |
* remove() throws NoSuchElementException if no active putter |
331 |
*/ |
332 |
public void testRemove() { testRemove(false); } |
333 |
public void testRemove_fair() { testRemove(true); } |
334 |
public void testRemove(boolean fair) { |
335 |
final SynchronousQueue q = new SynchronousQueue(fair); |
336 |
try { |
337 |
q.remove(); |
338 |
shouldThrow(); |
339 |
} catch (NoSuchElementException success) {} |
340 |
} |
341 |
|
342 |
/** |
343 |
* contains returns false |
344 |
*/ |
345 |
public void testContains() { testContains(false); } |
346 |
public void testContains_fair() { testContains(true); } |
347 |
public void testContains(boolean fair) { |
348 |
final SynchronousQueue q = new SynchronousQueue(fair); |
349 |
assertFalse(q.contains(zero)); |
350 |
} |
351 |
|
352 |
/** |
353 |
* clear ensures isEmpty |
354 |
*/ |
355 |
public void testClear() { testClear(false); } |
356 |
public void testClear_fair() { testClear(true); } |
357 |
public void testClear(boolean fair) { |
358 |
final SynchronousQueue q = new SynchronousQueue(fair); |
359 |
q.clear(); |
360 |
assertTrue(q.isEmpty()); |
361 |
} |
362 |
|
363 |
/** |
364 |
* containsAll returns false unless empty |
365 |
*/ |
366 |
public void testContainsAll() { testContainsAll(false); } |
367 |
public void testContainsAll_fair() { testContainsAll(true); } |
368 |
public void testContainsAll(boolean fair) { |
369 |
final SynchronousQueue q = new SynchronousQueue(fair); |
370 |
Integer[] empty = new Integer[0]; |
371 |
assertTrue(q.containsAll(Arrays.asList(empty))); |
372 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
373 |
assertFalse(q.containsAll(Arrays.asList(ints))); |
374 |
} |
375 |
|
376 |
/** |
377 |
* retainAll returns false |
378 |
*/ |
379 |
public void testRetainAll() { testRetainAll(false); } |
380 |
public void testRetainAll_fair() { testRetainAll(true); } |
381 |
public void testRetainAll(boolean fair) { |
382 |
final SynchronousQueue q = new SynchronousQueue(fair); |
383 |
Integer[] empty = new Integer[0]; |
384 |
assertFalse(q.retainAll(Arrays.asList(empty))); |
385 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
386 |
assertFalse(q.retainAll(Arrays.asList(ints))); |
387 |
} |
388 |
|
389 |
/** |
390 |
* removeAll returns false |
391 |
*/ |
392 |
public void testRemoveAll() { testRemoveAll(false); } |
393 |
public void testRemoveAll_fair() { testRemoveAll(true); } |
394 |
public void testRemoveAll(boolean fair) { |
395 |
final SynchronousQueue q = new SynchronousQueue(fair); |
396 |
Integer[] empty = new Integer[0]; |
397 |
assertFalse(q.removeAll(Arrays.asList(empty))); |
398 |
Integer[] ints = new Integer[1]; ints[0] = zero; |
399 |
assertFalse(q.containsAll(Arrays.asList(ints))); |
400 |
} |
401 |
|
402 |
/** |
403 |
* toArray is empty |
404 |
*/ |
405 |
public void testToArray() { testToArray(false); } |
406 |
public void testToArray_fair() { testToArray(true); } |
407 |
public void testToArray(boolean fair) { |
408 |
final SynchronousQueue q = new SynchronousQueue(fair); |
409 |
Object[] o = q.toArray(); |
410 |
assertEquals(0, o.length); |
411 |
} |
412 |
|
413 |
/** |
414 |
* toArray(Integer array) returns its argument with the first |
415 |
* element (if present) nulled out |
416 |
*/ |
417 |
public void testToArray2() { testToArray2(false); } |
418 |
public void testToArray2_fair() { testToArray2(true); } |
419 |
public void testToArray2(boolean fair) { |
420 |
final SynchronousQueue<Integer> q = new SynchronousQueue<>(fair); |
421 |
Integer[] a; |
422 |
|
423 |
a = new Integer[0]; |
424 |
assertSame(a, q.toArray(a)); |
425 |
|
426 |
a = new Integer[3]; |
427 |
Arrays.fill(a, 42); |
428 |
assertSame(a, q.toArray(a)); |
429 |
assertNull(a[0]); |
430 |
for (int i = 1; i < a.length; i++) |
431 |
assertEquals(42, (int) a[i]); |
432 |
} |
433 |
|
434 |
/** |
435 |
* toArray(null) throws NPE |
436 |
*/ |
437 |
public void testToArray_null() { testToArray_null(false); } |
438 |
public void testToArray_null_fair() { testToArray_null(true); } |
439 |
public void testToArray_null(boolean fair) { |
440 |
final SynchronousQueue q = new SynchronousQueue(fair); |
441 |
try { |
442 |
Object[] o = q.toArray((Object[])null); |
443 |
shouldThrow(); |
444 |
} catch (NullPointerException success) {} |
445 |
} |
446 |
|
447 |
/** |
448 |
* iterator does not traverse any elements |
449 |
*/ |
450 |
public void testIterator() { testIterator(false); } |
451 |
public void testIterator_fair() { testIterator(true); } |
452 |
public void testIterator(boolean fair) { |
453 |
assertIteratorExhausted(new SynchronousQueue(fair).iterator()); |
454 |
} |
455 |
|
456 |
/** |
457 |
* iterator remove throws IllegalStateException |
458 |
*/ |
459 |
public void testIteratorRemove() { testIteratorRemove(false); } |
460 |
public void testIteratorRemove_fair() { testIteratorRemove(true); } |
461 |
public void testIteratorRemove(boolean fair) { |
462 |
final SynchronousQueue q = new SynchronousQueue(fair); |
463 |
Iterator it = q.iterator(); |
464 |
try { |
465 |
it.remove(); |
466 |
shouldThrow(); |
467 |
} catch (IllegalStateException success) {} |
468 |
} |
469 |
|
470 |
/** |
471 |
* toString returns a non-null string |
472 |
*/ |
473 |
public void testToString() { testToString(false); } |
474 |
public void testToString_fair() { testToString(true); } |
475 |
public void testToString(boolean fair) { |
476 |
final SynchronousQueue q = new SynchronousQueue(fair); |
477 |
String s = q.toString(); |
478 |
assertNotNull(s); |
479 |
} |
480 |
|
481 |
/** |
482 |
* offer transfers elements across Executor tasks |
483 |
*/ |
484 |
public void testOfferInExecutor() { testOfferInExecutor(false); } |
485 |
public void testOfferInExecutor_fair() { testOfferInExecutor(true); } |
486 |
public void testOfferInExecutor(boolean fair) { |
487 |
final SynchronousQueue q = new SynchronousQueue(fair); |
488 |
final CheckedBarrier threadsStarted = new CheckedBarrier(2); |
489 |
final ExecutorService executor = Executors.newFixedThreadPool(2); |
490 |
try (PoolCleaner cleaner = cleaner(executor)) { |
491 |
|
492 |
executor.execute(new CheckedRunnable() { |
493 |
public void realRun() throws InterruptedException { |
494 |
assertFalse(q.offer(one)); |
495 |
threadsStarted.await(); |
496 |
assertTrue(q.offer(one, LONG_DELAY_MS, MILLISECONDS)); |
497 |
assertEquals(0, q.remainingCapacity()); |
498 |
}}); |
499 |
|
500 |
executor.execute(new CheckedRunnable() { |
501 |
public void realRun() throws InterruptedException { |
502 |
threadsStarted.await(); |
503 |
assertSame(one, q.take()); |
504 |
}}); |
505 |
} |
506 |
} |
507 |
|
508 |
/** |
509 |
* timed poll retrieves elements across Executor threads |
510 |
*/ |
511 |
public void testPollInExecutor() { testPollInExecutor(false); } |
512 |
public void testPollInExecutor_fair() { testPollInExecutor(true); } |
513 |
public void testPollInExecutor(boolean fair) { |
514 |
final SynchronousQueue q = new SynchronousQueue(fair); |
515 |
final CheckedBarrier threadsStarted = new CheckedBarrier(2); |
516 |
final ExecutorService executor = Executors.newFixedThreadPool(2); |
517 |
try (PoolCleaner cleaner = cleaner(executor)) { |
518 |
executor.execute(new CheckedRunnable() { |
519 |
public void realRun() throws InterruptedException { |
520 |
assertNull(q.poll()); |
521 |
threadsStarted.await(); |
522 |
assertSame(one, q.poll(LONG_DELAY_MS, MILLISECONDS)); |
523 |
assertTrue(q.isEmpty()); |
524 |
}}); |
525 |
|
526 |
executor.execute(new CheckedRunnable() { |
527 |
public void realRun() throws InterruptedException { |
528 |
threadsStarted.await(); |
529 |
q.put(one); |
530 |
}}); |
531 |
} |
532 |
} |
533 |
|
534 |
/** |
535 |
* a deserialized/reserialized queue is usable |
536 |
*/ |
537 |
public void testSerialization() { |
538 |
final SynchronousQueue x = new SynchronousQueue(); |
539 |
final SynchronousQueue y = new SynchronousQueue(false); |
540 |
final SynchronousQueue z = new SynchronousQueue(true); |
541 |
assertSerialEquals(x, y); |
542 |
assertNotSerialEquals(x, z); |
543 |
SynchronousQueue[] qs = { x, y, z }; |
544 |
for (SynchronousQueue q : qs) { |
545 |
SynchronousQueue clone = serialClone(q); |
546 |
assertNotSame(q, clone); |
547 |
assertSerialEquals(q, clone); |
548 |
assertTrue(clone.isEmpty()); |
549 |
assertEquals(0, clone.size()); |
550 |
assertEquals(0, clone.remainingCapacity()); |
551 |
assertFalse(clone.offer(zero)); |
552 |
} |
553 |
} |
554 |
|
555 |
/** |
556 |
* drainTo(c) of empty queue doesn't transfer elements |
557 |
*/ |
558 |
public void testDrainTo() { testDrainTo(false); } |
559 |
public void testDrainTo_fair() { testDrainTo(true); } |
560 |
public void testDrainTo(boolean fair) { |
561 |
final SynchronousQueue q = new SynchronousQueue(fair); |
562 |
ArrayList l = new ArrayList(); |
563 |
q.drainTo(l); |
564 |
assertEquals(0, q.size()); |
565 |
assertEquals(0, l.size()); |
566 |
} |
567 |
|
568 |
/** |
569 |
* drainTo empties queue, unblocking a waiting put. |
570 |
*/ |
571 |
public void testDrainToWithActivePut() { testDrainToWithActivePut(false); } |
572 |
public void testDrainToWithActivePut_fair() { testDrainToWithActivePut(true); } |
573 |
public void testDrainToWithActivePut(boolean fair) { |
574 |
final SynchronousQueue q = new SynchronousQueue(fair); |
575 |
Thread t = newStartedThread(new CheckedRunnable() { |
576 |
public void realRun() throws InterruptedException { |
577 |
q.put(one); |
578 |
}}); |
579 |
|
580 |
ArrayList l = new ArrayList(); |
581 |
long startTime = System.nanoTime(); |
582 |
while (l.isEmpty()) { |
583 |
q.drainTo(l); |
584 |
if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
585 |
fail("timed out"); |
586 |
Thread.yield(); |
587 |
} |
588 |
assertEquals(1, l.size()); |
589 |
assertSame(one, l.get(0)); |
590 |
awaitTermination(t); |
591 |
} |
592 |
|
593 |
/** |
594 |
* drainTo(c, n) empties up to n elements of queue into c |
595 |
*/ |
596 |
public void testDrainToN() throws InterruptedException { |
597 |
final SynchronousQueue q = new SynchronousQueue(); |
598 |
Thread t1 = newStartedThread(new CheckedRunnable() { |
599 |
public void realRun() throws InterruptedException { |
600 |
q.put(one); |
601 |
}}); |
602 |
|
603 |
Thread t2 = newStartedThread(new CheckedRunnable() { |
604 |
public void realRun() throws InterruptedException { |
605 |
q.put(two); |
606 |
}}); |
607 |
|
608 |
ArrayList l = new ArrayList(); |
609 |
int drained; |
610 |
while ((drained = q.drainTo(l, 1)) == 0) Thread.yield(); |
611 |
assertEquals(1, drained); |
612 |
assertEquals(1, l.size()); |
613 |
while ((drained = q.drainTo(l, 1)) == 0) Thread.yield(); |
614 |
assertEquals(1, drained); |
615 |
assertEquals(2, l.size()); |
616 |
assertTrue(l.contains(one)); |
617 |
assertTrue(l.contains(two)); |
618 |
awaitTermination(t1); |
619 |
awaitTermination(t2); |
620 |
} |
621 |
|
622 |
/** |
623 |
* remove(null), contains(null) always return false |
624 |
*/ |
625 |
public void testNeverContainsNull() { |
626 |
Collection<?> q = new SynchronousQueue(); |
627 |
assertFalse(q.contains(null)); |
628 |
assertFalse(q.remove(null)); |
629 |
} |
630 |
|
631 |
} |