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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/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 static java.util.concurrent.TimeUnit.MILLISECONDS; |
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|
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import java.util.concurrent.CountDownLatch; |
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import java.util.concurrent.Exchanger; |
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import java.util.concurrent.TimeoutException; |
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|
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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 ExchangerTest extends JSR166TestCase { |
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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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public static Test suite() { |
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return new TestSuite(ExchangerTest.class); |
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} |
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|
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/** |
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* exchange exchanges objects across two threads |
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*/ |
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public void testExchange() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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Thread t1 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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assertSame(one, e.exchange(two)); |
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assertSame(two, e.exchange(one)); |
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}}); |
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Thread t2 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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assertSame(two, e.exchange(one)); |
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assertSame(one, e.exchange(two)); |
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}}); |
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|
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awaitTermination(t1); |
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awaitTermination(t2); |
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} |
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|
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/** |
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* timed exchange exchanges objects across two threads |
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*/ |
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public void testTimedExchange() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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Thread t1 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws Exception { |
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assertSame(one, e.exchange(two, LONG_DELAY_MS, MILLISECONDS)); |
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assertSame(two, e.exchange(one, LONG_DELAY_MS, MILLISECONDS)); |
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}}); |
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Thread t2 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws Exception { |
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assertSame(two, e.exchange(one, LONG_DELAY_MS, MILLISECONDS)); |
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assertSame(one, e.exchange(two, LONG_DELAY_MS, MILLISECONDS)); |
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}}); |
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|
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awaitTermination(t1); |
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awaitTermination(t2); |
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} |
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|
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/** |
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* interrupt during wait for exchange throws InterruptedException |
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*/ |
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public void testExchange_InterruptedException() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
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public void realRun() throws InterruptedException { |
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threadStarted.countDown(); |
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e.exchange(one); |
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}}); |
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|
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await(threadStarted); |
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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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* interrupt during wait for timed exchange throws InterruptedException |
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*/ |
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public void testTimedExchange_InterruptedException() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
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public void realRun() throws Exception { |
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threadStarted.countDown(); |
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e.exchange(null, LONG_DELAY_MS, MILLISECONDS); |
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}}); |
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|
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await(threadStarted); |
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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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* timeout during wait for timed exchange throws TimeoutException |
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*/ |
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public void testExchange_TimeoutException() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws Exception { |
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long startTime = System.nanoTime(); |
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try { |
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e.exchange(null, timeoutMillis(), MILLISECONDS); |
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shouldThrow(); |
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} catch (TimeoutException success) {} |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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}}); |
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|
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awaitTermination(t); |
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} |
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|
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/** |
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* If one exchanging thread is interrupted, another succeeds. |
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*/ |
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public void testReplacementAfterExchange() { |
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final Exchanger<Item> e = new Exchanger<Item>(); |
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final CountDownLatch exchanged = new CountDownLatch(2); |
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final CountDownLatch interrupted = new CountDownLatch(1); |
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Thread t1 = newStartedThread(new CheckedInterruptedRunnable() { |
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public void realRun() throws InterruptedException { |
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assertSame(two, e.exchange(one)); |
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exchanged.countDown(); |
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e.exchange(two); |
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}}); |
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Thread t2 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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assertSame(one, e.exchange(two)); |
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exchanged.countDown(); |
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await(interrupted); |
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assertSame(three, e.exchange(one)); |
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}}); |
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Thread t3 = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws InterruptedException { |
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await(interrupted); |
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assertSame(one, e.exchange(three)); |
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}}); |
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|
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await(exchanged); |
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t1.interrupt(); |
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awaitTermination(t1); |
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interrupted.countDown(); |
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awaitTermination(t2); |
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awaitTermination(t3); |
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} |
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|
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} |