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/* |
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* Written by members of JCP JSR-166 Expert Group and released to the |
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* public domain. Use, modify, and redistribute this code in any way |
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* without acknowledgement. Other contributors include Andrew Wright, |
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* Jeffrey Hayes, Pat Fischer, 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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|
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public class CountDownLatchTest 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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} |
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public static Test suite() { |
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return new TestSuite(CountDownLatchTest.class); |
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} |
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|
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/** |
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* negative constructor argument throws IAE |
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*/ |
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public void testConstructor() { |
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try { |
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new CountDownLatch(-1); |
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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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* getCount returns initial count and decreases after countDown |
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*/ |
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public void testGetCount() { |
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final CountDownLatch l = new CountDownLatch(2); |
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assertEquals(2, l.getCount()); |
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l.countDown(); |
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assertEquals(1, l.getCount()); |
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} |
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|
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/** |
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* countDown decrements count when positive and has no effect when zero |
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*/ |
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public void testCountDown() { |
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final CountDownLatch l = new CountDownLatch(1); |
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assertEquals(1, l.getCount()); |
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l.countDown(); |
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assertEquals(0, l.getCount()); |
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l.countDown(); |
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assertEquals(0, l.getCount()); |
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} |
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|
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/** |
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* await returns after countDown to zero, but not before |
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*/ |
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public void testAwait() { |
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final CountDownLatch l = new CountDownLatch(2); |
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|
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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try { |
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threadAssertTrue(l.getCount() > 0); |
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l.await(); |
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threadAssertTrue(l.getCount() == 0); |
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} catch(InterruptedException e){ |
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threadUnexpectedException(); |
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} |
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} |
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}); |
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t.start(); |
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try { |
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assertEquals(l.getCount(), 2); |
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Thread.sleep(SHORT_DELAY_MS); |
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l.countDown(); |
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assertEquals(l.getCount(), 1); |
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l.countDown(); |
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assertEquals(l.getCount(), 0); |
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t.join(); |
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} catch (InterruptedException e){ |
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unexpectedException(); |
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} |
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} |
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|
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|
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/** |
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* timed await returns after countDown to zero |
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*/ |
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public void testTimedAwait() { |
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final CountDownLatch l = new CountDownLatch(2); |
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|
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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try { |
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threadAssertTrue(l.getCount() > 0); |
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threadAssertTrue(l.await(SMALL_DELAY_MS, TimeUnit.MILLISECONDS)); |
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} catch(InterruptedException e){ |
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threadUnexpectedException(); |
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} |
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} |
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}); |
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t.start(); |
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try { |
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assertEquals(l.getCount(), 2); |
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Thread.sleep(SHORT_DELAY_MS); |
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l.countDown(); |
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assertEquals(l.getCount(), 1); |
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l.countDown(); |
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assertEquals(l.getCount(), 0); |
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t.join(); |
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} catch (InterruptedException e){ |
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unexpectedException(); |
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} |
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} |
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|
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/** |
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* await throws IE if interrupted before counted down |
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*/ |
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public void testAwait_InterruptedException() { |
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final CountDownLatch l = new CountDownLatch(1); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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try { |
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threadAssertTrue(l.getCount() > 0); |
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l.await(); |
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threadShouldThrow(); |
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} catch(InterruptedException success){} |
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} |
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}); |
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t.start(); |
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try { |
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assertEquals(l.getCount(), 1); |
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t.interrupt(); |
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t.join(); |
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} catch (InterruptedException e){ |
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unexpectedException(); |
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} |
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} |
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|
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/** |
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* timed await throws IE if interrupted before counted down |
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*/ |
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public void testTimedAwait_InterruptedException() { |
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final CountDownLatch l = new CountDownLatch(1); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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try { |
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threadAssertTrue(l.getCount() > 0); |
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l.await(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
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threadShouldThrow(); |
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} catch(InterruptedException success){} |
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} |
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}); |
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t.start(); |
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try { |
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Thread.sleep(SHORT_DELAY_MS); |
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assertEquals(l.getCount(), 1); |
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t.interrupt(); |
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t.join(); |
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} catch (InterruptedException e){ |
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unexpectedException(); |
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} |
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} |
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|
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/** |
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* timed await times out if not counted down before timeout |
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*/ |
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public void testAwaitTimeout() { |
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final CountDownLatch l = new CountDownLatch(1); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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try { |
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threadAssertTrue(l.getCount() > 0); |
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threadAssertFalse(l.await(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
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threadAssertTrue(l.getCount() > 0); |
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} catch(InterruptedException ie){ |
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threadUnexpectedException(); |
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} |
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} |
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}); |
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t.start(); |
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try { |
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assertEquals(l.getCount(), 1); |
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t.join(); |
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} catch (InterruptedException e){ |
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unexpectedException(); |
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} |
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} |
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|
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} |
