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Diffstat (limited to 'jsr166-tests/src/test/java/jsr166/CountDownLatchTest.java')
| -rw-r--r-- | jsr166-tests/src/test/java/jsr166/CountDownLatchTest.java | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/jsr166-tests/src/test/java/jsr166/CountDownLatchTest.java b/jsr166-tests/src/test/java/jsr166/CountDownLatchTest.java new file mode 100644 index 0000000..bc2aecf --- /dev/null +++ b/jsr166-tests/src/test/java/jsr166/CountDownLatchTest.java @@ -0,0 +1,190 @@ +/* + * Written by Doug Lea with assistance from members of JCP JSR-166 + * Expert Group and released to the public domain, as explained at + * http://creativecommons.org/publicdomain/zero/1.0/ + * Other contributors include Andrew Wright, Jeffrey Hayes, + * Pat Fisher, Mike Judd. + */ + +package jsr166; + +import junit.framework.*; +import java.util.*; +import java.util.concurrent.CountDownLatch; +import static java.util.concurrent.TimeUnit.MILLISECONDS; + +public class CountDownLatchTest extends JSR166TestCase { + + /** + * negative constructor argument throws IAE + */ + public void testConstructor() { + try { + new CountDownLatch(-1); + shouldThrow(); + } catch (IllegalArgumentException success) {} + } + + /** + * getCount returns initial count and decreases after countDown + */ + public void testGetCount() { + final CountDownLatch l = new CountDownLatch(2); + assertEquals(2, l.getCount()); + l.countDown(); + assertEquals(1, l.getCount()); + } + + /** + * countDown decrements count when positive and has no effect when zero + */ + public void testCountDown() { + final CountDownLatch l = new CountDownLatch(1); + assertEquals(1, l.getCount()); + l.countDown(); + assertEquals(0, l.getCount()); + l.countDown(); + assertEquals(0, l.getCount()); + } + + /** + * await returns after countDown to zero, but not before + */ + public void testAwait() { + final CountDownLatch l = new CountDownLatch(2); + final CountDownLatch pleaseCountDown = new CountDownLatch(1); + + Thread t = newStartedThread(new CheckedRunnable() { + public void realRun() throws InterruptedException { + assertEquals(2, l.getCount()); + pleaseCountDown.countDown(); + l.await(); + assertEquals(0, l.getCount()); + }}); + + await(pleaseCountDown); + assertEquals(2, l.getCount()); + l.countDown(); + assertEquals(1, l.getCount()); + assertThreadStaysAlive(t); + l.countDown(); + assertEquals(0, l.getCount()); + awaitTermination(t); + } + + /** + * timed await returns after countDown to zero + */ + public void testTimedAwait() { + final CountDownLatch l = new CountDownLatch(2); + final CountDownLatch pleaseCountDown = new CountDownLatch(1); + + Thread t = newStartedThread(new CheckedRunnable() { + public void realRun() throws InterruptedException { + assertEquals(2, l.getCount()); + pleaseCountDown.countDown(); + assertTrue(l.await(LONG_DELAY_MS, MILLISECONDS)); + assertEquals(0, l.getCount()); + }}); + + await(pleaseCountDown); + assertEquals(2, l.getCount()); + l.countDown(); + assertEquals(1, l.getCount()); + assertThreadStaysAlive(t); + l.countDown(); + assertEquals(0, l.getCount()); + awaitTermination(t); + } + + /** + * await throws IE if interrupted before counted down + */ + public void testAwait_Interruptible() { + final CountDownLatch l = new CountDownLatch(1); + final CountDownLatch pleaseInterrupt = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedRunnable() { + public void realRun() throws InterruptedException { + Thread.currentThread().interrupt(); + try { + l.await(); + shouldThrow(); + } catch (InterruptedException success) {} + assertFalse(Thread.interrupted()); + + pleaseInterrupt.countDown(); + try { + l.await(); + shouldThrow(); + } catch (InterruptedException success) {} + assertFalse(Thread.interrupted()); + + assertEquals(1, l.getCount()); + }}); + + await(pleaseInterrupt); + assertThreadStaysAlive(t); + t.interrupt(); + awaitTermination(t); + } + + /** + * timed await throws IE if interrupted before counted down + */ + public void testTimedAwait_Interruptible() { + final CountDownLatch l = new CountDownLatch(1); + final CountDownLatch pleaseInterrupt = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedRunnable() { + public void realRun() throws InterruptedException { + Thread.currentThread().interrupt(); + try { + l.await(LONG_DELAY_MS, MILLISECONDS); + shouldThrow(); + } catch (InterruptedException success) {} + assertFalse(Thread.interrupted()); + + pleaseInterrupt.countDown(); + try { + l.await(LONG_DELAY_MS, MILLISECONDS); + shouldThrow(); + } catch (InterruptedException success) {} + assertFalse(Thread.interrupted()); + + assertEquals(1, l.getCount()); + }}); + + await(pleaseInterrupt); + assertThreadStaysAlive(t); + t.interrupt(); + awaitTermination(t); + } + + /** + * timed await times out if not counted down before timeout + */ + public void testAwaitTimeout() throws InterruptedException { + final CountDownLatch l = new CountDownLatch(1); + Thread t = newStartedThread(new CheckedRunnable() { + public void realRun() throws InterruptedException { + assertEquals(1, l.getCount()); + assertFalse(l.await(timeoutMillis(), MILLISECONDS)); + assertEquals(1, l.getCount()); + }}); + + awaitTermination(t); + assertEquals(1, l.getCount()); + } + + /** + * toString indicates current count + */ + public void testToString() { + CountDownLatch s = new CountDownLatch(2); + assertTrue(s.toString().contains("Count = 2")); + s.countDown(); + assertTrue(s.toString().contains("Count = 1")); + s.countDown(); + assertTrue(s.toString().contains("Count = 0")); + } + +} |