| 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 |
*/ |
| 8 |
|
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import junit.framework.*; |
| 10 |
import java.util.concurrent.Callable; |
| 11 |
import java.util.concurrent.CancellationException; |
| 12 |
import java.util.concurrent.CountDownLatch; |
| 13 |
import java.util.concurrent.ExecutionException; |
| 14 |
import java.util.concurrent.Future; |
| 15 |
import java.util.concurrent.FutureTask; |
| 16 |
import java.util.concurrent.TimeoutException; |
| 17 |
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
| 18 |
import static java.util.concurrent.TimeUnit.SECONDS; |
| 19 |
import java.util.*; |
| 20 |
|
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public class FutureTaskTest extends JSR166TestCase { |
| 22 |
|
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public static void main(String[] args) { |
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junit.textui.TestRunner.run(suite()); |
| 25 |
} |
| 26 |
public static Test suite() { |
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return new TestSuite(FutureTaskTest.class); |
| 28 |
} |
| 29 |
|
| 30 |
void checkNotDone(Future<?> f) { |
| 31 |
assertFalse(f.isDone()); |
| 32 |
assertFalse(f.isCancelled()); |
| 33 |
} |
| 34 |
|
| 35 |
<T> void checkCompletedNormally(Future<T> f, T expected) { |
| 36 |
assertTrue(f.isDone()); |
| 37 |
assertFalse(f.isCancelled()); |
| 38 |
|
| 39 |
try { |
| 40 |
assertSame(expected, f.get()); |
| 41 |
} catch (Throwable fail) { threadUnexpectedException(fail); } |
| 42 |
try { |
| 43 |
assertSame(expected, f.get(5L, SECONDS)); |
| 44 |
} catch (Throwable fail) { threadUnexpectedException(fail); } |
| 45 |
|
| 46 |
assertFalse(f.cancel(false)); |
| 47 |
assertFalse(f.cancel(true)); |
| 48 |
} |
| 49 |
|
| 50 |
void checkCancelled(Future<?> f) { |
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assertTrue(f.isDone()); |
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assertTrue(f.isCancelled()); |
| 53 |
|
| 54 |
try { |
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f.get(); |
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shouldThrow(); |
| 57 |
} catch (CancellationException success) { |
| 58 |
} catch (Throwable fail) { threadUnexpectedException(fail); } |
| 59 |
|
| 60 |
try { |
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f.get(5L, SECONDS); |
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shouldThrow(); |
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} catch (CancellationException success) { |
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} catch (Throwable fail) { threadUnexpectedException(fail); } |
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|
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assertFalse(f.cancel(false)); |
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assertFalse(f.cancel(true)); |
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} |
| 69 |
|
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void checkCompletedAbnormally(Future<?> f, Throwable t) { |
| 71 |
assertTrue(f.isDone()); |
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assertFalse(f.isCancelled()); |
| 73 |
|
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try { |
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f.get(); |
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shouldThrow(); |
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} catch (ExecutionException success) { |
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assertSame(t, success.getCause()); |
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} catch (Throwable fail) { threadUnexpectedException(fail); } |
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|
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try { |
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f.get(5L, SECONDS); |
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shouldThrow(); |
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} catch (ExecutionException success) { |
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assertSame(t, success.getCause()); |
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} catch (Throwable fail) { threadUnexpectedException(fail); } |
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|
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assertFalse(f.cancel(false)); |
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assertFalse(f.cancel(true)); |
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} |
| 91 |
|
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/** |
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* Subclass to expose protected methods |
| 94 |
*/ |
| 95 |
static class PublicFutureTask extends FutureTask { |
| 96 |
public PublicFutureTask(Callable r) { super(r); } |
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public boolean runAndReset() { return super.runAndReset(); } |
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public void set(Object x) { super.set(x); } |
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public void setException(Throwable t) { super.setException(t); } |
| 100 |
} |
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|
| 102 |
/** |
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* Creating a future with a null callable throws NPE |
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*/ |
| 105 |
public void testConstructor() { |
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try { |
| 107 |
FutureTask task = new FutureTask(null); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* creating a future with null runnable fails |
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*/ |
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public void testConstructor2() { |
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try { |
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FutureTask task = new FutureTask(null, Boolean.TRUE); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* isDone is true when a task completes |
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*/ |
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public void testIsDone() { |
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FutureTask task = new FutureTask(new NoOpCallable()); |
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task.run(); |
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assertTrue(task.isDone()); |
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checkCompletedNormally(task, Boolean.TRUE); |
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} |
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|
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/** |
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* runAndReset of a non-cancelled task succeeds |
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*/ |
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public void testRunAndReset() { |
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PublicFutureTask task = new PublicFutureTask(new NoOpCallable()); |
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assertTrue(task.runAndReset()); |
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checkNotDone(task); |
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} |
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|
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/** |
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* runAndReset after cancellation fails |
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*/ |
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public void testResetAfterCancel() { |
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PublicFutureTask task = new PublicFutureTask(new NoOpCallable()); |
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assertTrue(task.cancel(false)); |
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assertFalse(task.runAndReset()); |
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checkCancelled(task); |
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} |
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|
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|
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/** |
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* setting value causes get to return it |
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*/ |
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public void testSet() throws Exception { |
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PublicFutureTask task = new PublicFutureTask(new NoOpCallable()); |
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task.set(one); |
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assertSame(task.get(), one); |
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checkCompletedNormally(task, one); |
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} |
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|
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/** |
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* setException causes get to throw ExecutionException |
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*/ |
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public void testSetException() throws Exception { |
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Exception nse = new NoSuchElementException(); |
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PublicFutureTask task = new PublicFutureTask(new NoOpCallable()); |
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task.setException(nse); |
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try { |
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Object x = task.get(); |
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shouldThrow(); |
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} catch (ExecutionException success) { |
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assertSame(success.getCause(), nse); |
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checkCompletedAbnormally(task, nse); |
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} |
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} |
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|
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/** |
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* Cancelling before running succeeds |
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*/ |
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public void testCancelBeforeRun() { |
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FutureTask task = new FutureTask(new NoOpCallable()); |
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assertTrue(task.cancel(false)); |
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task.run(); |
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checkCancelled(task); |
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} |
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|
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/** |
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* Cancel(true) before run succeeds |
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*/ |
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public void testCancelBeforeRun2() { |
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FutureTask task = new FutureTask(new NoOpCallable()); |
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assertTrue(task.cancel(true)); |
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task.run(); |
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checkCancelled(task); |
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} |
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|
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/** |
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* cancel of a completed task fails |
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*/ |
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public void testCancelAfterRun() { |
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FutureTask task = new FutureTask(new NoOpCallable()); |
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task.run(); |
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assertFalse(task.cancel(false)); |
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checkCompletedNormally(task, Boolean.TRUE); |
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} |
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|
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/** |
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* cancel(true) interrupts a running task |
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*/ |
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public void testCancelInterrupt() throws InterruptedException { |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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final FutureTask task = |
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new FutureTask(new CheckedCallable<Object>() { |
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public Object realCall() { |
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threadStarted.countDown(); |
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long t0 = System.nanoTime(); |
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for (;;) { |
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if (Thread.interrupted()) |
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return Boolean.TRUE; |
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if (millisElapsedSince(t0) > MEDIUM_DELAY_MS) |
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fail("interrupt not delivered"); |
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Thread.yield(); |
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} |
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}}); |
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|
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Thread t = newStartedThread(task); |
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threadStarted.await(); |
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assertTrue(task.cancel(true)); |
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checkCancelled(task); |
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awaitTermination(t, MEDIUM_DELAY_MS); |
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checkCancelled(task); |
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} |
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|
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/** |
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* cancel(false) does not interrupt a running task |
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*/ |
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public void testCancelNoInterrupt() throws InterruptedException { |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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final CountDownLatch cancelled = new CountDownLatch(1); |
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final FutureTask<Boolean> task = |
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new FutureTask<Boolean>(new CheckedCallable<Boolean>() { |
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public Boolean realCall() throws InterruptedException { |
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threadStarted.countDown(); |
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cancelled.await(MEDIUM_DELAY_MS, MILLISECONDS); |
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assertFalse(Thread.interrupted()); |
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return Boolean.TRUE; |
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}}); |
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|
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Thread t = newStartedThread(task); |
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threadStarted.await(); |
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assertTrue(task.cancel(false)); |
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checkCancelled(task); |
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cancelled.countDown(); |
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awaitTermination(t, MEDIUM_DELAY_MS); |
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checkCancelled(task); |
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} |
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|
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/** |
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* run in one thread causes get in another thread to retrieve value |
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*/ |
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public void testGetRun() throws InterruptedException { |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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|
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final FutureTask task = |
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new FutureTask(new CheckedCallable<Object>() { |
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public Object realCall() throws InterruptedException { |
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return Boolean.TRUE; |
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}}); |
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|
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws Exception { |
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threadStarted.countDown(); |
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assertSame(Boolean.TRUE, task.get()); |
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}}); |
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|
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threadStarted.await(); |
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checkNotDone(task); |
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assertTrue(t.isAlive()); |
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task.run(); |
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checkCompletedNormally(task, Boolean.TRUE); |
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awaitTermination(t, MEDIUM_DELAY_MS); |
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} |
| 284 |
|
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/** |
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* set in one thread causes get in another thread to retrieve value |
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*/ |
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public void testGetSet() throws InterruptedException { |
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final CountDownLatch threadStarted = new CountDownLatch(1); |
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|
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final PublicFutureTask task = |
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new PublicFutureTask(new CheckedCallable<Object>() { |
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public Object realCall() throws InterruptedException { |
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return Boolean.TRUE; |
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}}); |
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|
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Thread t = newStartedThread(new CheckedRunnable() { |
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public void realRun() throws Exception { |
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threadStarted.countDown(); |
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assertSame(Boolean.FALSE, task.get()); |
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}}); |
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|
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threadStarted.await(); |
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checkNotDone(task); |
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assertTrue(t.isAlive()); |
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task.set(Boolean.FALSE); |
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checkCompletedNormally(task, Boolean.FALSE); |
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awaitTermination(t, MEDIUM_DELAY_MS); |
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} |
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|
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/** |
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* run in one thread causes timed get in another thread to retrieve value |
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*/ |
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public void testTimedGetRun() throws InterruptedException { |
| 315 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
| 316 |
|
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final FutureTask task = |
| 318 |
new FutureTask(new CheckedCallable<Object>() { |
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public Object realCall() throws InterruptedException { |
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return Boolean.TRUE; |
| 321 |
}}); |
| 322 |
|
| 323 |
Thread t = newStartedThread(new CheckedRunnable() { |
| 324 |
public void realRun() throws Exception { |
| 325 |
threadStarted.countDown(); |
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assertSame(Boolean.TRUE, |
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task.get(MEDIUM_DELAY_MS, MILLISECONDS)); |
| 328 |
}}); |
| 329 |
|
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threadStarted.await(); |
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checkNotDone(task); |
| 332 |
assertTrue(t.isAlive()); |
| 333 |
task.run(); |
| 334 |
checkCompletedNormally(task, Boolean.TRUE); |
| 335 |
awaitTermination(t, MEDIUM_DELAY_MS); |
| 336 |
} |
| 337 |
|
| 338 |
/** |
| 339 |
* set in one thread causes timed get in another thread to retrieve value |
| 340 |
*/ |
| 341 |
public void testTimedGetSet() throws InterruptedException { |
| 342 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
| 343 |
|
| 344 |
final PublicFutureTask task = |
| 345 |
new PublicFutureTask(new CheckedCallable<Object>() { |
| 346 |
public Object realCall() throws InterruptedException { |
| 347 |
return Boolean.TRUE; |
| 348 |
}}); |
| 349 |
|
| 350 |
Thread t = newStartedThread(new CheckedRunnable() { |
| 351 |
public void realRun() throws Exception { |
| 352 |
threadStarted.countDown(); |
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assertSame(Boolean.FALSE, |
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task.get(MEDIUM_DELAY_MS, MILLISECONDS)); |
| 355 |
}}); |
| 356 |
|
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threadStarted.await(); |
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checkNotDone(task); |
| 359 |
assertTrue(t.isAlive()); |
| 360 |
task.set(Boolean.FALSE); |
| 361 |
checkCompletedNormally(task, Boolean.FALSE); |
| 362 |
awaitTermination(t, MEDIUM_DELAY_MS); |
| 363 |
} |
| 364 |
|
| 365 |
/** |
| 366 |
* Cancelling a task causes timed get in another thread to throw |
| 367 |
* CancellationException |
| 368 |
*/ |
| 369 |
public void testTimedGet_Cancellation() throws InterruptedException { |
| 370 |
final CountDownLatch threadStarted = new CountDownLatch(2); |
| 371 |
final FutureTask task = |
| 372 |
new FutureTask(new CheckedInterruptedCallable<Object>() { |
| 373 |
public Object realCall() throws InterruptedException { |
| 374 |
threadStarted.countDown(); |
| 375 |
delay(LONG_DELAY_MS); |
| 376 |
return Boolean.TRUE; |
| 377 |
}}); |
| 378 |
|
| 379 |
Thread t1 = new ThreadShouldThrow(CancellationException.class) { |
| 380 |
public void realRun() throws Exception { |
| 381 |
threadStarted.countDown(); |
| 382 |
task.get(MEDIUM_DELAY_MS, MILLISECONDS); |
| 383 |
}}; |
| 384 |
Thread t2 = new Thread(task); |
| 385 |
t1.start(); |
| 386 |
t2.start(); |
| 387 |
threadStarted.await(); |
| 388 |
task.cancel(true); |
| 389 |
awaitTermination(t1, MEDIUM_DELAY_MS); |
| 390 |
awaitTermination(t2, MEDIUM_DELAY_MS); |
| 391 |
checkCancelled(task); |
| 392 |
} |
| 393 |
|
| 394 |
/** |
| 395 |
* Cancelling a task causes get in another thread to throw |
| 396 |
* CancellationException |
| 397 |
*/ |
| 398 |
public void testGet_Cancellation() throws InterruptedException { |
| 399 |
final CountDownLatch threadStarted = new CountDownLatch(2); |
| 400 |
final FutureTask task = |
| 401 |
new FutureTask(new CheckedInterruptedCallable<Object>() { |
| 402 |
public Object realCall() throws InterruptedException { |
| 403 |
threadStarted.countDown(); |
| 404 |
delay(LONG_DELAY_MS); |
| 405 |
return Boolean.TRUE; |
| 406 |
}}); |
| 407 |
|
| 408 |
Thread t1 = new ThreadShouldThrow(CancellationException.class) { |
| 409 |
public void realRun() throws Exception { |
| 410 |
threadStarted.countDown(); |
| 411 |
task.get(); |
| 412 |
}}; |
| 413 |
Thread t2 = new Thread(task); |
| 414 |
t1.start(); |
| 415 |
t2.start(); |
| 416 |
threadStarted.await(); |
| 417 |
task.cancel(true); |
| 418 |
awaitTermination(t1, MEDIUM_DELAY_MS); |
| 419 |
awaitTermination(t2, MEDIUM_DELAY_MS); |
| 420 |
checkCancelled(task); |
| 421 |
} |
| 422 |
|
| 423 |
|
| 424 |
/** |
| 425 |
* A runtime exception in task causes get to throw ExecutionException |
| 426 |
*/ |
| 427 |
public void testGet_ExecutionException() throws InterruptedException { |
| 428 |
final FutureTask task = new FutureTask(new Callable() { |
| 429 |
public Object call() { |
| 430 |
return 5/0; |
| 431 |
}}); |
| 432 |
|
| 433 |
task.run(); |
| 434 |
try { |
| 435 |
task.get(); |
| 436 |
shouldThrow(); |
| 437 |
} catch (ExecutionException success) { |
| 438 |
assertTrue(success.getCause() instanceof ArithmeticException); |
| 439 |
checkCompletedAbnormally(task, success.getCause()); |
| 440 |
} |
| 441 |
} |
| 442 |
|
| 443 |
/** |
| 444 |
* A runtime exception in task causes timed get to throw ExecutionException |
| 445 |
*/ |
| 446 |
public void testTimedGet_ExecutionException2() throws Exception { |
| 447 |
final FutureTask task = new FutureTask(new Callable() { |
| 448 |
public Object call() { |
| 449 |
return 5/0; |
| 450 |
}}); |
| 451 |
|
| 452 |
task.run(); |
| 453 |
try { |
| 454 |
task.get(SHORT_DELAY_MS, MILLISECONDS); |
| 455 |
shouldThrow(); |
| 456 |
} catch (ExecutionException success) { |
| 457 |
assertTrue(success.getCause() instanceof ArithmeticException); |
| 458 |
checkCompletedAbnormally(task, success.getCause()); |
| 459 |
} |
| 460 |
} |
| 461 |
|
| 462 |
|
| 463 |
/** |
| 464 |
* Interrupting a waiting get causes it to throw InterruptedException |
| 465 |
*/ |
| 466 |
public void testGet_InterruptedException() throws InterruptedException { |
| 467 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
| 468 |
final FutureTask task = new FutureTask(new NoOpCallable()); |
| 469 |
Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
| 470 |
public void realRun() throws Exception { |
| 471 |
threadStarted.countDown(); |
| 472 |
task.get(); |
| 473 |
}}); |
| 474 |
|
| 475 |
threadStarted.await(); |
| 476 |
t.interrupt(); |
| 477 |
awaitTermination(t, MEDIUM_DELAY_MS); |
| 478 |
checkNotDone(task); |
| 479 |
} |
| 480 |
|
| 481 |
/** |
| 482 |
* Interrupting a waiting timed get causes it to throw InterruptedException |
| 483 |
*/ |
| 484 |
public void testTimedGet_InterruptedException2() throws InterruptedException { |
| 485 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
| 486 |
final FutureTask task = new FutureTask(new NoOpCallable()); |
| 487 |
Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
| 488 |
public void realRun() throws Exception { |
| 489 |
threadStarted.countDown(); |
| 490 |
task.get(LONG_DELAY_MS, MILLISECONDS); |
| 491 |
}}); |
| 492 |
|
| 493 |
threadStarted.await(); |
| 494 |
t.interrupt(); |
| 495 |
awaitTermination(t, MEDIUM_DELAY_MS); |
| 496 |
checkNotDone(task); |
| 497 |
} |
| 498 |
|
| 499 |
/** |
| 500 |
* A timed out timed get throws TimeoutException |
| 501 |
*/ |
| 502 |
public void testGet_TimeoutException() throws Exception { |
| 503 |
try { |
| 504 |
FutureTask task = new FutureTask(new NoOpCallable()); |
| 505 |
task.get(1, MILLISECONDS); |
| 506 |
shouldThrow(); |
| 507 |
} catch (TimeoutException success) {} |
| 508 |
} |
| 509 |
|
| 510 |
} |
