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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.ArrayBlockingQueue; |
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import java.util.concurrent.Callable; |
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import java.util.concurrent.CompletionService; |
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import java.util.concurrent.CountDownLatch; |
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import java.util.concurrent.ExecutionException; |
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import java.util.concurrent.ExecutorCompletionService; |
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import java.util.concurrent.ExecutorService; |
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import java.util.concurrent.Future; |
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import java.util.concurrent.FutureTask; |
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import java.util.concurrent.RunnableFuture; |
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import java.util.concurrent.ThreadPoolExecutor; |
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import java.util.concurrent.TimeUnit; |
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import java.util.concurrent.atomic.AtomicBoolean; |
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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 ExecutorCompletionServiceTest extends JSR166TestCase { |
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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(ExecutorCompletionServiceTest.class); |
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} |
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|
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/** |
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* new ExecutorCompletionService(null) throws NullPointerException |
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*/ |
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public void testConstructorNPE() { |
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try { |
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new ExecutorCompletionService<Item>(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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* new ExecutorCompletionService(e, null) throws NullPointerException |
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*/ |
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public void testConstructorNPE2() { |
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try { |
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new ExecutorCompletionService<Item>(cachedThreadPool, 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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* ecs.submit(null) throws NullPointerException |
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*/ |
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public void testSubmitNullCallable() { |
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CompletionService<Item> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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try { |
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cs.submit((Callable<Item>) 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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* ecs.submit(null, val) throws NullPointerException |
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*/ |
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public void testSubmitNullRunnable() { |
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CompletionService<Boolean> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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try { |
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cs.submit((Runnable) 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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* A taken submitted task is completed |
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*/ |
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public void testTake() throws Exception { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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cs.submit(new StringTask()); |
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Future<?> f = cs.take(); |
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assertTrue(f.isDone()); |
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assertSame(TEST_STRING, f.get()); |
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} |
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|
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/** |
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* Take returns the same future object returned by submit |
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*/ |
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public void testTake2() throws InterruptedException { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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Future<?> f1 = cs.submit(new StringTask()); |
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Future<?> f2 = cs.take(); |
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assertSame(f1, f2); |
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} |
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|
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/** |
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* poll returns non-null when the returned task is completed |
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*/ |
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public void testPoll1() throws Exception { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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assertNull(cs.poll()); |
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cs.submit(new StringTask()); |
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|
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long startTime = System.nanoTime(); |
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Future<?> f; |
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while ((f = cs.poll()) == null) { |
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if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
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fail("timed out"); |
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Thread.yield(); |
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} |
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assertTrue(f.isDone()); |
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assertSame(TEST_STRING, f.get()); |
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} |
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|
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/** |
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* timed poll returns non-null when the returned task is completed |
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*/ |
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public void testPoll2() throws Exception { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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assertNull(cs.poll()); |
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cs.submit(new StringTask()); |
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|
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long startTime = System.nanoTime(); |
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Future<?> f; |
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while ((f = cs.poll(timeoutMillis(), MILLISECONDS)) == null) { |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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if (millisElapsedSince(startTime) > LONG_DELAY_MS) |
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fail("timed out"); |
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Thread.yield(); |
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} |
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assertTrue(f.isDone()); |
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assertSame(TEST_STRING, f.get()); |
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} |
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|
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/** |
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* poll returns null before the returned task is completed |
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*/ |
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public void testPollReturnsNullBeforeCompletion() throws Exception { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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final CountDownLatch proceed = new CountDownLatch(1); |
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cs.submit(new Callable<String>() { public String call() throws Exception { |
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await(proceed); |
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return TEST_STRING; |
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}}); |
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assertNull(cs.poll()); |
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assertNull(cs.poll(0L, MILLISECONDS)); |
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assertNull(cs.poll(Long.MIN_VALUE, MILLISECONDS)); |
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long startTime = System.nanoTime(); |
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assertNull(cs.poll(timeoutMillis(), MILLISECONDS)); |
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assertTrue(millisElapsedSince(startTime) >= timeoutMillis()); |
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proceed.countDown(); |
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assertSame(TEST_STRING, cs.take().get()); |
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} |
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|
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/** |
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* successful and failed tasks are both returned |
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*/ |
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public void testTaskAssortment() throws Exception { |
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CompletionService<String> cs = new ExecutorCompletionService<>(cachedThreadPool); |
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ArithmeticException ex = new ArithmeticException(); |
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final int rounds = 2; |
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for (int i = rounds; i--> 0; ) { |
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cs.submit(new StringTask()); |
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cs.submit(callableThrowing(ex)); |
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cs.submit(runnableThrowing(ex), null); |
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} |
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int normalCompletions = 0; |
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int exceptionalCompletions = 0; |
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for (int i = 3 * rounds; i--> 0; ) { |
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try { |
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assertSame(TEST_STRING, cs.take().get()); |
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normalCompletions++; |
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} catch (ExecutionException expected) { |
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assertSame(ex, expected.getCause()); |
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exceptionalCompletions++; |
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} |
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} |
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assertEquals(1 * rounds, normalCompletions); |
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assertEquals(2 * rounds, exceptionalCompletions); |
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assertNull(cs.poll()); |
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} |
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|
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/** |
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* Submitting to underlying AES that overrides newTaskFor(Callable) |
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* returns and eventually runs Future returned by newTaskFor. |
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*/ |
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public void testNewTaskForCallable() throws InterruptedException { |
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final AtomicBoolean done = new AtomicBoolean(false); |
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class MyCallableFuture<V> extends FutureTask<V> { |
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MyCallableFuture(Callable<V> c) { super(c); } |
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@Override protected void done() { done.set(true); } |
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} |
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final ExecutorService e = |
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new ThreadPoolExecutor(1, 1, |
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30L, TimeUnit.SECONDS, |
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new ArrayBlockingQueue<Runnable>(1)) { |
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protected <T> RunnableFuture<T> newTaskFor(Callable<T> c) { |
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return new MyCallableFuture<T>(c); |
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}}; |
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CompletionService<String> cs = new ExecutorCompletionService<>(e); |
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try (PoolCleaner cleaner = cleaner(e)) { |
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assertNull(cs.poll()); |
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Callable<String> c = new StringTask(); |
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Future<?> f1 = cs.submit(c); |
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assertTrue("submit must return MyCallableFuture", |
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f1 instanceof MyCallableFuture); |
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Future<?> f2 = cs.take(); |
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assertSame("submit and take must return same objects", f1, f2); |
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assertTrue("completed task must have set done", done.get()); |
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} |
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} |
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|
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/** |
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* Submitting to underlying AES that overrides newTaskFor(Runnable,T) |
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* returns and eventually runs Future returned by newTaskFor. |
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*/ |
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public void testNewTaskForRunnable() throws InterruptedException { |
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final AtomicBoolean done = new AtomicBoolean(false); |
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class MyRunnableFuture<V> extends FutureTask<V> { |
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MyRunnableFuture(Runnable t, V r) { super(t, r); } |
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@Override protected void done() { done.set(true); } |
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} |
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final ExecutorService e = |
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new ThreadPoolExecutor(1, 1, |
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30L, TimeUnit.SECONDS, |
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new ArrayBlockingQueue<Runnable>(1)) { |
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protected <T> RunnableFuture<T> newTaskFor(Runnable t, T r) { |
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return new MyRunnableFuture<T>(t, r); |
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}}; |
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CompletionService<String> cs = new ExecutorCompletionService<>(e); |
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try (PoolCleaner cleaner = cleaner(e)) { |
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assertNull(cs.poll()); |
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Runnable r = new NoOpRunnable(); |
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Future<?> f1 = cs.submit(r, null); |
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assertTrue("submit must return MyRunnableFuture", |
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f1 instanceof MyRunnableFuture); |
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Future<?> f2 = cs.take(); |
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assertSame("submit and take must return same objects", f1, f2); |
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assertTrue("completed task must have set done", done.get()); |
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} |
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} |
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|
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} |