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/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Martin Buchholz 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/
*/
/*
* @test
* @bug 8073704
* @summary Checks that once isDone() returns true,
* get() never throws InterruptedException or TimeoutException
* @library /lib/testlibrary/
*/
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import java.util.ArrayList;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;
import jdk.testlibrary.Utils;
public class DoneMeansDone {
static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);
public static void main(String[] args) throws Throwable {
final int iters = 1000;
final int nThreads = 2;
final AtomicBoolean done = new AtomicBoolean(false);
final AtomicReference<FutureTask<Boolean>> a = new AtomicReference<>();
final CountDownLatch threadsStarted = new CountDownLatch(nThreads);
final Callable<Boolean> alwaysTrue = new Callable<>() {
public Boolean call() {
return true;
}};
final Runnable observer = new Runnable() { public void run() {
threadsStarted.countDown();
final ThreadLocalRandom rnd = ThreadLocalRandom.current();
try {
for (FutureTask<Boolean> f; !done.get();) {
f = a.get();
if (f != null) {
do {} while (!f.isDone());
Thread.currentThread().interrupt();
if (!(rnd.nextBoolean()
? f.get()
: f.get(-1L, TimeUnit.DAYS)))
throw new AssertionError();
}
}
} catch (Exception t) { throw new AssertionError(t); }
}};
final ArrayList<Future<?>> futures = new ArrayList<>(nThreads);
final ExecutorService pool = Executors.newCachedThreadPool();
for (int i = 0; i < nThreads; i++)
futures.add(pool.submit(observer));
threadsStarted.await();
for (int i = 0; i < iters; i++) {
FutureTask<Boolean> f = new FutureTask<>(alwaysTrue);
a.set(f);
f.run();
}
done.set(true);
pool.shutdown();
if (!pool.awaitTermination(LONG_DELAY_MS, MILLISECONDS))
throw new AssertionError();
for (Future<?> future : futures)
future.get();
}
}
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