1 /* 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 */ 22 23 /* 24 * This file is available under and governed by the GNU General Public 25 * License version 2 only, as published by the Free Software Foundation. 26 * However, the following notice accompanied the original version of this 27 * file: 28 * 29 * Written by Martin Buchholz with assistance from members of JCP 30 * JSR-166 Expert Group and released to the public domain, as 31 * explained at http://creativecommons.org/publicdomain/zero/1.0/ 32 */ 33 34 /* 35 * @test 36 * @bug 8073704 37 * @summary Checks that once isDone() returns true, 38 * get() never throws InterruptedException or TimeoutException 39 * @library /test/lib 40 */ 41 42 import static java.util.concurrent.TimeUnit.MILLISECONDS; 43 44 import java.util.ArrayList; 45 import java.util.concurrent.Callable; 46 import java.util.concurrent.CountDownLatch; 47 import java.util.concurrent.ExecutorService; 48 import java.util.concurrent.Executors; 49 import java.util.concurrent.Future; 50 import java.util.concurrent.FutureTask; 51 import java.util.concurrent.ThreadLocalRandom; 52 import java.util.concurrent.TimeUnit; 53 import java.util.concurrent.atomic.AtomicBoolean; 54 import java.util.concurrent.atomic.AtomicReference; 55 import jdk.test.lib.Utils; 56 57 public class DoneMeansDone { 58 static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000); 59 main(String[] args)60 public static void main(String[] args) throws Throwable { 61 final int iters = 1000; 62 final int nThreads = 2; 63 final AtomicBoolean done = new AtomicBoolean(false); 64 final AtomicReference<FutureTask<Boolean>> a = new AtomicReference<>(); 65 final CountDownLatch threadsStarted = new CountDownLatch(nThreads); 66 final Callable<Boolean> alwaysTrue = new Callable<>() { 67 public Boolean call() { 68 return true; 69 }}; 70 71 final Runnable observer = new Runnable() { public void run() { 72 threadsStarted.countDown(); 73 final ThreadLocalRandom rnd = ThreadLocalRandom.current(); 74 try { 75 for (FutureTask<Boolean> f; !done.get();) { 76 f = a.get(); 77 if (f != null) { 78 do {} while (!f.isDone()); 79 Thread.currentThread().interrupt(); 80 if (!(rnd.nextBoolean() 81 ? f.get() 82 : f.get(-1L, TimeUnit.DAYS))) 83 throw new AssertionError(); 84 } 85 } 86 } catch (Exception t) { throw new AssertionError(t); } 87 }}; 88 89 final ArrayList<Future<?>> futures = new ArrayList<>(nThreads); 90 final ExecutorService pool = Executors.newCachedThreadPool(); 91 for (int i = 0; i < nThreads; i++) 92 futures.add(pool.submit(observer)); 93 threadsStarted.await(); 94 for (int i = 0; i < iters; i++) { 95 FutureTask<Boolean> f = new FutureTask<>(alwaysTrue); 96 a.set(f); 97 f.run(); 98 } 99 done.set(true); 100 pool.shutdown(); 101 if (!pool.awaitTermination(LONG_DELAY_MS, MILLISECONDS)) 102 throw new AssertionError(); 103 for (Future<?> future : futures) 104 future.get(); 105 } 106 } 107