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/* |
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* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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|
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import org.testng.Assert; |
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import org.testng.annotations.Test; |
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|
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import java.util.concurrent.CompletableFuture; |
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import java.util.concurrent.CountDownLatch; |
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|
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/** |
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* @test |
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* @bug 8029164 |
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* @run testng ThenComposeAsyncTest |
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* @run testng/othervm -Djava.util.concurrent.ForkJoinPool.common.parallelism=0 ThenComposeAsyncTest |
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* @summary Test that CompletableFuture.thenCompose works correctly if the |
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* composing task is complete before composition |
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*/ |
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@Test |
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public class ThenComposeAsyncTest { |
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|
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public void testThenComposeAsync() throws Exception { |
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// Composing CompletableFuture is complete |
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CompletableFuture<String> cf1 = CompletableFuture.completedFuture("one"); |
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|
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// Composing function returns a CompletableFuture executed asynchronously |
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CountDownLatch cdl = new CountDownLatch(1); |
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CompletableFuture<String> cf2 = cf1.thenCompose(str -> CompletableFuture.supplyAsync(() -> { |
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while (true) { |
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try { |
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cdl.await(); |
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break; |
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} |
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catch (InterruptedException e) { |
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} |
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} |
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return str + ", two"; |
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})); |
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|
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// Ensure returned CompletableFuture completes after call to thenCompose |
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// This guarantees that any premature internal completion will be |
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// detected |
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cdl.countDown(); |
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|
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String val = cf2.get(); |
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Assert.assertNotNull(val); |
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Assert.assertEquals(val, "one, two"); |
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} |
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} |
