| /* |
| * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. |
| * 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. |
| */ |
| |
| import org.testng.Assert; |
| import org.testng.annotations.Test; |
| |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.CountDownLatch; |
| |
| /** |
| * @test |
| * @bug 8029164 |
| * @run testng ThenComposeAsyncTest |
| * @run testng/othervm -Djava.util.concurrent.ForkJoinPool.common.parallelism=0 ThenComposeAsyncTest |
| * @summary Test that CompletableFuture.thenCompose works correctly if the |
| * composing task is complete before composition |
| */ |
| @Test |
| public class ThenComposeAsyncTest { |
| |
| public void testThenComposeAsync() throws Exception { |
| // Composing CompletableFuture is complete |
| CompletableFuture<String> cf1 = CompletableFuture.completedFuture("one"); |
| |
| // Composing function returns a CompletableFuture executed asynchronously |
| CountDownLatch cdl = new CountDownLatch(1); |
| CompletableFuture<String> cf2 = cf1.thenCompose(str -> CompletableFuture.supplyAsync(() -> { |
| while (true) { |
| try { |
| cdl.await(); |
| break; |
| } |
| catch (InterruptedException e) { |
| } |
| } |
| return str + ", two"; |
| })); |
| |
| // Ensure returned CompletableFuture completes after call to thenCompose |
| // This guarantees that any premature internal completion will be |
| // detected |
| cdl.countDown(); |
| |
| String val = cf2.get(); |
| Assert.assertNotNull(val); |
| Assert.assertEquals(val, "one, two"); |
| } |
| } |