/* * Copyright (c) 2021, 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. */ /* * @test * @bug 8274349 * @run main/othervm -XX:ActiveProcessorCount=1 Uniprocessor * @summary Check the default FJ pool has a reasonable default parallelism * level in a uniprocessor environment. */ import java.util.concurrent.CountDownLatch; import java.util.concurrent.ForkJoinPool; public class Uniprocessor { static volatile boolean done = false; public static void main(String[] args) throws InterruptedException { // If the default parallelism were zero then this task would not // complete and the test will timeout. CountDownLatch ran = new CountDownLatch(1); ForkJoinPool.commonPool().submit(() -> ran.countDown()); ran.await(); } }