| /* |
| * Copyright (c) 2005, 2015, 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 6337571 |
| * @summary Test if findDeadlockedThreads works for an ownable synchronizer |
| * in shared mode which has no owner when a thread is parked. |
| * @author Mandy Chung |
| * |
| * @run main/othervm SharedSynchronizer |
| */ |
| |
| |
| import java.util.concurrent.*; |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.ThreadMXBean; |
| |
| public class SharedSynchronizer { |
| public static void main(String[] args) throws Exception { |
| MyThread t = new MyThread(); |
| t.setDaemon(true); |
| t.start(); |
| |
| ThreadMXBean tmbean = ManagementFactory.getThreadMXBean(); |
| if (!tmbean.isSynchronizerUsageSupported()) { |
| System.out.println("Monitoring of synchronizer usage not supported") |
| ; |
| return; |
| } |
| |
| long[] result = tmbean.findDeadlockedThreads(); |
| if (result != null) { |
| throw new RuntimeException("TEST FAILED: result should be null"); |
| } |
| } |
| |
| static class MyThread extends Thread { |
| public void run() { |
| FutureTask f = new FutureTask( |
| new Callable() { |
| public Object call() { |
| throw new RuntimeException("should never reach here"); |
| } |
| } |
| ); |
| |
| // A FutureTask uses the AbstractOwnableSynchronizer in a shared |
| // mode (not exclusive mode). When the thread calls f.get(), |
| // it will put to park on the ownable synchronizer that |
| // is not owned by any thread. |
| try { |
| f.get(); |
| } catch (Exception e) { |
| RuntimeException re = new RuntimeException(e.getMessage()); |
| re.initCause(e); |
| throw re; |
| } |
| } |
| } |
| } |