/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

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 * published by the Free Software Foundation.

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 * 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).

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 * 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.

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/*

 * @test

 * @bug     4892507

 * @summary Basic Test for the following reset methods:

 *          - ThreadMXBean.findMonitorDeadlockedThreads()

 * @author  Mandy Chung

 *

 * @build MonitorDeadlock

 * @build ThreadDump

 * @run main FindMonitorDeadlock

 */

import java.lang.management.*;

import java.util.*;

public class FindMonitorDeadlock {

    public static void main(String[] argv) {

        // create deadlocked threads

        MonitorDeadlock md = new MonitorDeadlock();

        // No deadlock

        ThreadMXBean mbean = ManagementFactory.getThreadMXBean();

        long[] threads = mbean.findMonitorDeadlockedThreads();

        if (threads != null) {

            throw new RuntimeException("TEST FAILED: Should return null.");

        }

        // Let the threads to proceed

        md.goDeadlock();

        // wait until the deadlock is ready

        md.waitUntilDeadlock();

        // Find Deadlock

        threads = mbean.findMonitorDeadlockedThreads();

        if (threads == null) {

            ThreadDump.dumpStacks();

            throw new RuntimeException("TEST FAILED: Deadlock not detected.");

        }

        // Print Deadlock stack trace

        System.out.println("Found threads that are in deadlock:-");

        ThreadInfo[] infos = mbean.getThreadInfo(threads, Integer.MAX_VALUE);

        for (int i = 0; i < infos.length; i++) {

            ThreadDump.printThreadInfo(infos[i]);

        }

        md.checkResult(threads);

        System.out.println("Test passed");

    }

}