/*

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

 *

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 * 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.

 *

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 */

/*

 * @test

 * @bug     4994705

 *

 * @summary deadlock in LogManager

 * @author  Serguei Spitsyn / SAP

 *

 * @build    LoggingDeadlock

 * @run  main/timeout=15 LoggingDeadlock

 *

 * There can be a deadlock between two class initializations.

 * It happens if the LogManager.<clinit> and the Logger.<clinit>

 * are invoked concurrently on two different threads.

 * There is a cyclic dependence between the two static initializers:

 *   1. LogManager.<clinit> instantiate the class RootLogger which

 *      is a subclass of the Logger class.

 *      It requires the Logger class initialization to complete.

 *   2. Logger.<clinit> initializes the field "global", so it

 *      it makes a call: Logger.getLogger("global").

 *      Subsequently the LogManager static method getLogManager()

 *      is called which requires the LogManager class

 *      initialization to complete.

 * This cyclic dependence causes a deadlock, so two class

 * initializations are waiting for each other.

 * This is a regression test for this bug.

 */

import java.util.logging.LogManager;

import java.util.logging.Logger;

public class LoggingDeadlock {

    public static void randomDelay() {

        int runs = (int) Math.random() * 1000000;

        int c = 0;

        for (int i = 0; i < runs; ++i) {

            c = c + i;

        }

    }

    public static void main(String[] args) throws InterruptedException{

        Thread t1 = new Thread(new Runnable() {

            public void run() {

                randomDelay();

                // Trigger Logger.<clinit>

                Logger.getAnonymousLogger();

            }

        });

        Thread t2 = new Thread(new Runnable() {

            public void run() {

                randomDelay();

                // Trigger LogManager.<clinit>

                LogManager.getLogManager();

            }

        });

        t1.start();

        t2.start();

        t1.join();

        t2.join();

        System.out.println("\nTest passed");

    }

}