jdk/test/java/util/logging/LoggingDeadlock4.java
author dcubed
Mon, 16 May 2011 12:56:29 -0700
changeset 9699 5dfc211872f4
child 12047 320a714614e9
permissions -rw-r--r--
6977677: 3/2 Deadlock on logging subsystem initialization Summary: Over synchronized Logger.getLogger() deadlocks with LogManager.<clinit>via PlatformLogger Reviewed-by: dsamersoff, never, acorn, mchung

/*
 * Copyright (c) 2011, 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     6977677
 * @summary Deadlock between LogManager.<clinit> and Logger.getLogger()
 * @author  Daniel D. Daugherty
 * @build LoggingDeadlock4
 * @run main/timeout=15 LoggingDeadlock4
 */

import java.awt.Container;
import java.util.concurrent.CountDownLatch;
import java.util.logging.LogManager;
import java.util.logging.Logger;

public class LoggingDeadlock4 {
    private static CountDownLatch barrier      = new CountDownLatch(1);
    private static CountDownLatch lmIsRunning  = new CountDownLatch(1);
    private static CountDownLatch logIsRunning = new CountDownLatch(1);

    public static void main(String[] args) {
        System.out.println("main: LoggingDeadlock4 is starting.");

        // Loading the java.awt.Container class will create a
        // sun.util.logging.PlatformLogger$JavaLogger object
        // that has to be redirected when the LogManager class
        // is initialized. This can cause a deadlock between
        // LogManager.<clinit> and Logger.getLogger().
        try {
            Class.forName("java.awt.Container");
        } catch (ClassNotFoundException cnfe) {
            throw new RuntimeException("Test failed: could not load"
                + " java.awt.Container." + cnfe);
        }

        Thread lmThread = new Thread("LogManagerThread") {
            public void run() {
                // let main know LogManagerThread is running
                lmIsRunning.countDown();

                System.out.println(Thread.currentThread().getName()
                    + ": is running.");

                try {
                    barrier.await();  // wait for race to start
                } catch (InterruptedException e) {
                }

                LogManager manager = LogManager.getLogManager();
            }
        };
        lmThread.start();

        Thread logThread = new Thread("LoggerThread") {
            public void run() {
                // let main know LoggerThread is running
                logIsRunning.countDown();

                System.out.println(Thread.currentThread().getName()
                    + ": is running.");

                try {
                    barrier.await();  // wait for race to start
                } catch (InterruptedException e) {
                }

                Logger foo = Logger.getLogger("foo logger");
            }
        };
        logThread.start();

        try {
            // wait for LogManagerThread and LoggerThread to get going
            lmIsRunning.await();
            logIsRunning.await();
        } catch (InterruptedException e) {
        }

        barrier.countDown();  // start the race

        try {
            lmThread.join();
            logThread.join();
        } catch (InterruptedException ie) {
        }

        System.out.println("main: LoggingDeadlock4 is done.");
    }
}