/*

 * 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.

 *

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 */

/*

 * @test

 * @bug 6571733 6460501

 * @summary Check that regaining a read lock succeeds after a write

 *          lock attempt times out

 */

import java.util.concurrent.locks.*;

import java.util.concurrent.*;

public class Bug6571733 {

    void test(String[] args) throws Throwable {

        test(true);

        test(false);

    }

    void test(boolean fairness) throws Throwable {

        final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fairness);

        // obtain read lock

        lock.readLock().lock();

        Thread thread = new Thread() { public void run() {

            try {

                check(! lock.writeLock().tryLock(0, TimeUnit.DAYS));

                lock.readLock().lock();

                lock.readLock().unlock();

            } catch (Throwable t) { unexpected(t); }}};

        thread.start();

        thread.join();

    }

    //--------------------- Infrastructure ---------------------------

    volatile int passed = 0, failed = 0;

    void pass() {passed++;}

    void fail() {failed++; Thread.dumpStack();}

    void fail(String msg) {System.err.println(msg); fail();}

    void unexpected(Throwable t) {failed++; t.printStackTrace();}

    void check(boolean cond) {if (cond) pass(); else fail();}

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

        new Bug6571733().instanceMain(args);}

    void instanceMain(String[] args) throws Throwable {

        try {test(args);} catch (Throwable t) {unexpected(t);}

        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

        if (failed > 0) throw new AssertionError("Some tests failed");}

}