/*

 * 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.

 *

 * 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 6318638 6325166 6330307

 * @summary CopyOnWriteArrayList.equals should be thread-safe

 * @author Martin Buchholz

 */

import java.util.*;

import java.util.concurrent.*;

public class EqualsRace {

    private static void realMain(String[] args) throws Throwable {

        final int iterations = 100000;

        final List<Integer> list = new CopyOnWriteArrayList<Integer>();

        final Integer one = Integer.valueOf(1);

        final List<Integer> oneElementList = Arrays.asList(one);

        final Thread t = new CheckedThread() { public void realRun() {

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

                list.add(one);

                list.remove(one);

            }}};

        t.start();

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

            list.equals(oneElementList);

            list.equals(Collections.EMPTY_LIST);

        }

        t.join();

        check(list.size() == 0);

    }

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

    static volatile int passed = 0, failed = 0;

    static void pass() {passed++;}

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

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

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

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

    static void equal(Object x, Object y) {

        if (x == null ? y == null : x.equals(y)) pass();

        else fail(x + " not equal to " + y);}

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

        try {realMain(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");}

    private abstract static class CheckedThread extends Thread {

        public abstract void realRun() throws Throwable;

        public void run() {

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

}