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 * Copyright (c) 2018, 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.

 */

import java.awt.AWTEvent;

import java.awt.event.InvocationEvent;

import java.lang.reflect.Constructor;

import java.util.concurrent.CountDownLatch;

import java.util.concurrent.atomic.AtomicReference;

import sun.awt.AppContext;

import sun.awt.SunToolkit;

/**

 * @test

 * @bug 8204142

 * @author Sergey Bylokhov

 * @key headful

 * @modules java.desktop/sun.awt

 * @run main/othervm/timeout=30 MultipleContextsUnitTest

 */

public final class MultipleContextsUnitTest {

    private static final int COUNT = 20;

    private static final AppContext[] apps = new AppContext[COUNT];

    private static final CountDownLatch go = new CountDownLatch(1);

    private static final CountDownLatch end = new CountDownLatch(COUNT);

    private static volatile int createSENumber = 0;

    private static volatile int dispatchSENumber = 0;

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

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

            Thread t = testThread(i);

            t.start();

            t.join();

        }

        for (AppContext app : apps) {

            SunToolkit.postEvent(app, new InvocationEvent(new Object(), () -> {

                try {

                    go.await();

                } catch (InterruptedException e) {

                    throw new RuntimeException(e);

                }

            }));

        }

        // eventOne - created first, but posted last

        AWTEvent eventOne = getSequencedEvent();

        {

            // eventTwo and eventThree - posted in the reverse order

            AppContext app = apps[1];

            AWTEvent eventTwo = getSequencedEvent();

            AWTEvent eventThree = getSequencedEvent();

            SunToolkit.postEvent(app, eventThree);

            SunToolkit.postEvent(app, eventTwo);

            SunToolkit.postEvent(app, new InvocationEvent(new Object(), () -> {

                System.err.println(AppContext.getAppContext());

                end.countDown();

            }));

        }

        for (int i = 2; i < apps.length; i++) {

            // eventTwo and eventThree - posted in the correct order

            AppContext app = apps[i];

            AWTEvent eventTwo = getSequencedEvent();

            SunToolkit.postEvent(app, eventTwo);

            AtomicReference<Boolean> called1 = new AtomicReference(false);

            AtomicReference<Boolean> called2 = new AtomicReference(false);

            int num1 = createSENumber;

            SunToolkit.postEvent(app, new InvocationEvent(new Object(), () -> {

                if (dispatchSENumber < num1) {

                    throw new RuntimeException("Dispatched too early");

                }

                called1.set(true);

                if (called2.get()) {

                    throw new RuntimeException("Second event is called before first");

                }

            }));

            AWTEvent eventThree = getSequencedEvent();

            SunToolkit.postEvent(app, eventThree);

            int num2 = createSENumber;

            SunToolkit.postEvent(app, new InvocationEvent(new Object(), () -> {

                if (dispatchSENumber < num2) {

                    throw new RuntimeException("Dispatched too early");

                }

                called2.set(true);

                if (!called1.get()) {

                    throw new RuntimeException("First event is not called before second");

                }

                System.err.println(AppContext.getAppContext());

                end.countDown();

            }));

        }

        // eventOne should flush all EDT

        SunToolkit.postEvent(apps[0], eventOne);

        SunToolkit.postEvent(apps[0], new InvocationEvent(new Object(), () -> {

            System.err.println(AppContext.getAppContext());

            end.countDown();

        }));

        go.countDown();

        System.err.println("Start to wait");

        end.await();

        System.err.println("End to wait");

    }

    private static Thread testThread(int index) {

        final ThreadGroup group = new ThreadGroup("TG " + index);

        return new Thread(group, () -> {

            apps[index] = SunToolkit.createNewAppContext();

        });

    }

    private static AWTEvent getSequencedEvent()

    {

        int num = createSENumber++;

        InvocationEvent wrapMe = new InvocationEvent(new Object(), () -> {

            if (num != dispatchSENumber++) {

                System.err.println("num: " + num);

                System.err.println("dispatchSENumber: " + dispatchSENumber);

                throw new RuntimeException("Wrong order");

            }

        });

        try {

            /*

             * SequencedEvent is a package private class, which cannot be instantiated

             * by importing. So use reflection to create an instance.

             */

            Class<? extends AWTEvent> seqClass = (Class<? extends AWTEvent>) Class.forName("java.awt.SequencedEvent");

            Constructor<? extends AWTEvent>

                    seqConst = seqClass.getConstructor(AWTEvent.class);

            seqConst.setAccessible(true);

            return seqConst.newInstance(wrapMe);

        } catch (Throwable err) {

            throw new RuntimeException("Unable to instantiate SequencedEvent",err);

        }

    }

}