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

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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,

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package jdk.jfr.api.consumer.filestream;

import java.nio.file.Files;

import java.nio.file.Path;

import java.time.Instant;

import java.util.ArrayList;

import java.util.List;

import java.util.concurrent.CyclicBarrier;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicReference;

import jdk.jfr.Event;

import jdk.jfr.Recording;

import jdk.jfr.consumer.EventStream;

/**

 * @test

 * @summary Test EventStream::setOrdered(...)

 * @key jfr

 * @requires vm.hasJFR

 * @library /test/lib

 * @run main/othervm jdk.jfr.api.consumer.filestream.TestOrdered

 */

public class TestOrdered {

    static class OrderedEvent extends Event {

    }

    static class Emitter extends Thread {

        private final CyclicBarrier barrier;

        public Emitter(CyclicBarrier barrier) {

            this.barrier = barrier;

        }

        @Override

        public void run() {

            OrderedEvent e1 = new OrderedEvent();

            e1.commit();

            try {

                barrier.await();

            } catch (Exception e) {

                e.printStackTrace();

                throw new Error("Unexpected exception in barrier");

            }

            OrderedEvent e2 = new OrderedEvent();

            e2.commit();

        }

    }

    private static final int THREAD_COUNT = 4;

    public static void main(String... args) throws Exception {

        Path p = makeUnorderedRecording();

        testSetOrderedTrue(p);

        testSetOrderedFalse(p);

    }

    private static void testSetOrderedTrue(Path p) throws Exception {

        AtomicReference<Instant> timestamp = new AtomicReference<>(Instant.MIN);

        try (EventStream es = EventStream.openFile(p)) {

            es.setOrdered(true);

            es.onEvent(e -> {

                Instant endTime = e.getEndTime();

                if (endTime.isBefore(timestamp.get())) {

                    throw new Error("Events are not ordered!");

                }

                timestamp.set(endTime);

            });

            es.start();

        }

    }

    private static void testSetOrderedFalse(Path p) throws Exception {

        AtomicReference<Instant> timestamp = new AtomicReference<>(Instant.MIN);

        AtomicBoolean unoreded = new AtomicBoolean(false);

        try (EventStream es = EventStream.openFile(p)) {

            es.setOrdered(false);

            es.onEvent(e -> {

                Instant endTime = e.getEndTime();

                if (endTime.isBefore(timestamp.get())) {

                    unoreded.set(true);

                    es.close();

                }

                timestamp.set(endTime);

            });

            es.start();

            if (!unoreded.get()) {

                throw new Exception("Expected at least some events to be out of order");

            }

        }

    }

    private static Path makeUnorderedRecording() throws Exception {

        CyclicBarrier barrier = new CyclicBarrier(THREAD_COUNT + 1);

        try (Recording r = new Recording()) {

            r.start();

            List<Emitter> emitters = new ArrayList<>();

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

                Emitter e = new Emitter(barrier);

                e.start();

                emitters.add(e);

            }

            // Thread buffers should now have one event each

            barrier.await();

            // Add another event to each thread buffer, so

            // events are bound to come out of order when they

            // are flushed

            for (Emitter e : emitters) {

                e.join();

            }

            r.stop();

            Path p = Files.createTempFile("recording", ".jfr");

            r.dump(p);

            return p;

        }

    }

}