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

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 * 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).

 *

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package jdk.jfr.api.consumer.streaming;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.concurrent.CountDownLatch;

import java.util.concurrent.TimeUnit;

import java.util.concurrent.atomic.AtomicBoolean;

import jdk.jfr.Event;

import jdk.jfr.FlightRecorder;

import jdk.jfr.Name;

import jdk.jfr.Recording;

import jdk.jfr.consumer.EventStream;

import jdk.jfr.consumer.RecordingStream;

/**

 * @test

 * @summary Verifies that EventStream::openRepository() read from the latest flush

 * @key jfr

 * @requires vm.hasJFR

 * @library /test/lib

 * @run main/othervm jdk.jfr.api.consumer.streaming.TestLatestEvent

 */

public class TestLatestEvent {

    @Name("NotLatest")

    static class NotLatestEvent extends Event {

        public int id;

    }

    @Name("Latest")

    static class LatestEvent extends Event {

    }

    @Name("MakeChunks")

    static class MakeChunks extends Event {

    }

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

        CountDownLatch notLatestEvent = new CountDownLatch(6);

        CountDownLatch beginChunks = new CountDownLatch(1);

        try (RecordingStream r = new RecordingStream()) {

            r.onEvent("MakeChunks", event-> {

                System.out.println(event);

                beginChunks.countDown();

            });

            r.onEvent("NotLatest", event -> {

                System.out.println(event);

                notLatestEvent.countDown();

            });

            r.startAsync();

            MakeChunks e = new MakeChunks();

            e.commit();

            System.out.println("Waiting for first chunk");

            beginChunks.await();

            // Create 5 chunks with events in the repository

            for (int i = 0; i < 5; i++) {

                System.out.println("Creating empty chunk");

                try (Recording r1 = new Recording()) {

                    r1.start();

                    NotLatestEvent notLatest = new NotLatestEvent();

                    notLatest.id = i;

                    notLatest.commit();

                    r1.stop();

                }

            }

            System.out.println("All empty chunks created");

            // Create event in new chunk

            NotLatestEvent notLatest = new NotLatestEvent();

            notLatest.id = 5;

            notLatest.commit();

            // This latch ensures thatNotLatest has been

            // flushed and a new valid position has been written

            // to the chunk header

            notLatestEvent.await(80, TimeUnit.SECONDS);

            if (notLatestEvent.getCount() != 0) {

               Recording rec =  FlightRecorder.getFlightRecorder().takeSnapshot();

               Path p = Paths.get("error-not-latest.jfr").toAbsolutePath();

               rec.dump(p);

               System.out.println("Dumping repository as a file for inspection at " + p);

               throw new Exception("Timeout 80 s. Expected 6 event, but got "  + notLatestEvent.getCount());

            }

            try (EventStream s = EventStream.openRepository()) {

                System.out.println("EventStream opened");

                AtomicBoolean foundLatest = new AtomicBoolean();

                s.onEvent(event -> {

                    String name = event.getEventType().getName();

                    System.out.println("Found event " + name);

                    foundLatest.set(name.equals("Latest"));

                });

                s.startAsync();

                // Must loop here as there is no guarantee

                // that the parser thread starts before event

                // is flushed

                while (!foundLatest.get()) {

                    LatestEvent latest = new LatestEvent();

                    latest.commit();

                    System.out.println("Latest event emitted. Waiting 1 s ...");

                    Thread.sleep(1000);

                }

            }

        }

    }

}