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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * under the terms of the GNU General Public License version 2 only, as
 * 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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package jdk.jfr.api.consumer.recordingstream;

import java.time.Instant;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicReference;

import jdk.jfr.Event;
import jdk.jfr.Recording;
import jdk.jfr.consumer.EventStream;
import jdk.jfr.consumer.RecordingStream;

/**
 * @test
 * @summary Tests RecordingStream::close()
 * @key jfr
 * @requires vm.hasJFR
 * @library /test/lib
 * @run main/othervm jdk.jfr.api.consumer.recordingstream.TestClose
 */
public class TestClose {

    private static class CloseEvent extends Event {
    }

    public static void main(String... args) throws Exception {
        testCloseUnstarted();
        testCloseStarted();
        testCloseTwice();
        testCloseStreaming();
        testCloseMySelf();
        testCloseNoEvents();
    }

    private static void testCloseMySelf() throws Exception {
        log("Entering testCloseMySelf()");
        CountDownLatch l1 = new CountDownLatch(1);
        CountDownLatch l2 = new CountDownLatch(1);
        RecordingStream r = new RecordingStream();
        r.onEvent(e -> {
            try {
                l1.await();
                r.close();
                l2.countDown();
            } catch (InterruptedException ie) {
                throw new Error(ie);
            }
        });
        r.startAsync();
        CloseEvent c = new CloseEvent();
        c.commit();
        l1.countDown();
        l2.await();
        log("Leaving testCloseMySelf()");
    }

    private static void testCloseStreaming() throws Exception {
        log("Entering testCloseStreaming()");
        CountDownLatch streaming = new CountDownLatch(1);
        RecordingStream r = new RecordingStream();
        AtomicLong count = new AtomicLong();
        r.onEvent(e -> {
            if (count.incrementAndGet() > 100) {
                streaming.countDown();
            }
        });
        r.startAsync();
        var streamingLoop = CompletableFuture.runAsync(() -> {
            while (true) {
                CloseEvent c = new CloseEvent();
                c.commit();
            }
        });
        streaming.await();
        r.close();
        streamingLoop.cancel(true);
        log("Leaving testCloseStreaming()");
    }

    private static void testCloseStarted() {
        log("Entering testCloseStarted()");
        RecordingStream r = new RecordingStream();
        r.startAsync();
        r.close();
        log("Leaving testCloseStarted()");
    }

    private static void testCloseUnstarted() {
        log("Entering testCloseUnstarted()");
        RecordingStream r = new RecordingStream();
        r.close();
        log("Leaving testCloseUnstarted()");
    }

    private static void testCloseTwice() {
        log("Entering testCloseTwice()");
        RecordingStream r = new RecordingStream();
        r.startAsync();
        r.close();
        r.close();
        log("Leaving testCloseTwice()");
    }

    private static void testCloseNoEvents() throws Exception {
        try (Recording r = new Recording()) {
            r.start();
            CountDownLatch finished = new CountDownLatch(2);
            AtomicReference<Thread> streamingThread = new AtomicReference<>();
            try (EventStream es = EventStream.openRepository()) {
                es.setStartTime(Instant.EPOCH);
                es.onFlush( () -> {
                    streamingThread.set(Thread.currentThread());
                    finished.countDown();;
                });
                es.startAsync();
                finished.await();
            } // <- EventStream::close should terminate thread
            while (streamingThread.get().isAlive()) {
                Thread.sleep(10);
            }
        }
    }

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