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 * 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.  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.event.runtime;

import static jdk.test.lib.Asserts.assertTrue;

import java.time.Duration;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import jdk.jfr.Recording;
import jdk.jfr.consumer.RecordedEvent;
import jdk.test.lib.jfr.EventNames;
import jdk.test.lib.jfr.Events;

/**
 * @test
 * @key jfr
 * @requires vm.hasJFR
 * @library /test/lib
 * @run main/othervm jdk.jfr.event.runtime.TestJavaThreadStatisticsEvent
 */
public class TestJavaThreadStatisticsEvent {
    private static final String EVENT_NAME = EventNames.JavaThreadStatistics;

    private static final int THREAD_COUNT = 10;
    private static final Random RAND = new Random(4711);

    // verify thread count: 0 <= daemon <= active <= peak <= accumulated.
    public static void main(String[] args) throws Throwable {
        Recording recording = new Recording();
        recording.enable(EVENT_NAME).withThreshold(Duration.ofMillis(10));
        recording.start();

        List<Thread> threads = new ArrayList<>();
        for (int i = 0; i < THREAD_COUNT; i++) {
            Thread thread = new Thread(TestJavaThreadStatisticsEvent::sleepRandom);
            thread.start();
            threads.add(thread);
        }
        for (Thread thread : threads) {
            thread.join();
        }

        recording.stop();
        List<RecordedEvent> events = Events.fromRecording(recording);
        boolean isAnyFound = false;
        for (RecordedEvent event : events) {
            System.out.println("Event:" + event);
            isAnyFound = true;
            // verify thread count: 0 <= daemon <= active <= peak <= accumulated.
            long daemonCount = Events.assertField(event, "daemonCount").atLeast(0L).getValue();
            long activeCount = Events.assertField(event, "activeCount").atLeast(daemonCount).getValue();
            long peakCount = Events.assertField(event, "peakCount").atLeast(activeCount).atLeast(1L).getValue();
            Events.assertField(event, "accumulatedCount").atLeast(peakCount).getValue();
        }
        assertTrue(isAnyFound, "Correct event not found");
    }

    static void sleepRandom() {
        try {
            Thread.sleep(RAND.nextInt(10));
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}