/*

 * Copyright (c) 2013, 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.  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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package jdk.jfr.event.runtime;

import java.time.Duration;

import java.util.List;

import java.util.concurrent.CountDownLatch;

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.TestThreadStartEndEvents

 */

/**

 * Starts and stops a number of threads in order.

 * Verifies that events are in the same order.

 */

public class TestThreadStartEndEvents {

    private final static String EVENT_NAME_THREAD_START = EventNames.ThreadStart;

    private final static String EVENT_NAME_THREAD_END = EventNames.ThreadEnd;

    private static final String THREAD_NAME_PREFIX = "TestThread-";

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

        // Test Java Thread Start event

        Recording recording = new Recording();

        recording.enable(EVENT_NAME_THREAD_START).withThreshold(Duration.ofMillis(0));

        recording.enable(EVENT_NAME_THREAD_END).withThreshold(Duration.ofMillis(0));

        recording.start();

        LatchedThread[] threads = startThreads();

        stopThreads(threads);

        recording.stop();

        int currThreadIndex = 0;

        long currentThreadId = Thread.currentThread().getId();

        List<RecordedEvent> events = Events.fromRecording(recording);

        Events.hasEvents(events);

        for (RecordedEvent event : events) {

            System.out.println("Event:" + event);

            if (event.getThread().getJavaThreadId() != currentThreadId) {

                continue;

            }

            // Threads should be started and stopped in the correct order.

            Events.assertEventThread(event, threads[currThreadIndex % threads.length]);

            String eventName = currThreadIndex < threads.length ? EVENT_NAME_THREAD_START : EVENT_NAME_THREAD_END;

            if (!eventName.equals(event.getEventType().getName())) {

                throw new Exception("Expected event of tyoe " + eventName + " but got " + event.getEventType().getName());

            }

            currThreadIndex++;

        }

    }

    private static LatchedThread[] startThreads() {

        LatchedThread threads[] = new LatchedThread[10];

        ThreadGroup threadGroup = new ThreadGroup("TestThreadGroup");

        for (int i = 0; i < threads.length; i++) {

            threads[i] = new LatchedThread(threadGroup, THREAD_NAME_PREFIX + i);

            threads[i].startThread();

            System.out.println("Started thread id=" + threads[i].getId());

        }

        return threads;

    }

    private static void stopThreads(LatchedThread[] threads) {

        for (LatchedThread thread : threads) {

            thread.stopThread();

            while (thread.isAlive()) {

                try {

                    Thread.sleep(5);

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }

            }

        }

    }

    private static class LatchedThread extends Thread {

        private final CountDownLatch start = new CountDownLatch(1);

        private final CountDownLatch stop = new CountDownLatch(1);

        public LatchedThread(ThreadGroup threadGroup, String name) {

            super(threadGroup, name);

        }

        public void run() {

            start.countDown();

            try {

                stop.await();

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

        public void startThread() {

            this.start();

            try {

                start.await();

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

        public void stopThread() {

            stop.countDown();

        }

    }

}