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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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 *

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package jdk.jfr.jvm;

import jdk.jfr.Event;

import jdk.jfr.internal.JVM;

import java.util.List;

/**

 * @test TestGetAllEventClasses

 * @key jfr

 * @requires vm.hasJFR

 * @library /test/lib /test/jdk

 * @modules jdk.jfr/jdk.jfr.internal

 *

 * @build jdk.jfr.jvm.HelloWorldEvent1

 * @build jdk.jfr.jvm.HelloWorldEvent2

 * @run main/othervm jdk.jfr.jvm.TestGetAllEventClasses

 */

public class TestGetAllEventClasses {

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

        JVM jvm = JVM.getJVM();

        // before creating  native

        assertEmptyEventList(jvm);

        jvm.createNativeJFR();

        // after creating native

        assertEmptyEventList(jvm);

        // Test event class load is triggered and only once

        Class<? extends Event> clazz = initialize("jdk.jfr.jvm.HelloWorldEvent1");

        // check that the event class is registered

        assertEventsIncluded(jvm, clazz);

        // second active use of the same event class should not add another class

        // to the list - it would already be loaded

        clazz = initialize(clazz);

        assertEventsIncluded(jvm, clazz);

        // second event class

        Class<? extends Event> clazz2 = initialize("jdk.jfr.jvm.HelloWorldEvent2");

        // the list of event classes should now have two classes registered

        assertEventsIncluded(jvm, clazz, clazz2);

        // verify that an abstract event class is not included

        Class<? extends Event> abstractClass = initialize(MyAbstractEvent.class); // to run <clinit>

        assertEventsExcluded(jvm, abstractClass);

        // verify that a class that is yet to run its <clinit> is not included in the list of event classes

        assertEventsExcluded(jvm, MyUnInitializedEvent.class);

        // ensure old classes are not lost

        assertEventsIncluded(jvm, clazz, clazz2);

        jvm.destroyNativeJFR();

    }

    private static Class<? extends Event> initialize(String name) throws ClassNotFoundException {

        // Class.forName() will force the class to run its <clinit> method

        return Class.forName(name).asSubclass(Event.class);

    }

    private static Class<? extends Event> initialize(Class<? extends Event> event) throws ClassNotFoundException {

        return initialize(event.getName());

    }

    private static void assertEmptyEventList(JVM jvm) {

        if (!jvm.getAllEventClasses().isEmpty()) {

            throw new AssertionError("should not have any event classes registered!");

        }

    }

    @SafeVarargs

    private static void assertEventsExcluded(JVM jvm, Class<? extends Event>... targetEvents) {

        assertEvents(jvm, false, targetEvents);

    }

    @SafeVarargs

    private static void assertEventsIncluded(JVM jvm, Class<? extends Event>... targetEvents) {

        assertEvents(jvm, true, targetEvents);

    }

    @SafeVarargs

    @SuppressWarnings("rawtypes")

    private static void assertEvents(JVM jvm, boolean inclusion, Class<? extends Event>... targetEvents) {

        final List list = jvm.getAllEventClasses();

        for (Class<? extends Event> ev : targetEvents) {

           if (list.contains(ev)) {

               if (inclusion) {

                   continue;

               }

               throw new AssertionError(ev.getName() + " in list but should not be!");

           }

           if (!inclusion) {

               continue;

           }

           throw new AssertionError(ev.getName() + " in not in list but should be!");

       }

    }

    private static abstract class MyAbstractEvent extends Event {}

    private static class MyUnInitializedEvent extends Event {}

}