/*

 * Copyright (c) 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.oldobject;

import java.lang.reflect.Modifier;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

import jdk.jfr.Recording;

import jdk.jfr.consumer.RecordedEvent;

import jdk.jfr.consumer.RecordedObject;

import jdk.jfr.internal.test.WhiteBox;

import jdk.test.lib.Asserts;

import jdk.test.lib.jfr.EventNames;

import jdk.test.lib.jfr.Events;

/*

 * @test

 * @key jfr

 * @requires vm.gc == "null"

 * @library /test/lib /test/jdk

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

 * @run main/othervm -XX:TLABSize=2k -Xlog:gc+tlab=trace jdk.jfr.event.oldobject.TestFieldInformation

 */

public class TestFieldInformation {

    public static final Object[] testField = new Object[50];

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

        WhiteBox.setWriteAllObjectSamples(true);

        try (Recording recording = new Recording()) {

            recording.enable(EventNames.OldObjectSample).withoutStackTrace().with("cutoff", "infinity");

            recording.start();

            addToTestField();

            recording.stop();

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

            Events.hasEvents(events);

            for (RecordedEvent e : events) {

                if (hasValidField(e)) {

                    return;

                }

            }

            System.out.println(events);

            Asserts.fail("Could not find old object with field 'testField'");

        }

    }

    private static boolean hasValidField(RecordedEvent e) throws Exception {

        RecordedObject object = e.getValue("object");

        Set<Long> visited = new HashSet<>();

        while (object != null) {

            Long address = object.getValue("address");

            if (visited.contains(address)) {

                return false;

            }

            visited.add(address);

            RecordedObject referrer = object.getValue("referrer");

            RecordedObject fieldObject = referrer != null ? referrer.getValue("field") : null;

            if (fieldObject != null) {

                String name = fieldObject.getValue("name");

                if (name != null && name.equals("testField")) {

                    int modifiers = (short) fieldObject.getValue("modifiers");

                    if (!Modifier.isStatic(modifiers)) {

                        throw new Exception("Field should be static");

                    }

                    if (!Modifier.isPublic(modifiers)) {

                        throw new Exception("Field should be private");

                    }

                    if (!Modifier.isFinal(modifiers)) {

                        throw new Exception("Field should be final");

                    }

                    if (Modifier.isTransient(modifiers)) {

                        throw new Exception("Field should not be transient");

                    }

                    if (Modifier.isVolatile(modifiers)) {

                        throw new Exception("Field should not be volatile");

                    }

                    return true;

                }

            }

            object = referrer != null ? referrer.getValue("object") : null;

        }

        return false;

    }

    private static void addToTestField() {

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

            // Allocate array to trigger sampling code path for interpreter / c1

            testField[i] = new Object[1_000_000];

        }

    }

}