/*

 * Copyright (c) 2016, 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.management.jfr.internal;

import java.util.Collections;

import java.util.List;

import java.util.Map;

import java.util.Set;

import java.util.concurrent.Callable;

import jdk.jfr.internal.management.ManagementSupport;

import jdk.management.jfr.FlightRecorderMXBean;

import jdk.management.jfr.SettingDescriptorInfo;

import sun.management.spi.PlatformMBeanProvider;

public final class FlightRecorderMXBeanProvider extends PlatformMBeanProvider {

    private final static class SingleMBeanComponent

            implements PlatformComponent<FlightRecorderMXBean> {

        private final String objectName;

        private final Class<FlightRecorderMXBean> mbeanInterface;

        public SingleMBeanComponent(String objectName,

                                    Class<FlightRecorderMXBean> mbeanInterface) {

            this.objectName = objectName;

            this.mbeanInterface = mbeanInterface;

        }

        @Override

        public Set<String> mbeanInterfaceNames() {

            return Collections.singleton(mbeanInterface.getName());

        }

        @Override

        public Map<String, FlightRecorderMXBean> nameToMBeanMap() {

            FlightRecorderMXBean bean = getFlightRecorderMXBean();

            if (bean != null) {

                return Collections.singletonMap(objectName, bean);

            } else {

                return Collections.emptyMap();

            }

        }

        @Override

        public String getObjectNamePattern() {

            return objectName;

        }

        @Override

        public Set<Class<? extends FlightRecorderMXBean>> mbeanInterfaces() {

            return Collections.singleton(mbeanInterface);

        }

    }

    private static Callable<FlightRecorderMXBean> flightRecorderMXBeanFactory;

    private static volatile FlightRecorderMXBean flightRecorderMXBean;

    private static FlightRecorderMXBean getFlightRecorderMXBean() {

        FlightRecorderMXBean bean = flightRecorderMXBean;

        if (bean == null) {

            SettingDescriptorInfo.from(null); // Sets flightRecorderMXBeanFactory under <clinit> lock

            synchronized (flightRecorderMXBeanFactory) {

                bean = flightRecorderMXBean;

                if (bean != null) {

                    return bean;

                }

                try {

                    bean = flightRecorderMXBean = flightRecorderMXBeanFactory.call();

                } catch (Exception e) {

                    ManagementSupport.logError("Could not create Flight Recorder "

                            + "instance for MBeanServer. " + e.getMessage());

                }

            }

        }

        return bean;

    }

    public static void setFlightRecorderMXBeanFactory(Callable<FlightRecorderMXBean> factory) {

        flightRecorderMXBeanFactory = factory;

    }

    @Override

    public List<PlatformComponent<?>> getPlatformComponentList() {

        String objectName = FlightRecorderMXBean.MXBEAN_NAME;

        Class<FlightRecorderMXBean> mbeanInterface = FlightRecorderMXBean.class;

        return Collections.singletonList(new SingleMBeanComponent(objectName, mbeanInterface));

    }

}