/*

 * Copyright (c) 2017, 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.

 *

 * 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

 * or visit www.oracle.com if you need additional information or have any

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 */

package org.graalvm.compiler.hotspot.jmx;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import java.util.Map;

import java.util.Set;

import jdk.vm.ci.runtime.JVMCI;

import jdk.vm.ci.runtime.JVMCICompiler;

import jdk.vm.ci.runtime.JVMCIRuntime;

import org.graalvm.compiler.hotspot.HotSpotGraalCompiler;

import sun.management.spi.PlatformMBeanProvider;

import sun.management.spi.PlatformMBeanProvider.PlatformComponent;

public final class GraalMBeans extends PlatformMBeanProvider {

    @Override

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

        List<PlatformComponent<?>> components = new ArrayList<>();

        try {

            Object bean = findGraalRuntimeBean();

            if (bean != null) {

                components.add(new HotSpotRuntimeMBeanComponent(bean));

            }

        } catch (InternalError | LinkageError err) {

            // go on and ignore

        }

        return components;

    }

    public static Object findGraalRuntimeBean() {

        JVMCIRuntime r = JVMCI.getRuntime();

        JVMCICompiler c = r.getCompiler();

        if (c instanceof HotSpotGraalCompiler) {

            return ((HotSpotGraalCompiler) c).mbean();

        }

        return null;

    }

    private static final class HotSpotRuntimeMBeanComponent implements PlatformComponent<Object> {

        private final String name;

        private final Object mbean;

        HotSpotRuntimeMBeanComponent(Object mbean) {

            this.name = "org.graalvm.compiler.hotspot:type=Options";

            this.mbean = mbean;

        }

        @Override

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

            return Collections.emptySet();

        }

        @Override

        public Set<String> mbeanInterfaceNames() {

            return Collections.emptySet();

        }

        @Override

        public String getObjectNamePattern() {

            return name;

        }

        @Override

        public Map<String, Object> nameToMBeanMap() {

            return Collections.<String, Object>singletonMap(name, mbean);

        }

    }

}