/*

 * Copyright (c) 2003, 2008, 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.

 *

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 */

/*

 * @test

 * @bug     4530538

 * @summary Basic Test for HotspotThreadMBean.getInternalThreadCount()

 *          and getInternalThreadCpuTime()

 * @author  Mandy Chung

 */

import sun.management.*;

import java.util.*;

import java.lang.management.ThreadMXBean;

import java.lang.management.ManagementFactory;

public class GetInternalThreads {

    private static HotspotThreadMBean mbean =

        ManagementFactoryHelper.getHotspotThreadMBean();

    // Minimum number of VM internal threads

    //   VM thread, watcher thread, Low memory detector, compiler thread

    private static final long MIN_VALUE_FOR_PASS = 4;

    private static final long MAX_VALUE_FOR_PASS = Long.MAX_VALUE;

    public static void main(String[] args) {

        long value = mbean.getInternalThreadCount();

        if (value < MIN_VALUE_FOR_PASS || value > MAX_VALUE_FOR_PASS) {

            throw new RuntimeException("Internal thread count " +

                                       "illegal value: " + value + " " +

                                       "(MIN = " + MIN_VALUE_FOR_PASS + "; " +

                                       "MAX = " + MAX_VALUE_FOR_PASS + ")");

        }

        System.out.println("Internal Thread Count = " + value);

        ThreadMXBean thread =

            ManagementFactory.getThreadMXBean();

        if (!thread.isThreadCpuTimeSupported()) {

            System.out.println("Thread Cpu Time is not supported.");

            return;

        }

        Map times = mbean.getInternalThreadCpuTimes();

        Iterator iter = times.entrySet().iterator();

        for (; iter.hasNext(); ) {

            Map.Entry entry = (Map.Entry) iter.next();

            System.out.println(entry.getKey() +

                " CPU time = " + entry.getValue() + "ns");

            if (((Long) entry.getValue()).longValue() < 0) {

                throw new RuntimeException("Thread CPU time" +

                    "illegal value: " + entry.getValue());

            }

        }

        System.out.println("Test passed.");

    }

}