/*

 * 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.

 *

 */

/*

 * @test

 * @bug     4858522

 * @summary Basic unit test of OperatingSystemMXBean.getProcessCpuTime()

 * @author  Steve Bohne

 */

/*

 * This test is just a sanity check and does not check for the correct

 * value.  The correct value should be checked manually:

 * Solaris/Linux:

 *   1. In a shell, enter the command: "ps -ef"

 *   2. The value (reported in seconds) is in the "TIME" column for the process

 * Windows NT/XP/2000:

 *   1. Hit Ctrl-Alt-Delete, select Task Manager, select Processes tab

 *   2. The value (reported in seconds) is in the "CPU Time" column for the

 *      process.  You may have to add this column via View menu-> Select

 *      Columns... item.

 * Windows 98/ME:

 *   Not supported.

 */

import com.sun.management.OperatingSystemMXBean;

import java.lang.management.*;

public class GetProcessCpuTime {

    private static OperatingSystemMXBean mbean =

        (com.sun.management.OperatingSystemMXBean)

        ManagementFactory.getOperatingSystemMXBean();

    // Careful with these values.

    private static final long MIN_TIME_FOR_PASS = 1;

    private static final long MAX_TIME_FOR_PASS = Long.MAX_VALUE;

    // No max time.

    private static boolean trace = false;

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

        if (args.length > 0 && args[0].equals("trace")) {

            trace = true;

        }

        // Consume cpu time

        double sum=0;

        for (int i=0; i <=2000000; i++) {

          sum += i;

          sum /= i;

        }

        long ns = mbean.getProcessCpuTime();

        if (ns == -1) {

            System.out.println("getProcessCpuTime() is not supported");

            return;

        }

        if (trace) {

            System.out.println("Process CPU time in ns: " + ns);

        }

        if (ns < MIN_TIME_FOR_PASS || ns > MAX_TIME_FOR_PASS) {

            throw new RuntimeException("Process CPU time " +

                                       "illegal value: " + ns + " ns " +

                                       "(MIN = " + MIN_TIME_FOR_PASS + "; " +

                                       "MAX = " + MAX_TIME_FOR_PASS + ")");

        }

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

    }

}