/*

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 *

 * This code is free software; you can redistribute it and/or modify it

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 * 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     4858522

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

 * @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:

 *   1. In a shell, enter the command: "sar -r 1"

 *   2. The value (reported in pages) is in the "freemem" column.

 * Linux:

 *   1. In a shell, enter the command: "cat /proc/meminfo"

 *   2. The value (reported in bytes) is in "Mem" entry, "free" column.

 * Windows NT/XP/2000:

 *   1. Hit Ctrl-Alt-Delete, select Task Manager, go to Performance tab.

 *   2. The value (reported in Kbytes) is in the entry "Available" in the

 *      "Physical Memory" box.

 * Windows 98/ME:

 *   1. Run Start->Programs->Accessories->System Tools->System Information.

 *   2. Use the "XXXMB RAM" and "XX% system resources free" to determine free

 *      physical memory.

 */

import com.sun.management.OperatingSystemMXBean;

import java.lang.management.*;

public class GetFreePhysicalMemorySize {

    private static OperatingSystemMXBean mbean =

        (com.sun.management.OperatingSystemMXBean)

        ManagementFactory.getOperatingSystemMXBean();

    // Careful with these values.

    private static final long MIN_SIZE_FOR_PASS = 1;

    // Max size for pass dynamically determined below.

    private static long       max_size_for_pass = Long.MAX_VALUE;

    private static boolean trace = false;

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

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

            trace = true;

        }

        long max_size = mbean.getTotalPhysicalMemorySize();

        if (max_size > 0) {

            max_size_for_pass = max_size;

        }

        long size = mbean.getFreePhysicalMemorySize();

        if (trace) {

            System.out.println("Free physical memory size in bytes: " + size);

        }

        if (size < MIN_SIZE_FOR_PASS || size > max_size_for_pass) {

            throw new RuntimeException("Free physical memory size " +

                                       "illegal value: " + size + " bytes " +

                                       "(MIN = " + MIN_SIZE_FOR_PASS + "; " +

                                       "MAX = " + max_size_for_pass + ")");

        }

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

    }

}