1 /*
   2  * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug     4858522
  27  * @summary Basic unit test of OperatingSystemMXBean.getFreeSwapSpaceSize()
  28  * @author  Steve Bohne
  29  * @modules jdk.management
  30  */
  31 
  32 /*
  33  * This test is just a sanity check and does not check for the correct
  34  * value.  The correct value should be checked manually:
  35  * Solaris:
  36  *   1. In a shell, enter the command: "swap -l"
  37  *   2. The value (reported in blocks) is in the "free" column.
  38  * Linux:
  39  *   1. In a shell, enter the command: "cat /proc/meminfo"
  40  *   2. The value (reported in bytes) is in "Swap" entry, "free" column.
  41  * Windows NT/XP/2000:
  42  *   Unknown.
  43  * Windows 98/ME:
  44  *   Unknown.
  45  */
  46 
  47 import com.sun.management.OperatingSystemMXBean;
  48 import java.lang.management.*;
  49 
  50 public class GetFreeSwapSpaceSize {
  51 
  52     private static OperatingSystemMXBean mbean =
  53         (com.sun.management.OperatingSystemMXBean)
  54         ManagementFactory.getOperatingSystemMXBean();
  55 
  56     // Careful with these values.
  57     // Min size is zero since the system can run of swap spaces
  58     private static final long MIN_SIZE_FOR_PASS = 0;
  59     // Max size for pass dynamically determined below.
  60     private static long       max_size_for_pass = Long.MAX_VALUE;
  61 
  62     private static boolean trace = false;
  63 
  64     public static void main(String args[]) throws Exception {
  65         if (args.length > 0 && args[0].equals("trace")) {
  66             trace = true;
  67         }
  68 
  69         long max_size = mbean.getTotalSwapSpaceSize();
  70         if (max_size > 0) {
  71             max_size_for_pass = max_size;
  72         }
  73 
  74         long size = mbean.getFreeSwapSpaceSize();
  75 
  76         if (trace) {
  77             System.out.println("Free swap space size in bytes: " + size);
  78         }
  79 
  80         if (size < MIN_SIZE_FOR_PASS || size > max_size_for_pass) {
  81             throw new RuntimeException("Free swap space size " +
  82                                        "illegal value: " + size + " bytes " +
  83                                        "(MIN = " + MIN_SIZE_FOR_PASS + "; " +
  84                                        "MAX = " + max_size_for_pass + ")");
  85         }
  86 
  87         System.out.println("Test passed.");
  88     }
  89 }