ceph/src/rocksdb/java/src/test/java/org/rocksdb/PlatformRandomHelper.java

   1 // Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 // This source code is licensed under the BSD-style license found in the
   3 // LICENSE file in the root directory of this source tree. An additional grant
   4 // of patent rights can be found in the PATENTS file in the same directory.
   5
   6 package org.rocksdb;
   7
   8 import java.util.Random;
   9
  10 /**
  11  * Helper class to get the appropriate Random class instance dependent
  12  * on the current platform architecture (32bit vs 64bit)
  13  */
  14 public class PlatformRandomHelper {
  15     /**
  16      * Determine if OS is 32-Bit/64-Bit
  17      *
  18      * @return boolean value indicating if operating system is 64 Bit.
  19      */
  20     public static boolean isOs64Bit(){
  21       final boolean is64Bit;
  22       if (System.getProperty("os.name").contains("Windows")) {
  23         is64Bit = (System.getenv("ProgramFiles(x86)") != null);
  24       } else {
  25         is64Bit = (System.getProperty("os.arch").contains("64"));
  26       }
  27       return is64Bit;
  28     }
  29
  30     /**
  31      * Factory to get a platform specific Random instance
  32      *
  33      * @return {@link java.util.Random} instance.
  34      */
  35     public static Random getPlatformSpecificRandomFactory(){
  36       if (isOs64Bit()) {
  37         return new Random();
  38       }
  39       return new Random32Bit();
  40     }
  41
  42     /**
  43      * Random32Bit is a class which overrides {@code nextLong} to
  44      * provide random numbers which fit in size_t. This workaround
  45      * is necessary because there is no unsigned_int &lt; Java 8
  46      */
  47     private static class Random32Bit extends Random {
  48       @Override
  49       public long nextLong(){
  50       return this.nextInt(Integer.MAX_VALUE);
  51     }
  52     }
  53
  54     /**
  55      * Utility class constructor
  56      */
  57     private PlatformRandomHelper() { }
  58 }