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1   /**
2    * Copyright (c) 2004-2011 QOS.ch
3    * All rights reserved.
4    *
5    * Permission is hereby granted, free  of charge, to any person obtaining
6    * a  copy  of this  software  and  associated  documentation files  (the
7    * "Software"), to  deal in  the Software without  restriction, including
8    * without limitation  the rights to  use, copy, modify,  merge, publish,
9    * distribute,  sublicense, and/or sell  copies of  the Software,  and to
10   * permit persons to whom the Software  is furnished to do so, subject to
11   * the following conditions:
12   *
13   * The  above  copyright  notice  and  this permission  notice  shall  be
14   * included in all copies or substantial portions of the Software.
15   *
16   * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
17   * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
18   * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
19   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21   * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
22   * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23   *
24   */
25  package org.slf4j.helpers;
26  
27  class MyRandom {
28  
29      private final static long m = 200000000041L; // a prime number
30      private final static long a = 2000000011L; // a prime number
31  
32      long y;
33      long unused;
34      int bits = 32;
35  
36      public MyRandom() {
37          this(System.nanoTime());
38      }
39  
40      public MyRandom(long seed) {
41          this.y = seed;
42      }
43  
44      int nextInt() {
45          // we don't really care about the randomness of this
46          // generator
47          y = (a * y + 1) % m;
48          unused = y >>> (48 - bits); // just exercise the >>> operator
49          return (int) (y);
50      }
51  }