View Javadoc

1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.math.random;
18  
19  import java.util.Random;
20  
21  /**
22   * Extension of <code>java.util.Random</code> to implement 
23   * {@link RandomGenerator}.
24   *
25   * @since 1.1
26   * @version $Revision: 796543 $ $Date: 2009-07-21 17:32:38 -0400 (Tue, 21 Jul 2009) $
27   */
28  public class JDKRandomGenerator extends Random implements RandomGenerator {
29  
30      /** Serializable version identifier. */
31      private static final long serialVersionUID = -7745277476784028798L;
32  
33      /** {@inheritDoc} */
34      public void setSeed(int seed) {
35          setSeed((long) seed);
36      }
37  
38      /** {@inheritDoc} */
39      public void setSeed(int[] seed) {
40          // the following number is the largest prime that fits in 32 bits (it is 2^32 - 5)
41          final long prime = 4294967291l;
42  
43          long combined = 0l;
44          for (int s : seed) {
45              combined = combined * prime + s;
46          }
47          setSeed(combined);
48      }
49  
50  }