    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *      http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017    package org.apache.commons.math.random;
    018
    019    import java.util.Random;
    020
    021    /**
    022     * Extension of <code>java.util.Random</code> to implement
    023     * {@link RandomGenerator}.
    024     *
    025     * @since 1.1
    026     * @version $Revision: 811685 $ $Date: 2009-09-05 19:36:48 +0200 (sam. 05 sept. 2009) $
    027     */
    028    public class JDKRandomGenerator extends Random implements RandomGenerator {
    029
    030        /** Serializable version identifier. */
    031        private static final long serialVersionUID = -7745277476784028798L;
    032
    033        /** {@inheritDoc} */
    034        public void setSeed(int seed) {
    035            setSeed((long) seed);
    036        }
    037
    038        /** {@inheritDoc} */
    039        public void setSeed(int[] seed) {
    040            // the following number is the largest prime that fits in 32 bits (it is 2^32 - 5)
    041            final long prime = 4294967291l;
    042
    043            long combined = 0l;
    044            for (int s : seed) {
    045                combined = combined * prime + s;
    046            }
    047            setSeed(combined);
    048        }
    049
    050    }