001    /*
002     * Copyright 2011 Christian Kumpe http://kumpe.de/christian/java
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *     http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    package de.kumpe.hadooptimizer;
017    
018    import java.io.Serializable;
019    
020    import org.apache.commons.math.random.RandomGenerator;
021    
022    /**
023     * Implementing this interfaces enables injection of seeded
024     * {@link RandomGenerator} -instances.
025     * <p>
026     * In distributed environments it's important to have the random-generators
027     * seeded correctly (differently) to avoid correlations between the generated
028     * random numbers on different machines. The Framework injects correctly seeded
029     * {@link RandomGenerator} objects in all components of an
030     * {@link OptimizerConfiguration}.
031     * 
032     * @see OptimizerConfiguration#injectRandomGenerator(RandomGenerator)
033     * 
034     * @author <a href="http://kumpe.de/christian/java">Christian Kumpe</a>
035     */
036    public interface NeedsRandomGenerator extends Serializable {
037            /**
038             * Injects a {@link RandomGenerator} instance.
039             * 
040             * @param randomGenerator
041             *            the new {@link RandomGenerator} instance
042             */
043            void setRandomGenerator(RandomGenerator randomGenerator);
044    }