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.impl;
017    
018    import org.apache.commons.logging.Log;
019    import org.apache.commons.logging.LogFactory;
020    
021    import de.kumpe.hadooptimizer.EsWrappableMutator;
022    import de.kumpe.hadooptimizer.Mutator;
023    
024    /**
025     * The {@link IdentityMutator} effectively does nothing, it just passes the
026     * input-individual through.
027     * 
028     * @param <I>
029     *            the individuals' type
030     * 
031     * @author <a href="http://kumpe.de/christian/java">Christian Kumpe</a>
032     */
033    public final class IdentityMutator<I> implements Mutator<I>, EsWrappableMutator {
034            private static final long serialVersionUID = 1L;
035            private static final Log log = LogFactory.getLog(IdentityMutator.class);
036    
037            public IdentityMutator() {
038                    if (log.isDebugEnabled()) {
039                            log.debug("Constructing new IdentityMutator.");
040                    }
041            }
042    
043            @Override
044            public I mutate(final I individual) {
045                    return individual;
046            }
047    
048            @Override
049            public double[] mutate(final double[] individual, final double increment) {
050                    return individual;
051            }
052    
053            @Override
054            public double getMinIncrement() {
055                    return 0;
056            }
057    
058            @Override
059            public String toString() {
060                    return "IdentityMutator []";
061            }
062    }