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diff --git a/src/main/java/org/apache/commons/math/genetics/OnePointCrossover.java b/src/main/java/org/apache/commons/math/genetics/OnePointCrossover.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.math.genetics;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+/**
+ * One point crossover policy. A random crossover point is selected and the
+ * first part from each parent is copied to the corresponding child, and the
+ * second parts are copied crosswise.
+ *
+ * Example:
+ * <pre>
+ * -C- denotes a crossover point
+ *                   -C-                                -C-
+ * p1 = (1 0 1 0 0 1  | 0 1 1)    X    p2 = (0 1 1 0 1 0  | 1 1 1)
+ *         \------------/ \-----/              \------------/ \-----/
+ *            ||         (*)                       ||        (**)
+ *            VV         (**)                      VV        (*)
+ *      /------------\ /-----\              /------------\ /-----\
+ * c1 = (1 0 1 0 0 1  | 1 1 1)    X    p2 = (0 1 1 0 1 0  | 0 1 1)
+ * </pre>
+ *
+ * This policy works only on {@link AbstractListChromosome}, and therefore it
+ * is parametrized by T. Moreover, the chromosomes must have same lengths.
+ *
+ * @param <T> generic type of the {@link AbstractListChromosome}s for crossover
+ * @since 2.0
+ * @version $Revision: 903046 $ $Date: 2010-01-26 03:07:26 +0100 (mar. 26 janv. 2010) $
+ *
+ */
+public class OnePointCrossover<T> implements CrossoverPolicy {
+
+    /**
+     * Performs one point crossover. A random crossover point is selected and the
+     * first part from each parent is copied to the corresponding child, and the
+     * second parts are copied crosswise.
+     *
+     * Example:
+     * -C- denotes a crossover point
+     *                   -C-                                -C-
+     * p1 = (1 0 1 0 0 1  | 0 1 1)    X    p2 = (0 1 1 0 1 0  | 1 1 1)
+     *         \------------/ \-----/              \------------/ \-----/
+     *            ||         (*)                       ||        (**)
+     *            VV         (**)                      VV        (*)
+     *      /------------\ /-----\              /------------\ /-----\
+     * c1 = (1 0 1 0 0 1  | 1 1 1)    X    p2 = (0 1 1 0 1 0  | 0 1 1)
+     *
+     * @param first first parent (p1)
+     * @param second second parent (p2)
+     * @return pair of two children (c1,c2)
+     */
+    @SuppressWarnings("unchecked") // OK because of instanceof checks
+    public ChromosomePair crossover(Chromosome first, Chromosome second) {
+        if (! (first instanceof AbstractListChromosome<?> && second instanceof AbstractListChromosome<?>)) {
+            throw new IllegalArgumentException("One point crossover works on FixedLengthChromosomes only.");
+        }
+        return crossover((AbstractListChromosome<T>) first, (AbstractListChromosome<T>) second);
+    }
+
+
+    /**
+     * Helper for {@link #crossover(Chromosome, Chromosome)}. Performs the actual crossover.
+     *
+     * @param first the first chromosome.
+     * @param second the second chromosome.
+     * @return the pair of new chromosomes that resulted from the crossover.
+     */
+    private ChromosomePair crossover(AbstractListChromosome<T> first, AbstractListChromosome<T> second) {
+        int length = first.getLength();
+        if (length != second.getLength())
+            throw new IllegalArgumentException("Both chromosomes must have same lengths.");
+
+        // array representations of the parents
+        List<T> parent1Rep = first.getRepresentation();
+        List<T> parent2Rep = second.getRepresentation();
+        // and of the children
+        ArrayList<T> child1Rep = new ArrayList<T> (first.getLength());
+        ArrayList<T> child2Rep = new ArrayList<T> (second.getLength());
+
+        // select a crossover point at random (0 and length makes no sense)
+        int crossoverIndex = 1 + (GeneticAlgorithm.getRandomGenerator().nextInt(length-2));
+
+        // copy the first part
+        for (int i = 0; i < crossoverIndex; i++) {
+            child1Rep.add(parent1Rep.get(i));
+            child2Rep.add(parent2Rep.get(i));
+        }
+        // and switch the second part
+        for (int i = crossoverIndex; i < length; i++) {
+            child1Rep.add(parent2Rep.get(i));
+            child2Rep.add(parent1Rep.get(i));
+        }
+
+        return new ChromosomePair(
+                first.newFixedLengthChromosome(child1Rep),
+                second.newFixedLengthChromosome(child2Rep)
+                );
+    }
+
+}