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diff --git a/src/main/java/org/apache/commons/math3/genetics/AbstractListChromosome.java b/src/main/java/org/apache/commons/math3/genetics/AbstractListChromosome.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.math3.genetics;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Chromosome represented by an immutable list of a fixed length.
+ *
+ * @param <T> type of the representation list
+ * @since 2.0
+ */
+public abstract class AbstractListChromosome<T> extends Chromosome {
+
+    /** List representing the chromosome */
+    private final List<T> representation;
+
+    /**
+     * Constructor, copying the input representation.
+     *
+     * @param representation inner representation of the chromosome
+     * @throws InvalidRepresentationException iff the <code>representation</code> can not represent
+     *     a valid chromosome
+     */
+    public AbstractListChromosome(final List<T> representation)
+            throws InvalidRepresentationException {
+        this(representation, true);
+    }
+
+    /**
+     * Constructor, copying the input representation.
+     *
+     * @param representation inner representation of the chromosome
+     * @throws InvalidRepresentationException iff the <code>representation</code> can not represent
+     *     a valid chromosome
+     */
+    public AbstractListChromosome(final T[] representation) throws InvalidRepresentationException {
+        this(Arrays.asList(representation));
+    }
+
+    /**
+     * Constructor.
+     *
+     * @param representation inner representation of the chromosome
+     * @param copyList if {@code true}, the representation will be copied, otherwise it will be
+     *     referenced.
+     * @since 3.3
+     */
+    public AbstractListChromosome(final List<T> representation, final boolean copyList) {
+        checkValidity(representation);
+        this.representation =
+                Collections.unmodifiableList(
+                        copyList ? new ArrayList<T>(representation) : representation);
+    }
+
+    /**
+     * Asserts that <code>representation</code> can represent a valid chromosome.
+     *
+     * @param chromosomeRepresentation representation of the chromosome
+     * @throws InvalidRepresentationException iff the <code>representation</code> can not represent
+     *     a valid chromosome
+     */
+    protected abstract void checkValidity(List<T> chromosomeRepresentation)
+            throws InvalidRepresentationException;
+
+    /**
+     * Returns the (immutable) inner representation of the chromosome.
+     *
+     * @return the representation of the chromosome
+     */
+    protected List<T> getRepresentation() {
+        return representation;
+    }
+
+    /**
+     * Returns the length of the chromosome.
+     *
+     * @return the length of the chromosome
+     */
+    public int getLength() {
+        return getRepresentation().size();
+    }
+
+    /**
+     * Creates a new instance of the same class as <code>this</code> is, with a given <code>
+     * arrayRepresentation</code>. This is needed in crossover and mutation operators, where we need
+     * a new instance of the same class, but with different array representation.
+     *
+     * <p>Usually, this method just calls a constructor of the class.
+     *
+     * @param chromosomeRepresentation the inner array representation of the new chromosome.
+     * @return new instance extended from FixedLengthChromosome with the given arrayRepresentation
+     */
+    public abstract AbstractListChromosome<T> newFixedLengthChromosome(
+            final List<T> chromosomeRepresentation);
+
+    /** {@inheritDoc} */
+    @Override
+    public String toString() {
+        return String.format("(f=%s %s)", getFitness(), getRepresentation());
+    }
+}