/*
 * Copyright 2002-2005 The Apache Software Foundation.
 * 
 * Licensed 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.lang;

import java.lang.reflect.Array;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;

/**
 * <p>Operations on arrays, primitive arrays (like <code>int[]</code>) and
 * primitive wrapper arrays (like <code>Integer[]</code>).</p>
 * 
 * <p>This class tries to handle <code>null</code> input gracefully.
 * An exception will not be thrown for a <code>null</code>
 * array input. However, an Object array that contains a <code>null</code>
 * element may throw an exception. Each method documents its behaviour.</p>
 *
 * @author Stephen Colebourne
 * @author Moritz Petersen
 * @author <a href="mailto:fredrik@westermarck.com">Fredrik Westermarck</a>
 * @author Nikolay Metchev
 * @author Matthew Hawthorne
 * @author Tim O'Brien
 * @author Pete Gieser
 * @author Gary Gregory
 * @author <a href="mailto:equinus100@hotmail.com">Ashwin S</a>
 * @author Maarten Coene
 * @since 2.0
 * @version $Id: ArrayUtils.java,v 1.1.1.1 2007/07/23 16:01:53 chm Exp $
 */
public class ArrayUtils {

    /**
     * An empty immutable <code>Object</code> array.
     */
    public static final Object[] EMPTY_OBJECT_ARRAY = new Object[0];
    /**
     * An empty immutable <code>Class</code> array.
     */
    public static final Class[] EMPTY_CLASS_ARRAY = new Class[0];
    /**
     * An empty immutable <code>String</code> array.
     */
    public static final String[] EMPTY_STRING_ARRAY = new String[0];
    /**
     * An empty immutable <code>long</code> array.
     */
    public static final long[] EMPTY_LONG_ARRAY = new long[0];
    /**
     * An empty immutable <code>Long</code> array.
     */
    public static final Long[] EMPTY_LONG_OBJECT_ARRAY = new Long[0];
    /**
     * An empty immutable <code>int</code> array.
     */
    public static final int[] EMPTY_INT_ARRAY = new int[0];
    /**
     * An empty immutable <code>Integer</code> array.
     */
    public static final Integer[] EMPTY_INTEGER_OBJECT_ARRAY = new Integer[0];
    /**
     * An empty immutable <code>short</code> array.
     */
    public static final short[] EMPTY_SHORT_ARRAY = new short[0];
    /**
     * An empty immutable <code>Short</code> array.
     */
    public static final Short[] EMPTY_SHORT_OBJECT_ARRAY = new Short[0];
    /**
     * An empty immutable <code>byte</code> array.
     */
    public static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
    /**
     * An empty immutable <code>Byte</code> array.
     */
    public static final Byte[] EMPTY_BYTE_OBJECT_ARRAY = new Byte[0];
    /**
     * An empty immutable <code>double</code> array.
     */
    public static final double[] EMPTY_DOUBLE_ARRAY = new double[0];
    /**
     * An empty immutable <code>Double</code> array.
     */
    public static final Double[] EMPTY_DOUBLE_OBJECT_ARRAY = new Double[0];
    /**
     * An empty immutable <code>float</code> array.
     */
    public static final float[] EMPTY_FLOAT_ARRAY = new float[0];
    /**
     * An empty immutable <code>Float</code> array.
     */
    public static final Float[] EMPTY_FLOAT_OBJECT_ARRAY = new Float[0];
    /**
     * An empty immutable <code>boolean</code> array.
     */
    public static final boolean[] EMPTY_BOOLEAN_ARRAY = new boolean[0];
    /**
     * An empty immutable <code>Boolean</code> array.
     */
    public static final Boolean[] EMPTY_BOOLEAN_OBJECT_ARRAY = new Boolean[0];
    /**
     * An empty immutable <code>char</code> array.
     */
    public static final char[] EMPTY_CHAR_ARRAY = new char[0];
    /**
     * An empty immutable <code>Character</code> array.
     */
    public static final Character[] EMPTY_CHARACTER_OBJECT_ARRAY = new Character[0];

    /**
     * <p>ArrayUtils instances should NOT be constructed in standard programming.
     * Instead, the class should be used as <code>ArrayUtils.clone(new int[] {2})</code>.</p>
     *
     * <p>This constructor is public to permit tools that require a JavaBean instance
     * to operate.</p>
     */
    public ArrayUtils() {
    }
    
    // Basic methods handling multi-dimensional arrays
    //-----------------------------------------------------------------------
    /**
     * <p>Outputs an array as a String, treating <code>null</code> as an empty array.</p>
     *
     * <p>Multi-dimensional arrays are handled correctly, including
     * multi-dimensional primitive arrays.</p>
     *
     * <p>The format is that of Java source code, for example <code>{a,b}</code>.</p>
     * 
     * @param array  the array to get a toString for, may be <code>null</code>
     * @return a String representation of the array, '{}' if null array input
     */
    public static String toString(Object array) {
        return toString(array, "{}");
    }

    /**
     * <p>Outputs an array as a String handling <code>null</code>s.</p>
     *
     * <p>Multi-dimensional arrays are handled correctly, including
     * multi-dimensional primitive arrays.</p>
     *
     * <p>The format is that of Java source code, for example <code>{a,b}</code>.</p>
     * 
     * @param array  the array to get a toString for, may be <code>null</code>
     * @param stringIfNull  the String to return if the array is <code>null</code>
     * @return a String representation of the array
     */    
    public static String toString(Object array, String stringIfNull) {
        if (array == null) {
            return stringIfNull;
        }
        return new ToStringBuilder(array, ToStringStyle.SIMPLE_STYLE).append(array).toString();
    }

    /**
     * <p>Get a hashCode for an array handling multi-dimensional arrays correctly.</p>
     * 
     * <p>Multi-dimensional primitive arrays are also handled correctly by this method.</p>
     * 
     * @param array  the array to get a hashCode for, may be <code>null</code>
     * @return a hashCode for the array, zero if null array input
     */
    public static int hashCode(Object array) {
        return new HashCodeBuilder().append(array).toHashCode();
    }

    /**
     * <p>Compares two arrays, using equals(), handling multi-dimensional arrays
     * correctly.</p>
     * 
     * <p>Multi-dimensional primitive arrays are also handled correctly by this method.</p>
     * 
     * @param array1  the left hand array to compare, may be <code>null</code>
     * @param array2  the right hand array to compare, may be <code>null</code>
     * @return <code>true</code> if the arrays are equal
     */
    public static boolean isEquals(Object array1, Object array2) {
        return new EqualsBuilder().append(array1, array2).isEquals();
    }

    // To map
    //-----------------------------------------------------------------------
    /**
     * <p>Converts the given array into a {@link java.util.Map}. Each element of the array
     * must be either a {@link java.util.Map.Entry} or an Array, containing at least two
     * elements, where the first element is used as key and the second as
     * value.</p>
     *
     * <p>This method can be used to initialize:</p>
     * <pre>
     * // Create a Map mapping colors.
     * Map colorMap = MapUtils.toMap(new String[][] {{
     *     {"RED", "#FF0000"},
     *     {"GREEN", "#00FF00"},
     *     {"BLUE", "#0000FF"}});
     * </pre>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     *
     * @param array  an array whose elements are either a {@link java.util.Map.Entry} or
     *  an Array containing at least two elements, may be <code>null</code>
     * @return a <code>Map</code> that was created from the array
     * @throws IllegalArgumentException  if one element of this Array is
     *  itself an Array containing less then two elements
     * @throws IllegalArgumentException  if the array contains elements other
     *  than {@link java.util.Map.Entry} and an Array
     */
    public static Map toMap(Object[] array) {
        if (array == null) {
            return null;
        }
        final Map map = new HashMap((int) (array.length * 1.5));
        for (int i = 0; i < array.length; i++) {
            Object object = array[i];
            if (object instanceof Map.Entry) {
                Map.Entry entry = (Map.Entry) object;
                map.put(entry.getKey(), entry.getValue());
            } else if (object instanceof Object[]) {
                Object[] entry = (Object[]) object;
                if (entry.length < 2) {
                    throw new IllegalArgumentException("Array element " + i + ", '"
                        + object
                        + "', has a length less than 2");
                }
                map.put(entry[0], entry[1]);
            } else {
                throw new IllegalArgumentException("Array element " + i + ", '"
                        + object
                        + "', is neither of type Map.Entry nor an Array");
            }
        }
        return map;
    }

    // Clone
    //-----------------------------------------------------------------------
    /**
     * <p>Shallow clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>The objects in the array are not cloned, thus there is no special
     * handling for multi-dimensional arrays.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to shallow clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static Object[] clone(Object[] array) {
        if (array == null) {
            return null;
        }
        return (Object[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static long[] clone(long[] array) {
        if (array == null) {
            return null;
        }
        return (long[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static int[] clone(int[] array) {
        if (array == null) {
            return null;
        }
        return (int[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static short[] clone(short[] array) {
        if (array == null) {
            return null;
        }
        return (short[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static char[] clone(char[] array) {
        if (array == null) {
            return null;
        }
        return (char[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static byte[] clone(byte[] array) {
        if (array == null) {
            return null;
        }
        return (byte[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static double[] clone(double[] array) {
        if (array == null) {
            return null;
        }
        return (double[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static float[] clone(float[] array) {
        if (array == null) {
            return null;
        }
        return (float[]) array.clone();
    }

    /**
     * <p>Clones an array returning a typecast result and handling
     * <code>null</code>.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to clone, may be <code>null</code>
     * @return the cloned array, <code>null</code> if <code>null</code> input
     */
    public static boolean[] clone(boolean[] array) {
        if (array == null) {
            return null;
        }
        return (boolean[]) array.clone();
    }

    // Subarrays
    //-----------------------------------------------------------------------
    /**
     * <p>Produces a new array containing the elements between
     * the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * <p>The component type of the subarray is always the same as
     * that of the input array. Thus, if the input is an array of type
     * <code>Date</code>, the following usage is envisaged:</p>
     *
     * <pre>
     * Date[] someDates = (Date[])ArrayUtils.subarray(allDates, 2, 5);
     * </pre>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static Object[] subarray(Object[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        Class type = array.getClass().getComponentType();
        if (newSize <= 0) {
            return (Object[]) Array.newInstance(type, 0);
        }
        Object[] subarray = (Object[]) Array.newInstance(type, newSize);
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>long</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static long[] subarray(long[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_LONG_ARRAY;
        }

        long[] subarray = new long[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>int</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static int[] subarray(int[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_INT_ARRAY;
        }

        int[] subarray = new int[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>short</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static short[] subarray(short[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_SHORT_ARRAY;
        }

        short[] subarray = new short[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>char</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static char[] subarray(char[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_CHAR_ARRAY;
        }

        char[] subarray = new char[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>byte</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static byte[] subarray(byte[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_BYTE_ARRAY;
        }

        byte[] subarray = new byte[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>double</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static double[] subarray(double[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_DOUBLE_ARRAY;
        }

        double[] subarray = new double[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>float</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static float[] subarray(float[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_FLOAT_ARRAY;
        }

        float[] subarray = new float[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    /**
     * <p>Produces a new <code>boolean</code> array containing the elements
     * between the start and end indices.</p>
     *
     * <p>The start index is inclusive, the end index exclusive.
     * Null array input produces null output.</p>
     *
     * @param array  the array
     * @param startIndexInclusive  the starting index. Undervalue (&lt;0)
     *      is promoted to 0, overvalue (&gt;array.length) results
     *      in an empty array.
     * @param endIndexExclusive  elements up to endIndex-1 are present in the
     *      returned subarray. Undervalue (&lt; startIndex) produces
     *      empty array, overvalue (&gt;array.length) is demoted to
     *      array length.
     * @return a new array containing the elements between
     *      the start and end indices.
     * @since 2.1
     */
    public static boolean[] subarray(boolean[] array, int startIndexInclusive, int endIndexExclusive) {
        if (array == null) {
            return null;
        }
        if (startIndexInclusive < 0) {
            startIndexInclusive = 0;
        }
        if (endIndexExclusive > array.length) {
            endIndexExclusive = array.length;
        }
        int newSize = endIndexExclusive - startIndexInclusive;
        if (newSize <= 0) {
            return EMPTY_BOOLEAN_ARRAY;
        }

        boolean[] subarray = new boolean[newSize];
        System.arraycopy(array, startIndexInclusive, subarray, 0, newSize);
        return subarray;
    }

    // Is same length
    //-----------------------------------------------------------------------
    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.
     *
     * <p>Any multi-dimensional aspects of the arrays are ignored.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */    
    public static boolean isSameLength(Object[] array1, Object[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(long[] array1, long[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(int[] array1, int[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(short[] array1, short[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(char[] array1, char[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(byte[] array1, byte[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(double[] array1, double[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(float[] array1, float[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    /**
     * <p>Checks whether two arrays are the same length, treating
     * <code>null</code> arrays as length <code>0</code>.</p>
     * 
     * @param array1 the first array, may be <code>null</code>
     * @param array2 the second array, may be <code>null</code>
     * @return <code>true</code> if length of arrays matches, treating
     *  <code>null</code> as an empty array
     */
    public static boolean isSameLength(boolean[] array1, boolean[] array2) {
        if ((array1 == null && array2 != null && array2.length > 0) ||
            (array2 == null && array1 != null && array1.length > 0) ||
            (array1 != null && array2 != null && array1.length != array2.length)) {
                return false;
        }
        return true;
    }

    //-----------------------------------------------------------------------
    /**
     * <p>Returns the length of the specified array.
     * This method can deal with <code>Object</code> arrays and with primitive arrays.</p>
     *
     * <p>If the input array is <code>null</code>, <code>0</code> is returned.</p>
     *
     * <pre>
     * ArrayUtils.getLength(null)            = 0
     * ArrayUtils.getLength([])              = 0
     * ArrayUtils.getLength([null])          = 1
     * ArrayUtils.getLength([true, false])   = 2
     * ArrayUtils.getLength([1, 2, 3])       = 3
     * ArrayUtils.getLength(["a", "b", "c"]) = 3
     * </pre>
     *
     * @param array  the array to retrieve the length from, may be null
     * @return The length of the array, or <code>0</code> if the array is <code>null</code>
     * @throws IllegalArgumentException if the object arguement is not an array.
     * @since 2.1
     */
    public static int getLength(Object array) {
        if (array == null) {
            return 0;
        } else {
            return Array.getLength(array);
        }
    }

    /**
     * <p>Checks whether two arrays are the same type taking into account
     * multi-dimensional arrays.</p>
     * 
     * @param array1 the first array, must not be <code>null</code>
     * @param array2 the second array, must not be <code>null</code>
     * @return <code>true</code> if type of arrays matches
     * @throws IllegalArgumentException if either array is <code>null</code>
     */    
    public static boolean isSameType(Object array1, Object array2) {
        if (array1 == null || array2 == null) {
            throw new IllegalArgumentException("The Array must not be null");
        }
        return array1.getClass().getName().equals(array2.getClass().getName());
    }

    // Reverse
    //-----------------------------------------------------------------------
    /** 
     * <p>Reverses the order of the given array.</p>
     *
     * <p>There is no special handling for multi-dimensional arrays.</p>
     *
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(Object[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        Object tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(long[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        long tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(int[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        int tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(short[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        short tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(char[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        char tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(byte[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        byte tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(double[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        double tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(float[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        float tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    /**
     * <p>Reverses the order of the given array.</p>
     * 
     * <p>This method does nothing if <code>null</code> array input.</p>
     * 
     * @param array  the array to reverse, may be <code>null</code>
     */
    public static void reverse(boolean[] array) {
        if (array == null) {
            return;
        }
        int i = 0;
        int j = array.length - 1;
        boolean tmp;
        while (j > i) {
            tmp = array[j];
            array[j] = array[i];
            array[i] = tmp;
            j--;
            i++;
        }
    }

    // IndexOf search
    // ----------------------------------------------------------------------
    
    // Object IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given object in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param objectToFind  the object to find, may be <code>null</code>
     * @return the index of the object within the array, 
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(Object[] array, Object objectToFind) {
        return indexOf(array, objectToFind, 0);
    }

    /**
     * <p>Find the index of the given object in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return <code>-1</code>.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param objectToFind  the object to find, may be <code>null</code>
     * @param startIndex  the index to start searching at
     * @return the index of the object within the array starting at the index,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(Object[] array, Object objectToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        if (objectToFind == null) {
            for (int i = startIndex; i < array.length; i++) {
                if (array[i] == null) {
                    return i;
                }
            }
        } else {
            for (int i = startIndex; i < array.length; i++) {
                if (objectToFind.equals(array[i])) {
                    return i;
                }
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given object within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param objectToFind  the object to find, may be <code>null</code>
     * @return the last index of the object within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(Object[] array, Object objectToFind) {
        return lastIndexOf(array, objectToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given object in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return <code>-1</code>. A startIndex larger than
     * the array length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param objectToFind  the object to find, may be <code>null</code>
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the object within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(Object[] array, Object objectToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        if (objectToFind == null) {
            for (int i = startIndex; i >= 0; i--) {
                if (array[i] == null) {
                    return i;
                }
            }
        } else {
            for (int i = startIndex; i >= 0; i--) {
                if (objectToFind.equals(array[i])) {
                    return i;
                }
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the object is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param objectToFind  the object to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(Object[] array, Object objectToFind) {
        return indexOf(array, objectToFind) != -1;
    }

    // long IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(long[] array, long valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(long[] array, long valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(long[] array, long valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(long[] array, long valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(long[] array, long valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // int IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(int[] array, int valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(int[] array, int valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(int[] array, int valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(int[] array, int valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(int[] array, int valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // short IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(short[] array, short valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(short[] array, short valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(short[] array, short valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(short[] array, short valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(short[] array, short valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // char IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     * @since 2.1
     */
    public static int indexOf(char[] array, char valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     * @since 2.1
     */
    public static int indexOf(char[] array, char valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     * @since 2.1
     */
    public static int lastIndexOf(char[] array, char valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     * @since 2.1
     */
    public static int lastIndexOf(char[] array, char valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     * @since 2.1
     */
    public static boolean contains(char[] array, char valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // byte IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(byte[] array, byte valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(byte[] array, byte valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(byte[] array, byte valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(byte[] array, byte valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(byte[] array, byte valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // double IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(double[] array, double valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value within a given tolerance in the array.
     * This method will return the index of the first value which falls between the region
     * defined by valueToFind - tolerance and valueToFind + tolerance.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param tolerance tolerance of the search
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(double[] array, double valueToFind, double tolerance) {
        return indexOf(array, valueToFind, 0, tolerance);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(double[] array, double valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.
     * This method will return the index of the first value which falls between the region
     * defined by valueToFind - tolerance and valueToFind + tolerance.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @param tolerance tolerance of the search
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(double[] array, double valueToFind, int startIndex, double tolerance) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        double min = valueToFind - tolerance;
        double max = valueToFind + tolerance;
        for (int i = startIndex; i < array.length; i++) {
            if (array[i] >= min && array[i] <= max) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(double[] array, double valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value within a given tolerance in the array.
     * This method will return the index of the last value which falls between the region
     * defined by valueToFind - tolerance and valueToFind + tolerance.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param tolerance tolerance of the search
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(double[] array, double valueToFind, double tolerance) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE, tolerance);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(double[] array, double valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.
     * This method will return the index of the last value which falls between the region
     * defined by valueToFind - tolerance and valueToFind + tolerance.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @param tolerance  search for value within plus/minus this amount
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(double[] array, double valueToFind, int startIndex, double tolerance) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        double min = valueToFind - tolerance;
        double max = valueToFind + tolerance;
        for (int i = startIndex; i >= 0; i--) {
            if (array[i] >= min && array[i] <= max) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(double[] array, double valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    /**
     * <p>Checks if a value falling within the given tolerance is in the
     * given array.  If the array contains a value within the inclusive range 
     * defined by (value - tolerance) to (value + tolerance).</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array
     * is passed in.</p>
     *
     * @param array  the array to search
     * @param valueToFind  the value to find
     * @param tolerance  the array contains the tolerance of the search
     * @return true if value falling within tolerance is in array
     */
    public static boolean contains(double[] array, double valueToFind, double tolerance) {
        return indexOf(array, valueToFind, 0, tolerance) != -1;
    }

    // float IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(float[] array, float valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(float[] array, float valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(float[] array, float valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(float[] array, float valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(float[] array, float valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // boolean IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(boolean[] array, boolean valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(boolean[] array, boolean valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(boolean[] array, boolean valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(boolean[] array, boolean valueToFind, int startIndex) {
        if (ArrayUtils.isEmpty(array)) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(boolean[] array, boolean valueToFind) {
        return indexOf(array, valueToFind) != -1;
    }

    // Primitive/Object array converters
    // ----------------------------------------------------------------------
    
    // Long array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Longs to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Long</code> array, may be <code>null</code>
     * @return a <code>long</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static long[] toPrimitive(Long[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_LONG_ARRAY;
        }
        final long[] result = new long[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].longValue();
        }
        return result;
    }
    
    /**
     * <p>Converts an array of object Long to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Long</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>long</code> array, <code>null</code> if null array input
     */
    public static long[] toPrimitive(Long[] array, long valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_LONG_ARRAY;
        }
        final long[] result = new long[array.length];
        for (int i = 0; i < array.length; i++) {
            Long b = array[i];
            result[i] = (b == null ? valueForNull : b.longValue());
        }
        return result;
    }
    
    /**
     * <p>Converts an array of primitive longs to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>long</code> array
     * @return a <code>Long</code> array, <code>null</code> if null array input
     */
    public static Long[] toObject(long[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_LONG_OBJECT_ARRAY;
        }
        final Long[] result = new Long[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Long(array[i]);
        }
        return result;
    }

    // Int array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Integers to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Integer</code> array, may be <code>null</code>
     * @return an <code>int</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static int[] toPrimitive(Integer[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_INT_ARRAY;
        }
        final int[] result = new int[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].intValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Integer to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Integer</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return an <code>int</code> array, <code>null</code> if null array input
     */
    public static int[] toPrimitive(Integer[] array, int valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_INT_ARRAY;
        }
        final int[] result = new int[array.length];
        for (int i = 0; i < array.length; i++) {
            Integer b = array[i];
            result[i] = (b == null ? valueForNull : b.intValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive ints to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  an <code>int</code> array
     * @return an <code>Integer</code> array, <code>null</code> if null array input
     */
    public static Integer[] toObject(int[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_INTEGER_OBJECT_ARRAY;
        }
        final Integer[] result = new Integer[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Integer(array[i]);
        }
        return result;
    }
    
    // Short array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Shorts to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Short</code> array, may be <code>null</code>
     * @return a <code>byte</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static short[] toPrimitive(Short[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_SHORT_ARRAY;
        }
        final short[] result = new short[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].shortValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Short to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Short</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>byte</code> array, <code>null</code> if null array input
     */
    public static short[] toPrimitive(Short[] array, short valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_SHORT_ARRAY;
        }
        final short[] result = new short[array.length];
        for (int i = 0; i < array.length; i++) {
            Short b = array[i];
            result[i] = (b == null ? valueForNull : b.shortValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive shorts to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>short</code> array
     * @return a <code>Short</code> array, <code>null</code> if null array input
     */
    public static Short[] toObject(short[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_SHORT_OBJECT_ARRAY;
        }
        final Short[] result = new Short[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Short(array[i]);
        }
        return result;
    }    

    // Byte array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Bytes to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Byte</code> array, may be <code>null</code>
     * @return a <code>byte</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static byte[] toPrimitive(Byte[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BYTE_ARRAY;
        }
        final byte[] result = new byte[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].byteValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Bytes to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Byte</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>byte</code> array, <code>null</code> if null array input
     */
    public static byte[] toPrimitive(Byte[] array, byte valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BYTE_ARRAY;
        }
        final byte[] result = new byte[array.length];
        for (int i = 0; i < array.length; i++) {
            Byte b = array[i];
            result[i] = (b == null ? valueForNull : b.byteValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive bytes to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>byte</code> array
     * @return a <code>Byte</code> array, <code>null</code> if null array input
     */
    public static Byte[] toObject(byte[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BYTE_OBJECT_ARRAY;
        }
        final Byte[] result = new Byte[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Byte(array[i]);
        }
        return result;
    }  
    
    // Double array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Doubles to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Double</code> array, may be <code>null</code>
     * @return a <code>double</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static double[] toPrimitive(Double[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_DOUBLE_ARRAY;
        }
        final double[] result = new double[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].doubleValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Doubles to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Double</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>double</code> array, <code>null</code> if null array input
     */
    public static double[] toPrimitive(Double[] array, double valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_DOUBLE_ARRAY;
        }
        final double[] result = new double[array.length];
        for (int i = 0; i < array.length; i++) {
            Double b = array[i];
            result[i] = (b == null ? valueForNull : b.doubleValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive doubles to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>double</code> array
     * @return a <code>Double</code> array, <code>null</code> if null array input
     */
    public static Double[] toObject(double[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_DOUBLE_OBJECT_ARRAY;
        }
        final Double[] result = new Double[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Double(array[i]);
        }
        return result;
    }

    //   Float array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Floats to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Float</code> array, may be <code>null</code>
     * @return a <code>float</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static float[] toPrimitive(Float[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_FLOAT_ARRAY;
        }
        final float[] result = new float[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].floatValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Floats to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Float</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>float</code> array, <code>null</code> if null array input
     */
    public static float[] toPrimitive(Float[] array, float valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_FLOAT_ARRAY;
        }
        final float[] result = new float[array.length];
        for (int i = 0; i < array.length; i++) {
            Float b = array[i];
            result[i] = (b == null ? valueForNull : b.floatValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive floats to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>float</code> array
     * @return a <code>Float</code> array, <code>null</code> if null array input
     */
    public static Float[] toObject(float[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_FLOAT_OBJECT_ARRAY;
        }
        final Float[] result = new Float[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = new Float(array[i]);
        }
        return result;
    }

    // Boolean array converters
    // ----------------------------------------------------------------------
    /**
     * <p>Converts an array of object Booleans to primitives.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Boolean</code> array, may be <code>null</code>
     * @return a <code>boolean</code> array, <code>null</code> if null array input
     * @throws NullPointerException if array content is <code>null</code>
     */
    public static boolean[] toPrimitive(Boolean[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BOOLEAN_ARRAY;
        }
        final boolean[] result = new boolean[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = array[i].booleanValue();
        }
        return result;
    }

    /**
     * <p>Converts an array of object Booleans to primitives handling <code>null</code>.</p>
     * 
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>Boolean</code> array, may be <code>null</code>
     * @param valueForNull  the value to insert if <code>null</code> found
     * @return a <code>boolean</code> array, <code>null</code> if null array input
     */
    public static boolean[] toPrimitive(Boolean[] array, boolean valueForNull) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BOOLEAN_ARRAY;
        }
        final boolean[] result = new boolean[array.length];
        for (int i = 0; i < array.length; i++) {
            Boolean b = array[i];
            result[i] = (b == null ? valueForNull : b.booleanValue());
        }
        return result;
    }

    /**
     * <p>Converts an array of primitive booleans to objects.</p>
     *
     * <p>This method returns <code>null</code> if <code>null</code> array input.</p>
     * 
     * @param array  a <code>boolean</code> array
     * @return a <code>Boolean</code> array, <code>null</code> if null array input
     */
    public static Boolean[] toObject(boolean[] array) {
        if (array == null) {
            return null;
        } else if (array.length == 0) {
            return EMPTY_BOOLEAN_OBJECT_ARRAY;
        }
        final Boolean[] result = new Boolean[array.length];
        for (int i = 0; i < array.length; i++) {
            result[i] = (array[i] ? Boolean.TRUE : Boolean.FALSE);
        }
        return result;
    }

    // ----------------------------------------------------------------------
    /**
     * <p>Checks if an array of Objects is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(Object[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive longs is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(long[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive ints is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(int[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive shorts is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(short[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive chars is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(char[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive bytes is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(byte[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive doubles is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(double[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive floats is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(float[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Checks if an array of primitive booleans is empty or <code>null</code>.</p>
     *
     * @param array  the array to test
     * @return <code>true</code> if the array is empty or <code>null</code>
     * @since 2.1
     */
    public static boolean isEmpty(boolean[] array) {
        if (array == null || array.length == 0) {
            return true;
        }
        return false;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(null, null)     = null
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * ArrayUtils.addAll([null], [null]) = [null, null]
     * ArrayUtils.addAll(["a", "b", "c"], ["1", "2", "3"]) = ["a", "b", "c", "1", "2", "3"]
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array, may be <code>null</code>
     * @param array2  the second array whose elements are added to the new array, may be <code>null</code>
     * @return The new array, <code>null</code> if <code>null</code> array inputs. 
     *      The type of the new array is the type of the first array.
     * @since 2.1
     */
    public static Object[] addAll(Object[] array1, Object[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        Object[] joinedArray = (Object[]) Array.newInstance(array1.getClass().getComponentType(),
                                                            array1.length + array2.length);
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new boolean[] array.
     * @since 2.1
     */
    public static boolean[] addAll(boolean[] array1, boolean[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        boolean[] joinedArray = new boolean[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new char[] array.
     * @since 2.1
     */
    public static char[] addAll(char[] array1, char[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        char[] joinedArray = new char[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new byte[] array.
     * @since 2.1
     */
    public static byte[] addAll(byte[] array1, byte[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        byte[] joinedArray = new byte[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new short[] array.
     * @since 2.1
     */
    public static short[] addAll(short[] array1, short[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        short[] joinedArray = new short[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new int[] array.
     * @since 2.1
     */
    public static int[] addAll(int[] array1, int[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        int[] joinedArray = new int[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new long[] array.
     * @since 2.1
     */
    public static long[] addAll(long[] array1, long[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        long[] joinedArray = new long[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new float[] array.
     * @since 2.1
     */
    public static float[] addAll(float[] array1, float[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        float[] joinedArray = new float[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Adds all the elements of the given arrays into a new array.</p>
     * <p>The new array contains all of the element of <code>array1</code> followed
     * by all of the elements <code>array2</code>. When an array is returned, it is always
     * a new array.</p>
     *
     * <pre>
     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
     * ArrayUtils.addAll([], [])         = []
     * </pre>
     *
     * @param array1  the first array whose elements are added to the new array.
     * @param array2  the second array whose elements are added to the new array.
     * @return The new double[] array.
     * @since 2.1
     */
    public static double[] addAll(double[] array1, double[] array2) {
        if (array1 == null) {
            return clone(array2);
        } else if (array2 == null) {
            return clone(array1);
        }
        double[] joinedArray = new double[array1.length + array2.length];
        System.arraycopy(array1, 0, joinedArray, 0, array1.length);
        System.arraycopy(array2, 0, joinedArray, array1.length, array2.length);
        return joinedArray;
    }

    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, null)      = [null]
     * ArrayUtils.add(null, "a")       = ["a"]
     * ArrayUtils.add(["a"], null)     = ["a", null]
     * ArrayUtils.add(["a"], "b")      = ["a", "b"]
     * ArrayUtils.add(["a", "b"], "c") = ["a", "b", "c"]
     * </pre>
     * 
     * @param array  the array to "add" the element to, may be <code>null</code>
     * @param element  the object to add
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static Object[] add(Object[] array, Object element) {
        Class type = (array != null ? array.getClass() : (element != null ? element.getClass() : Object.class));
        Object[] newArray = (Object[]) copyArrayGrow1(array, type);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, true)          = [true]
     * ArrayUtils.add([true], false)       = [true, false]
     * ArrayUtils.add([true, false], true) = [true, false, true]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static boolean[] add(boolean[] array, boolean element) {
        boolean[] newArray = (boolean[])copyArrayGrow1(array, Boolean.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static byte[] add(byte[] array, byte element) {
        byte[] newArray = (byte[])copyArrayGrow1(array, Byte.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, '0')       = ['0']
     * ArrayUtils.add(['1'], '0')      = ['1', '0']
     * ArrayUtils.add(['1', '0'], '1') = ['1', '0', '1']
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static char[] add(char[] array, char element) {
        char[] newArray = (char[])copyArrayGrow1(array, Character.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static double[] add(double[] array, double element) {
        double[] newArray = (double[])copyArrayGrow1(array, Double.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static float[] add(float[] array, float element) {
        float[] newArray = (float[])copyArrayGrow1(array, Float.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static int[] add(int[] array, int element) {
        int[] newArray = (int[])copyArrayGrow1(array, Integer.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static long[] add(long[] array, long element) {
        long[] newArray = (long[])copyArrayGrow1(array, Long.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * <p>Copies the given array and adds the given element at the end of the new array.</p>
     *
     * <p>The new array contains the same elements of the input
     * array plus the given element in the last position. The component type of 
     * the new array is the same as that of the input array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0)   = [0]
     * ArrayUtils.add([1], 0)    = [1, 0]
     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
     * </pre>
     * 
     * @param array  the array to copy and add the element to, may be <code>null</code>
     * @param element  the object to add at the last index of the new array
     * @return A new array containing the existing elements plus the new element
     * @since 2.1
     */
    public static short[] add(short[] array, short element) {
        short[] newArray = (short[])copyArrayGrow1(array, Short.TYPE);
        newArray[newArray.length - 1] = element;
        return newArray;
    }
    
    /**
     * Returns a copy of the given array of size 1 greater than the argument. 
     * The last value of the array is left to the default value.
     * 
     * @param array The array to copy, must not be <code>null</code>.
     * @param newArrayComponentType If <code>array</code> is <code>null</code>, create a 
     * size 1 array of this type.
     * @return A new copy of the array of size 1 greater than the input.
     */    
    private static Object copyArrayGrow1(Object array, Class newArrayComponentType) {
        if (array != null) {
            int arrayLength = Array.getLength(array);
            Object newArray = Array.newInstance(array.getClass().getComponentType(), arrayLength + 1);
            System.arraycopy(array, 0, newArray, 0, arrayLength);
            return newArray;
        } else {
            return Array.newInstance(newArrayComponentType, 1);
        }
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0, null)      = [null]
     * ArrayUtils.add(null, 0, "a")       = ["a"]
     * ArrayUtils.add(["a"], 1, null)     = ["a", null]
     * ArrayUtils.add(["a"], 1, "b")      = ["a", "b"]
     * ArrayUtils.add(["a", "b"], 3, "c") = ["a", "b", "c"]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static Object[] add(Object[] array, int index, Object element) {
        Class clss = null;
        if(array != null) {
            clss = array.getClass().getComponentType();
        } else
        if(element != null) {
            clss = element.getClass();
        } else {
            return new Object[] { null };
        }
        return (Object[]) add( array, index, element, clss );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0, true)          = [true]
     * ArrayUtils.add([true], 0, false)       = [false, true]
     * ArrayUtils.add([false], 1, true)       = [false, true]
     * ArrayUtils.add([true, false], 1, true) = [true, true, false]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static boolean[] add(boolean[] array, int index, boolean element) {
        return (boolean[]) add( array, index, new Boolean(element), Boolean.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add(null, 0, 'a')            = ['a']
     * ArrayUtils.add(['a'], 0, 'b')           = ['b', 'a']
     * ArrayUtils.add(['a', 'b'], 0, 'c')      = ['c', 'a', 'b']
     * ArrayUtils.add(['a', 'b'], 1, 'k')      = ['a', 'k', 'b']
     * ArrayUtils.add(['a', 'b', 'c'], 1, 't') = ['a', 't', 'b', 'c']
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static char[] add(char[] array, int index, char element) {
        return (char[]) add( array, index, new Character(element), Character.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1], 0, 2)         = [2, 1]
     * ArrayUtils.add([2, 6], 2, 3)      = [2, 6, 3]
     * ArrayUtils.add([2, 6], 0, 1)      = [1, 2, 6]
     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static byte[] add(byte[] array, int index, byte element) {
        return (byte[]) add( array, index, new Byte(element), Byte.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1], 0, 2)         = [2, 1]
     * ArrayUtils.add([2, 6], 2, 10)     = [2, 6, 10]
     * ArrayUtils.add([2, 6], 0, -4)     = [-4, 2, 6]
     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static short[] add(short[] array, int index, short element) {
        return (short[]) add( array, index, new Short(element), Short.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1], 0, 2)         = [2, 1]
     * ArrayUtils.add([2, 6], 2, 10)     = [2, 6, 10]
     * ArrayUtils.add([2, 6], 0, -4)     = [-4, 2, 6]
     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static int[] add(int[] array, int index, int element) {
        return (int[]) add( array, index, new Integer(element), Integer.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1L], 0, 2L)           = [2L, 1L]
     * ArrayUtils.add([2L, 6L], 2, 10L)      = [2L, 6L, 10L]
     * ArrayUtils.add([2L, 6L], 0, -4L)      = [-4L, 2L, 6L]
     * ArrayUtils.add([2L, 6L, 3L], 2, 1L)   = [2L, 6L, 1L, 3L]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static long[] add(long[] array, int index, long element) {
        return (long[]) add( array, index, new Long(element), Long.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1.1f], 0, 2.2f)               = [2.2f, 1.1f]
     * ArrayUtils.add([2.3f, 6.4f], 2, 10.5f)        = [2.3f, 6.4f, 10.5f]
     * ArrayUtils.add([2.6f, 6.7f], 0, -4.8f)        = [-4.8f, 2.6f, 6.7f]
     * ArrayUtils.add([2.9f, 6.0f, 0.3f], 2, 1.0f)   = [2.9f, 6.0f, 1.0f, 0.3f]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static float[] add(float[] array, int index, float element) {
        return (float[]) add( array, index, new Float(element), Float.TYPE );
    }
    
    /**
     * <p>Inserts the specified element at the specified position in the array. 
     * Shifts the element currently at that position (if any) and any subsequent
     * elements to the right (adds one to their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array plus the given element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, a new one element array is returned
     *  whose component type is the same as the element.</p>
     * 
     * <pre>
     * ArrayUtils.add([1.1], 0, 2.2)              = [2.2, 1.1]
     * ArrayUtils.add([2.3, 6.4], 2, 10.5)        = [2.3, 6.4, 10.5]
     * ArrayUtils.add([2.6, 6.7], 0, -4.8)        = [-4.8, 2.6, 6.7]
     * ArrayUtils.add([2.9, 6.0, 0.3], 2, 1.0)    = [2.9, 6.0, 1.0, 0.3]
     * </pre>
     * 
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @return A new array containing the existing elements and the new element
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index > array.length).
     */
    public static double[] add(double[] array, int index, double element) {
        return (double[]) add( array, index, new Double(element), Double.TYPE );
    }
    
    /**
     * Underlying implementation of add(array, index, element) methods. 
     * The last parameter is the class, which may not equal element.getClass 
     * for primitives.
     *
     * @param array  the array to add the element to, may be <code>null</code>
     * @param index  the position of the new object
     * @param element  the object to add
     * @param clss the type of the element being added
     * @return A new array containing the existing elements and the new element
     */
    private static Object add(Object array, int index, Object element, Class clss) {
        if (array == null) {
            if (index != 0) {
                throw new IndexOutOfBoundsException("Index: " + index + ", Length: 0");
            }
            Object joinedArray = Array.newInstance(clss, 1);
            Array.set(joinedArray, 0, element);
            return joinedArray;
        }
        int length = Array.getLength(array);
        if (index > length || index < 0) {
            throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + length);
        }
        Object result = Array.newInstance(clss, length + 1);
        System.arraycopy(array, 0, result, 0, index);
        Array.set(result, index, element);
        if (index < length) {
            System.arraycopy(array, index, result, index + 1, length - index);
        }
        return result;
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove(["a"], 0)           = []
     * ArrayUtils.remove(["a", "b"], 0)      = ["b"]
     * ArrayUtils.remove(["a", "b"], 1)      = ["a"]
     * ArrayUtils.remove(["a", "b", "c"], 1) = ["a", "c"]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static Object[] remove(Object[] array, int index) {
        return (Object[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, "a")            = null
     * ArrayUtils.removeElement([], "a")              = []
     * ArrayUtils.removeElement(["a"], "b")           = ["a"]
     * ArrayUtils.removeElement(["a", "b"], "a")      = ["b"]
     * ArrayUtils.removeElement(["a", "b", "a"], "a") = ["b", "a"]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static Object[] removeElement(Object[] array, Object element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([true], 0)              = []
     * ArrayUtils.remove([true, false], 0)       = [false]
     * ArrayUtils.remove([true, false], 1)       = [true]
     * ArrayUtils.remove([true, true, false], 1) = [true, false]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static boolean[] remove(boolean[] array, int index) {
        return (boolean[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, true)                = null
     * ArrayUtils.removeElement([], true)                  = []
     * ArrayUtils.removeElement([true], false)             = [true]
     * ArrayUtils.removeElement([true, false], false)      = [true]
     * ArrayUtils.removeElement([true, false, true], true) = [false, true]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static boolean[] removeElement(boolean[] array, boolean element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1], 0)          = []
     * ArrayUtils.remove([1, 0], 0)       = [0]
     * ArrayUtils.remove([1, 0], 1)       = [1]
     * ArrayUtils.remove([1, 0, 1], 1)    = [1, 1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static byte[] remove(byte[] array, int index) {
        return (byte[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1)        = null
     * ArrayUtils.removeElement([], 1)          = []
     * ArrayUtils.removeElement([1], 0)         = [1]
     * ArrayUtils.removeElement([1, 0], 0)      = [1]
     * ArrayUtils.removeElement([1, 0, 1], 1)   = [0, 1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static byte[] removeElement(byte[] array, byte element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove(['a'], 0)           = []
     * ArrayUtils.remove(['a', 'b'], 0)      = ['b']
     * ArrayUtils.remove(['a', 'b'], 1)      = ['a']
     * ArrayUtils.remove(['a', 'b', 'c'], 1) = ['a', 'c']
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static char[] remove(char[] array, int index) {
        return (char[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 'a')            = null
     * ArrayUtils.removeElement([], 'a')              = []
     * ArrayUtils.removeElement(['a'], 'b')           = ['a']
     * ArrayUtils.removeElement(['a', 'b'], 'a')      = ['b']
     * ArrayUtils.removeElement(['a', 'b', 'a'], 'a') = ['b', 'a']
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static char[] removeElement(char[] array, char element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1.1], 0)           = []
     * ArrayUtils.remove([2.5, 6.0], 0)      = [6.0]
     * ArrayUtils.remove([2.5, 6.0], 1)      = [2.5]
     * ArrayUtils.remove([2.5, 6.0, 3.8], 1) = [2.5, 3.8]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static double[] remove(double[] array, int index) {
        return (double[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1.1)            = null
     * ArrayUtils.removeElement([], 1.1)              = []
     * ArrayUtils.removeElement([1.1], 1.2)           = [1.1]
     * ArrayUtils.removeElement([1.1, 2.3], 1.1)      = [2.3]
     * ArrayUtils.removeElement([1.1, 2.3, 1.1], 1.1) = [2.3, 1.1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static double[] removeElement(double[] array, double element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1.1], 0)           = []
     * ArrayUtils.remove([2.5, 6.0], 0)      = [6.0]
     * ArrayUtils.remove([2.5, 6.0], 1)      = [2.5]
     * ArrayUtils.remove([2.5, 6.0, 3.8], 1) = [2.5, 3.8]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static float[] remove(float[] array, int index) {
        return (float[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1.1)            = null
     * ArrayUtils.removeElement([], 1.1)              = []
     * ArrayUtils.removeElement([1.1], 1.2)           = [1.1]
     * ArrayUtils.removeElement([1.1, 2.3], 1.1)      = [2.3]
     * ArrayUtils.removeElement([1.1, 2.3, 1.1], 1.1) = [2.3, 1.1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static float[] removeElement(float[] array, float element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1], 0)         = []
     * ArrayUtils.remove([2, 6], 0)      = [6]
     * ArrayUtils.remove([2, 6], 1)      = [2]
     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static int[] remove(int[] array, int index) {
        return (int[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1)      = null
     * ArrayUtils.removeElement([], 1)        = []
     * ArrayUtils.removeElement([1], 2)       = [1]
     * ArrayUtils.removeElement([1, 3], 1)    = [3]
     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static int[] removeElement(int[] array, int element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1], 0)         = []
     * ArrayUtils.remove([2, 6], 0)      = [6]
     * ArrayUtils.remove([2, 6], 1)      = [2]
     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static long[] remove(long[] array, int index) {
        return (long[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1)      = null
     * ArrayUtils.removeElement([], 1)        = []
     * ArrayUtils.removeElement([1], 2)       = [1]
     * ArrayUtils.removeElement([1, 3], 1)    = [3]
     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static long[] removeElement(long[] array, long element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     *
     * <pre>
     * ArrayUtils.remove([1], 0)         = []
     * ArrayUtils.remove([2, 6], 0)      = [6]
     * ArrayUtils.remove([2, 6], 1)      = [2]
     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
     * </pre>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    public static short[] remove(short[] array, int index) {
        return (short[]) remove((Object) array, index);
    }
    
    /**
     * <p>Removes the first occurrence of the specified element from the
     * specified array. All subsequent elements are shifted to the left 
     * (substracts one from their indices). If the array doesn't contains
     * such an element, no elements are removed from the array.</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the first occurrence of the specified element. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <pre>
     * ArrayUtils.removeElement(null, 1)      = null
     * ArrayUtils.removeElement([], 1)        = []
     * ArrayUtils.removeElement([1], 2)       = [1]
     * ArrayUtils.removeElement([1, 3], 1)    = [3]
     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
     * </pre>
     * 
     * @param array  the array to remove the element from, may be <code>null</code>
     * @param element  the element to be removed
     * @return A new array containing the existing elements except the first
     *         occurrence of the specified element.
     * @since 2.1
     */
    public static short[] removeElement(short[] array, short element) {
        int index = indexOf(array, element);
        if (index == -1) {
            return clone(array);
        } 
        return remove(array, index);
    }
    
    /**
     * <p>Removes the element at the specified position from the specified array.
     * All subsequent elements are shifted to the left (substracts one from
     * their indices).</p>
     *
     * <p>This method returns a new array with the same elements of the input
     * array except the element on the specified position. The component 
     * type of the returned array is always the same as that of the input 
     * array.</p>
     *
     * <p>If the input array is <code>null</code>, an IndexOutOfBoundsException
     * will be thrown, because in that case no valid index can be specified.</p>
     * 
     * @param array  the array to remove the element from, may not be <code>null</code>
     * @param index  the position of the element to be removed
     * @return A new array containing the existing elements except the element
     *         at the specified position.
     * @throws IndexOutOfBoundsException if the index is out of range 
     * (index < 0 || index >= array.length), or if the array is <code>null</code>.
     * @since 2.1
     */
    private static Object remove(Object array, int index) {
        int length = getLength(array);
        if (index < 0 || index >= length) {
            throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + length);
        }
        
        Object result = Array.newInstance(array.getClass().getComponentType(), length - 1);
        System.arraycopy(array, 0, result, 0, index);
        if (index < length - 1) {
            System.arraycopy(array, index + 1, result, index, length - index - 1);
        }
        
        return result;
    }
    
}
