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 *
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package org.hsqldb.lib;

import java.lang.reflect.Array;

Collection of static methods for operations on arrays
Author:
Fred Toussi (fredt@users dot sourceforge.net)
Version:
2.5.0
Since:
1.7.2/**
 * Collection of static methods for operations on arrays
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.5.0
 * @since 1.7.2
 */
public class ArrayUtil {

    public static final int        CLASS_CODE_BYTE    = 'B';
    public static final int        CLASS_CODE_CHAR    = 'C';
    public static final int        CLASS_CODE_DOUBLE  = 'D';
    public static final int        CLASS_CODE_FLOAT   = 'F';
    public static final int        CLASS_CODE_INT     = 'I';
    public static final int        CLASS_CODE_LONG    = 'J';
    public static final int        CLASS_CODE_OBJECT  = 'L';
    public static final int        CLASS_CODE_SHORT   = 'S';
    public static final int        CLASS_CODE_BOOLEAN = 'Z';
    private static IntValueHashMap classCodeMap       = new IntValueHashMap();

    static {
        classCodeMap.put(byte.class, ArrayUtil.CLASS_CODE_BYTE);
        classCodeMap.put(char.class, ArrayUtil.CLASS_CODE_SHORT);
        classCodeMap.put(short.class, ArrayUtil.CLASS_CODE_SHORT);
        classCodeMap.put(int.class, ArrayUtil.CLASS_CODE_INT);
        classCodeMap.put(long.class, ArrayUtil.CLASS_CODE_LONG);
        classCodeMap.put(float.class, ArrayUtil.CLASS_CODE_FLOAT);
        classCodeMap.put(double.class, ArrayUtil.CLASS_CODE_DOUBLE);
        classCodeMap.put(boolean.class, ArrayUtil.CLASS_CODE_BOOLEAN);
        classCodeMap.put(Object.class, ArrayUtil.CLASS_CODE_OBJECT);
    }

    
Returns a distinct int code for each primitive type and for all Object types.
/**
     * Returns a distinct int code for each primitive type and for all Object types.
     */
    static int getClassCode(Class cla) {

        if (!cla.isPrimitive()) {
            return ArrayUtil.CLASS_CODE_OBJECT;
        }

        return classCodeMap.get(cla, -1);
    }

    
Clears an area of the given array of the given type.
/**
     * Clears an area of the given array of the given type.
     */
    public static void clearArray(int type, Object data, int from, int to) {

        switch (type) {

            case ArrayUtil.CLASS_CODE_BYTE : {
                byte[] array = (byte[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_CHAR : {
                char[] array = (char[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_SHORT : {
                short[] array = (short[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_INT : {
                int[] array = (int[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_LONG : {
                long[] array = (long[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_FLOAT : {
                float[] array = (float[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_DOUBLE : {
                double[] array = (double[]) data;

                while (--to >= from) {
                    array[to] = 0;
                }

                return;
            }
            case ArrayUtil.CLASS_CODE_BOOLEAN : {
                boolean[] array = (boolean[]) data;

                while (--to >= from) {
                    array[to] = false;
                }

                return;
            }
            default : {
                Object[] array = (Object[]) data;

                while (--to >= from) {
                    array[to] = null;
                }

                return;
            }
        }
    }

    
Moves the contents of an array to allow both addition and removal of
elements. Used arguments must be in range.
Params:
type – class type of the array
array – the array
usedElements – count of elements of array in use
index – point at which to add or remove elements
count – number of elements to add or remove/**
     * Moves the contents of an array to allow both addition and removal of
     * elements. Used arguments must be in range.
     *
     * @param type class type of the array
     * @param array the array
     * @param usedElements count of elements of array in use
     * @param index point at which to add or remove elements
     * @param count number of elements to add or remove
     */
    public static void adjustArray(int type, Object array, int usedElements,
                                   int index, int count) {

        if (index >= usedElements || count == 0) {
            return;
        }

        int newCount = usedElements + count;
        int source;
        int target;
        int size;

        if (count >= 0) {
            source = index;
            target = index + count;
            size   = usedElements - index;
        } else {
            source = index - count;
            target = index;
            size   = usedElements - index + count;
        }

        if (size > 0) {
            System.arraycopy(array, source, array, target, size);
        }

        if (count < 0) {
            clearArray(type, array, newCount, usedElements);
        }
    }

    
Basic sort for small arrays of int.
/**
     * Basic sort for small arrays of int.
     */
    public static void sortArray(int[] array) {

        boolean swapped;

        do {
            swapped = false;

            for (int i = 0; i < array.length - 1; i++) {
                if (array[i] > array[i + 1]) {
                    int temp = array[i + 1];

                    array[i + 1] = array[i];
                    array[i]     = temp;
                    swapped      = true;
                }
            }
        } while (swapped);
    }

    
 Basic find for small arrays of Object.
/**
     *  Basic find for small arrays of Object.
     */
    public static int find(Object[] array, Object object) {

        for (int i = 0; i < array.length; i++) {
            if (array[i] == object) {

                // handles both nulls
                return i;
            }

            if (object != null && object.equals(array[i])) {
                return i;
            }
        }

        return -1;
    }

    
 Basic find for small arrays of int.
/**
     *  Basic find for small arrays of int.
     */
    public static int find(int[] array, int value) {

        for (int i = 0; i < array.length; i++) {
            if (array[i] == value) {
                return i;
            }
        }

        return -1;
    }

    public static int find(short[] array, int value) {

        for (int i = 0; i < array.length; i++) {
            if (array[i] == value) {
                return i;
            }
        }

        return -1;
    }

    public static int find(short[] array, int value, int offset, int count) {

        for (int i = offset; i < offset + count; i++) {
            if (array[i] == value) {
                return i;
            }
        }

        return -1;
    }

    
 Finds the first element of the array that is not equal to the given value.
/**
     *  Finds the first element of the array that is not equal to the given value.
     */
    public static int findNot(int[] array, int value) {

        for (int i = 0; i < array.length; i++) {
            if (array[i] != value) {
                return i;
            }
        }

        return -1;
    }

    
Returns true if arra and arrb contain the same set of integers, not
necessarily in the same order. This implies the arrays are of the same
length.
/**
     * Returns true if arra and arrb contain the same set of integers, not
     * necessarily in the same order. This implies the arrays are of the same
     * length.
     */
    public static boolean areEqualSets(int[] arra, int[] arrb) {
        return arra.length == arrb.length
               && ArrayUtil.haveEqualSets(arra, arrb, arra.length);
    }

    
For full == true returns true if arra and arrb are identical (have the
same length and contain the same integers in the same sequence).
For full == false returns the result
of haveEqualArrays(arra,arrb,count)
For full == true, the array lengths must be the same as count
/**
     * For full == true returns true if arra and arrb are identical (have the
     * same length and contain the same integers in the same sequence).
     *
     * For full == false returns the result
     * of haveEqualArrays(arra,arrb,count)
     *
     * For full == true, the array lengths must be the same as count
     *
     */
    public static boolean areEqual(int[] arra, int[] arrb, int count,
                                   boolean full) {

        if (ArrayUtil.haveEqualArrays(arra, arrb, count)) {
            if (full) {
                return arra.length == arrb.length && count == arra.length;
            }

            return true;
        }

        return false;
    }

    
Returns true if the first count elements of arra and arrb are identical
sets of integers (not necessarily in the same order).
/**
     * Returns true if the first count elements of arra and arrb are identical
     * sets of integers (not necessarily in the same order).
     *
     */
    public static boolean haveEqualSets(int[] arra, int[] arrb, int count) {

        if (ArrayUtil.haveEqualArrays(arra, arrb, count)) {
            return true;
        }

        if (count > arra.length || count > arrb.length) {
            return false;
        }

        if (count == 1) {
            return arra[0] == arrb[0];
        }

        int[] tempa = (int[]) resizeArray(arra, count);
        int[] tempb = (int[]) resizeArray(arrb, count);

        sortArray(tempa);
        sortArray(tempb);

        for (int j = 0; j < count; j++) {
            if (tempa[j] != tempb[j]) {
                return false;
            }
        }

        return true;
    }

    
Returns true if the first count elements of arra and arrb are identical
subarrays of integers
/**
     * Returns true if the first count elements of arra and arrb are identical
     * subarrays of integers
     *
     */
    public static boolean haveEqualArrays(int[] arra, int[] arrb, int count) {

        if (count > arra.length || count > arrb.length) {
            return false;
        }

        for (int j = 0; j < count; j++) {
            if (arra[j] != arrb[j]) {
                return false;
            }
        }

        return true;
    }

    
Returns true if the first count elements of arra and arrb are identical
subarrays of Objects
/**
     * Returns true if the first count elements of arra and arrb are identical
     * subarrays of Objects
     *
     */
    public static boolean haveEqualArrays(Object[] arra, Object[] arrb,
                                          int count) {

        if (count > arra.length || count > arrb.length) {
            return false;
        }

        for (int j = 0; j < count; j++) {
            if (arra[j] != arrb[j]) {
                if (arra[j] == null || !arra[j].equals(arrb[j])) {
                    return false;
                }
            }
        }

        return true;
    }

    
Returns true if arra and arrb share any element. 

Used for checks for any overlap between two arrays of column indexes.
/**
     * Returns true if arra and arrb share any element. <p>
     *
     * Used for checks for any overlap between two arrays of column indexes.
     */
    public static boolean haveCommonElement(int[] arra, int[] arrb) {

        if (arra == null || arrb == null) {
            return false;
        }

        for (int i = 0; i < arra.length; i++) {
            int c = arra[i];

            for (int j = 0; j < arrb.length; j++) {
                if (c == arrb[j]) {
                    return true;
                }
            }
        }

        return false;
    }

    
Returns an int[] containing elements shared between the two arrays
arra and arrb. The arrays contain sets (no value is repeated).
Used to find the overlap between two arrays of column indexes.
Ordering of the result arrays will be the same as in array
a. The method assumes that each index is only listed
once in the two input arrays.

e.g.



The arrays
int []arra
=
{2,11,5,8}
int []arrb
=
{20,8,10,11,28,12}
will result in:
int []arrc
=
{11,8}

Params:
arra – int[]; first column indexes
arrb – int[]; second column indexes
Returns:
int[] common indexes or null if there is no overlap./**
     * Returns an int[] containing elements shared between the two arrays
     * arra and arrb. The arrays contain sets (no value is repeated).
     *
     * Used to find the overlap between two arrays of column indexes.
     * Ordering of the result arrays will be the same as in array
     * a. The method assumes that each index is only listed
     * once in the two input arrays.
     * <p>
     * e.g.
     * </p>
     * <code>
     * <table width="90%" bgcolor="lightblue">
     * <tr><td colspane="3">The arrays</td></tr>
     * <tr><td>int []arra</td><td>=</td><td>{2,11,5,8}</td></tr>
     * <tr><td>int []arrb</td><td>=</td><td>{20,8,10,11,28,12}</td></tr>
     * <tr><td colspane="3">will result in:</td></tr>
     * <tr><td>int []arrc</td><td>=</td><td>{11,8}</td></tr>
     * </table>
     *
     * @param arra int[]; first column indexes
     * @param arrb int[]; second column indexes
     * @return int[] common indexes or <code>null</code> if there is no overlap.
     */
    public static int[] commonElements(int[] arra, int[] arrb) {

        int[] c = null;
        int   n = countCommonElements(arra, arrb);

        if (n > 0) {
            c = new int[n];

            int k = 0;

            for (int i = 0; i < arra.length; i++) {
                for (int j = 0; j < arrb.length; j++) {
                    if (arra[i] == arrb[j]) {
                        c[k++] = arra[i];
                    }
                }
            }
        }

        return c;
    }

    
Returns the number of elements shared between the two arrays containing
sets.

Return the number of elements shared by two column index arrays.
This method assumes that each of these arrays contains a set (each
element index is listed only once in each index array). Otherwise the
returned number will NOT represent the number of unique column indexes
shared by both index array.
Params:
arra – int[]; first array of column indexes.
arrb – int[]; second array of column indexes
Returns:
int; number of elements shared by a and b/**
     * Returns the number of elements shared between the two arrays containing
     * sets.<p>
     *
     * Return the number of elements shared by two column index arrays.
     * This method assumes that each of these arrays contains a set (each
     * element index is listed only once in each index array). Otherwise the
     * returned number will NOT represent the number of unique column indexes
     * shared by both index array.
     *
     * @param arra int[]; first array of column indexes.
     *
     * @param arrb int[]; second array of column indexes
     *
     * @return int; number of elements shared by <code>a</code> and <code>b</code>
     */
    public static int countCommonElements(int[] arra, int[] arrb) {

        int k = 0;

        for (int i = 0; i < arra.length; i++) {
            for (int j = 0; j < arrb.length; j++) {
                if (arra[i] == arrb[j]) {
                    k++;

                    break;
                }
            }
        }

        return k;
    }

    public static int countCommonElements(Object[] arra, int alen,
                                          Object[] arrb) {

        int k = 0;

        for (int i = 0; i < alen; i++) {
            for (int j = 0; j < arrb.length; j++) {
                if (arra[i] == arrb[j]) {
                    k++;

                    break;
                }
            }
        }

        return k;
    }

    
Returns the count of elements in arra from position start that are
sequentially equal to the elements of arrb.
/**
     * Returns the count of elements in arra from position start that are
     * sequentially equal to the elements of arrb.
     */
    public static int countSameElements(byte[] arra, int start, byte[] arrb) {

        int k     = 0;
        int limit = arra.length - start;

        if (limit > arrb.length) {
            limit = arrb.length;
        }

        for (int i = 0; i < limit; i++) {
            if (arra[i + start] == arrb[i]) {
                k++;
            } else {
                break;
            }
        }

        return k;
    }

    
Returns the count of elements in arra from position start that are
sequentially equal to the elements of arrb.
/**
     * Returns the count of elements in arra from position start that are
     * sequentially equal to the elements of arrb.
     */
    public static int countSameElements(char[] arra, int start, char[] arrb) {

        int k     = 0;
        int limit = arra.length - start;

        if (limit > arrb.length) {
            limit = arrb.length;
        }

        for (int i = 0; i < limit; i++) {
            if (arra[i + start] == arrb[i]) {
                k++;
            } else {
                break;
            }
        }

        return k;
    }

    
Returns the count of elements in arra from position start that are
sequentially equal to the elements of arrb.
/**
     * Returns the count of elements in arra from position start that are
     * sequentially equal to the elements of arrb.
     */
    public static int countSameElements(int[] arra, int start, int[] arrb) {

        int k     = 0;
        int limit = arra.length - start;

        if (limit > arrb.length) {
            limit = arrb.length;
        }

        for (int i = 0; i < limit; i++) {
            if (arra[i + start] == arrb[i]) {
                k++;
            } else {
                break;
            }
        }

        return k;
    }

    
Returns the count of elements in arra that are smaller than the value.
/**
     * Returns the count of elements in arra that are smaller than the value.
     */
    public static int countSmallerElements(int[] arra, int value) {

        int count = 0;

        for (int i = 0; i < arra.length; i++) {
            if (arra[i] < value) {
                count++;
            }
        }

        return count;
    }

    
Returns the count of elements in arra that are smaller/equal than the
value.
/**
     * Returns the count of elements in arra that are smaller/equal than the
     * value.
     */
    public static int countSmallerEqualElements(int[] arra, int value) {

        int count = 0;

        for (int i = 0; i < arra.length; i++) {
            if (arra[i] <= value) {
                count++;
            }
        }

        return count;
    }

    
Returns an array that contains all the elements of the two arrays.
/**
     * Returns an array that contains all the elements of the two arrays.
     */
    public static int[] union(int[] arra, int[] arrb) {

        int newSize = arra.length + arrb.length
                      - ArrayUtil.countCommonElements(arra, arrb);

        if (newSize > arra.length && newSize > arrb.length) {
            int[] arrn = (int[]) ArrayUtil.resizeArray(arrb, newSize);
            int   pos  = arrb.length;

            mainloop:
            for (int i = 0; i < arra.length; i++) {
                for (int j = 0; j < arrb.length; j++) {
                    if (arra[i] == arrb[j]) {
                        continue mainloop;
                    }
                }

                arrn[pos++] = arra[i];
            }

            return arrn;
        }

        return arra.length > arrb.length ? arra
                                         : arrb;
    }

    
Returns the index of the first occurrence of arrb in arra. Or -1 if not found.
/**
     * Returns the index of the first occurrence of arrb in arra. Or -1 if not found.
     */
    public static int find(byte[] arra, int start, int limit, byte[] arrb) {

        int k = start;

        limit = limit - arrb.length + 1;

        int value = arrb[0];

        for (; k < limit; k++) {
            if (arra[k] == value) {
                if (arrb.length == 1) {
                    return k;
                }

                if (containsAt(arra, k, arrb)) {
                    return k;
                }
            }
        }

        return -1;
    }

    
Returns an index into arra (or -1) where the character is not in the
charset byte array.
/**
     * Returns an index into arra (or -1) where the character is not in the
     * charset byte array.
     */
    public static int findNotIn(byte[] arra, int start, int limit,
                                byte[] byteSet) {

        mainloop:
        for (int k = start; k < limit; k++) {
            for (int i = 0; i < byteSet.length; i++) {
                if (arra[k] == byteSet[i]) {
                    continue mainloop;
                }
            }

            return k;
        }

        return -1;
    }

    
Returns an index into arra (or -1) where the character is in the
byteSet byte array.
/**
     * Returns an index into arra (or -1) where the character is in the
     * byteSet byte array.
     */
    public static int findIn(byte[] arra, int start, int limit,
                             byte[] byteSet) {

        for (int k = start; k < limit; k++) {
            for (int i = 0; i < byteSet.length; i++) {
                if (arra[k] == byteSet[i]) {
                    return k;
                }
            }
        }

        return -1;
    }

    
Returns the index of b or c in arra. Or -1 if not found.
/**
     * Returns the index of b or c in arra. Or -1 if not found.
     */
    public static int find(byte[] arra, int start, int limit, int b, int c) {

        int k = 0;

        for (; k < limit; k++) {
            if (arra[k] == b || arra[k] == c) {
                return k;
            }
        }

        return -1;
    }

    
Set elements of arrb true if their indexes appear in arrb.
/**
     * Set elements of arrb true if their indexes appear in arrb.
     */
    public static int[] booleanArrayToIntIndexes(boolean[] arrb) {

        int count = 0;

        for (int i = 0; i < arrb.length; i++) {
            if (arrb[i]) {
                count++;
            }
        }

        int[] intarr = new int[count];

        count = 0;

        for (int i = 0; i < arrb.length; i++) {
            if (arrb[i]) {
                intarr[count++] = i;
            }
        }

        return intarr;
    }

    
Set elements of arrb true if their indexes appear in arrb.
/**
     * Set elements of arrb true if their indexes appear in arrb.
     */
    public static void intIndexesToBooleanArray(int[] arra, boolean[] arrb) {

        for (int i = 0; i < arra.length; i++) {
            if (arra[i] < arrb.length) {
                arrb[arra[i]] = true;
            }
        }
    }

    
Return array of indexes of boolean elements that are true.
/**
     * Return array of indexes of boolean elements that are true.
     */
    public static int countStartIntIndexesInBooleanArray(int[] arra,
            boolean[] arrb) {

        int k = 0;

        for (int i = 0; i < arra.length; i++) {
            if (arrb[arra[i]]) {
                k++;
            } else {
                break;
            }
        }

        return k;
    }

    public static void orBooleanArray(boolean[] source, boolean[] dest) {

        for (int i = 0; i < dest.length; i++) {
            dest[i] |= source[i];
        }
    }

    
Returns true if all indexes and no other positions are true in
arrb.
arra must have no duplicates.
/**
     * Returns true if all indexes and no other positions are true in
     * arrb.
     * arra must have no duplicates.
     */
    public static boolean areAllIntIndexesAsBooleanArray(int[] arra,
            boolean[] arrb) {

        for (int i = 0; i < arra.length; i++) {
            if (arrb[arra[i]]) {
                continue;
            }

            return false;
        }

        return arra.length == countTrueElements(arrb);
    }

    public static boolean areAllIntIndexesInBooleanArray(int[] arra,
            boolean[] arrb) {

        for (int i = 0; i < arra.length; i++) {
            if (arrb[arra[i]]) {
                continue;
            }

            return false;
        }

        return true;
    }

    public static boolean isAnyIntIndexInBooleanArray(int[] arra,
            boolean[] arrb) {

        for (int i = 0; i < arra.length; i++) {
            if (arrb[arra[i]]) {
                return true;
            }
        }

        return false;
    }

    
Return true if for each true element in arrb, the corresponding
element in arra is true
/**
     * Return true if for each true element in arrb, the corresponding
     * element in arra is true
     */
    public static boolean containsAllTrueElements(boolean[] arra,
            boolean[] arrb) {

        for (int i = 0; i < arra.length; i++) {
            if (arrb[i] && !arra[i]) {
                return false;
            }
        }

        return true;
    }

    
Return count of true elements in array
/**
     * Return count of true elements in array
     */
    public static int countTrueElements(boolean[] arra) {

        int count = 0;

        for (int i = 0; i < arra.length; i++) {
            if (arra[i]) {
                count++;
            }
        }

        return count;
    }

    
Determines if the array has a null column for any of the positions given
in the rowColMap array.
/**
     * Determines if the array has a null column for any of the positions given
     * in the rowColMap array.
     */
    public static boolean hasNull(Object[] array, int[] columnMap) {

        int count = columnMap.length;

        for (int i = 0; i < count; i++) {
            if (array[columnMap[i]] == null) {
                return true;
            }
        }

        return false;
    }

    public static boolean hasAllNull(Object[] array, int[] columnMap) {

        int count = columnMap.length;

        for (int i = 0; i < count; i++) {
            if (array[columnMap[i]] != null) {
                return false;
            }
        }

        return true;
    }

    
Returns true if arra from position start contains all elements of arrb
in sequential order.
/**
     * Returns true if arra from position start contains all elements of arrb
     * in sequential order.
     */
    public static boolean containsAt(byte[] arra, int start, byte[] arrb) {
        return countSameElements(arra, start, arrb) == arrb.length;
    }

    
Returns the count of elements in arra from position start that are
among the elements of arrb. Stops at any element not in arrb.
/**
     * Returns the count of elements in arra from position start that are
     * among the elements of arrb. Stops at any element not in arrb.
     */
    public static int countStartElementsAt(byte[] arra, int start,
                                           byte[] arrb) {

        int k = 0;

        mainloop:
        for (int i = start; i < arra.length; i++) {
            for (int j = 0; j < arrb.length; j++) {
                if (arra[i] == arrb[j]) {
                    k++;

                    continue mainloop;
                }
            }

            break;
        }

        return k;
    }

    
Returns true if arra from position start contains all elements of arrb
in sequential order.
/**
     * Returns true if arra from position start contains all elements of arrb
     * in sequential order.
     */
    public static boolean containsAt(char[] arra, int start, char[] arrb) {
        return countSameElements(arra, start, arrb) == arrb.length;
    }

    
Returns the count of elements in arra from position start that are not
among the elements of arrb.
/**
     * Returns the count of elements in arra from position start that are not
     * among the elements of arrb.
     *
     */
    public static int countNonStartElementsAt(byte[] arra, int start,
            byte[] arrb) {

        int k = 0;

        mainloop:
        for (int i = start; i < arra.length; i++) {
            for (int j = 0; j < arrb.length; j++) {
                if (arra[i] == arrb[j]) {
                    break mainloop;
                }
            }

            k++;
        }

        return k;
    }

    
Byte arrays source and dest each begin at an offset in the common space.
If there is an overlap between dest and the first sourceLength elements of
the source, the overlapping elements are copied to dest. Returns count
of copied bytes.
/**
     * Byte arrays source and dest each begin at an offset in the common space.
     * If there is an overlap between dest and the first sourceLength elements of
     * the source, the overlapping elements are copied to dest. Returns count
     * of copied bytes.
     */
    public static int copyBytes(long sourceOffset, byte[] source,
                                int sourceOff, int sourceLength,
                                long destOffset, byte[] dest, int destLength) {

        if (sourceOff >= source.length) {
            return 0;
        }

        if (sourceOff + sourceLength > source.length) {
            sourceLength = source.length - sourceOff;
        }

        if (destLength > dest.length) {
            destLength = dest.length;
        }

        if (sourceOffset + sourceOff >= destOffset + destLength
                || sourceOffset + sourceOff + sourceLength <= destOffset) {
            return 0;
        }

        long sourceIndex = destOffset - sourceOffset;
        long destIndex   = 0;
        int  sourceLimit = sourceOff + sourceLength;

        if (sourceIndex >= 0) {
            if (sourceIndex < sourceOff) {
                sourceIndex = sourceOff;
            }
        } else {
            destIndex   = -sourceIndex + sourceOff;
            sourceIndex = sourceOff;
        }

        sourceLength = sourceLimit - (int) sourceIndex;

        if (sourceLength > destLength - destIndex) {
            sourceLength = destLength - (int) destIndex;
        }

        System.arraycopy(source, (int) sourceIndex, dest, (int) destIndex,
                         sourceLength);

        return sourceLength;
    }

    
Copy the source to dest, returning dest or an enlarged array of result is
larger than dest.
/**
     * Copy the source to dest, returning dest or an enlarged array of result is
     * larger than dest.
     */
    public static byte[] copyBytes(byte[] source, byte[] dest,
                                   int destOffset) {

        if (source.length + destOffset > dest.length) {
            byte[] newDest = new byte[source.length + destOffset];

            System.arraycopy(dest, 0, newDest, 0, dest.length);

            dest = newDest;
        }

        System.arraycopy(source, 0, dest, destOffset, source.length);

        return dest;
    }

    
Convenience wrapper for System.arraycopy().
/**
     * Convenience wrapper for System.arraycopy().
     */
    public static void copyArray(Object source, Object dest, int count) {
        System.arraycopy(source, 0, dest, 0, count);
    }

    public static void copyMoveSegment(Object source, Object dest, int size,
                                       int index, int segmentSize,
                                       int destIndex) {

        boolean forward   = index < destIndex;
        int     sliceSize = forward ? index
                                    : destIndex;

        System.arraycopy(source, 0, dest, 0, sliceSize);

        sliceSize = forward ? size - destIndex - segmentSize
                            : size - index - segmentSize;

        int sliceIndex = forward ? destIndex + segmentSize
                                 : index + segmentSize;

        System.arraycopy(source, sliceIndex, dest, sliceIndex, sliceSize);
        System.arraycopy(source, index, dest, destIndex, segmentSize);

        sliceSize  = Math.abs(index - destIndex);
        sliceIndex = forward ? index + segmentSize
                             : destIndex;

        int targetSliceIndex = forward ? index
                                       : destIndex + segmentSize;

        System.arraycopy(source, sliceIndex, dest, targetSliceIndex,
                         sliceSize);
    }

    
Returns a range of elements of source from start to end of the array.
/**
     * Returns a range of elements of source from start to end of the array.
     */
    public static int[] arraySlice(int[] source, int start, int count) {

        int[] slice = new int[count];

        System.arraycopy(source, start, slice, 0, count);

        return slice;
    }

    
Fills part of the array with a value.
/**
     * Fills part of the array with a value.
     */
    public static void fillArray(char[] array, int offset, char value) {

        int to = array.length;

        while (--to >= offset) {
            array[to] = value;
        }
    }

    
Fills part of the array with a value.
/**
     * Fills part of the array with a value.
     */
    public static void fillArray(byte[] array, int offset, byte value) {

        int to = array.length;

        while (--to >= offset) {
            array[to] = value;
        }
    }

    
Fills the array with a value.
/**
     * Fills the array with a value.
     */
    public static void fillArray(Object[] array, Object value) {

        int to = array.length;

        while (--to >= 0) {
            array[to] = value;
        }
    }

    
Fills the int array with a value
/**
     * Fills the int array with a value
     */
    public static void fillArray(int[] array, int value) {

        int to = array.length;

        while (--to >= 0) {
            array[to] = value;
        }
    }

    
Fills the double array with a value
/**
     * Fills the double array with a value
     */
    public static void fillArray(double[] array, double value) {

        int to = array.length;

        while (--to >= 0) {
            array[to] = value;
        }
    }

    
Fills the int array with a value
/**
     * Fills the int array with a value
     */
    public static void fillArray(boolean[] array, boolean value) {

        int to = array.length;

        while (--to >= 0) {
            array[to] = value;
        }
    }

    
Returns a duplicates of an array.
/**
     * Returns a duplicates of an array.
     */
    public static Object duplicateArray(Object source) {

        int size = Array.getLength(source);
        Object newarray =
            Array.newInstance(source.getClass().getComponentType(), size);

        System.arraycopy(source, 0, newarray, 0, size);

        return newarray;
    }

    
Returns the given array if newsize is the same as existing.
Returns a new array of given size, containing as many elements of
the original array as it can hold.
/**
     * Returns the given array if newsize is the same as existing.
     * Returns a new array of given size, containing as many elements of
     * the original array as it can hold.
     */
    public static Object resizeArrayIfDifferent(Object source, int newsize) {

        int oldsize = Array.getLength(source);

        if (oldsize == newsize) {
            return source;
        }

        Object newarray =
            Array.newInstance(source.getClass().getComponentType(), newsize);

        if (oldsize < newsize) {
            newsize = oldsize;
        }

        System.arraycopy(source, 0, newarray, 0, newsize);

        return newarray;
    }

    
Returns a new array of given size, containing as many elements of
the original array as it can hold. N.B. Always returns a new array
even if newsize parameter is the same as the old size.
/**
     * Returns a new array of given size, containing as many elements of
     * the original array as it can hold. N.B. Always returns a new array
     * even if newsize parameter is the same as the old size.
     */
    public static Object resizeArray(Object source, int newsize) {

        Object newarray =
            Array.newInstance(source.getClass().getComponentType(), newsize);
        int oldsize = Array.getLength(source);

        if (oldsize < newsize) {
            newsize = oldsize;
        }

        System.arraycopy(source, 0, newarray, 0, newsize);

        return newarray;
    }

    
Returns an array containing the elements of parameter source, with one
element removed or added. Parameter adjust {-1, +1} indicates the
operation. Parameter colindex indicates the position at which an element
is removed or added. Parameter addition is an Object to add when
adjust is +1.
/**
     * Returns an array containing the elements of parameter source, with one
     * element removed or added. Parameter adjust {-1, +1} indicates the
     * operation. Parameter colindex indicates the position at which an element
     * is removed or added. Parameter addition is an Object to add when
     * adjust is +1.
     */
    public static Object toAdjustedArray(Object source, Object addition,
                                         int colindex, int adjust) {

        int newsize = Array.getLength(source) + adjust;
        Object newarray =
            Array.newInstance(source.getClass().getComponentType(), newsize);

        copyAdjustArray(source, newarray, addition, colindex, adjust);

        return newarray;
    }

    
Copies elements of source to dest. If adjust is -1 the element at
colindex is not copied. If adjust is +1 that element is filled with
the Object addition. All the rest of the elements in source are
shifted left or right accordingly when they are copied. If adjust is 0
the addition is copied over the element at colindex.
No checks are performed on array sizes and an exception is thrown
if they are not consistent with the other arguments.
/**
     * Copies elements of source to dest. If adjust is -1 the element at
     * colindex is not copied. If adjust is +1 that element is filled with
     * the Object addition. All the rest of the elements in source are
     * shifted left or right accordingly when they are copied. If adjust is 0
     * the addition is copied over the element at colindex.
     *
     * No checks are performed on array sizes and an exception is thrown
     * if they are not consistent with the other arguments.
     */
    public static void copyAdjustArray(Object source, Object dest,
                                       Object addition, int colindex,
                                       int adjust) {

        int length = Array.getLength(source);

        if (colindex < 0) {
            System.arraycopy(source, 0, dest, 0, length);

            return;
        }

        System.arraycopy(source, 0, dest, 0, colindex);

        if (adjust == 0) {
            int endcount = length - colindex - 1;

            Array.set(dest, colindex, addition);

            if (endcount > 0) {
                System.arraycopy(source, colindex + 1, dest, colindex + 1,
                                 endcount);
            }
        } else if (adjust < 0) {
            int endcount = length - colindex - 1;

            if (endcount > 0) {
                System.arraycopy(source, colindex + 1, dest, colindex,
                                 endcount);
            }
        } else {
            int endcount = length - colindex;

            Array.set(dest, colindex, addition);

            if (endcount > 0) {
                System.arraycopy(source, colindex, dest, colindex + 1,
                                 endcount);
            }
        }
    }

    
Similar to single slot adjusted copy, with multiple slots added or
removed. The colindex array is the ordered lists the slots to be added or
removed. The adjust argument can be {-1, +1) for remove or add.
No checks are performed on array sizes and no exception is thrown
if they are not consistent with the other arguments.
/**
     * Similar to single slot adjusted copy, with multiple slots added or
     * removed. The colindex array is the ordered lists the slots to be added or
     * removed. The adjust argument can be {-1, +1) for remove or add.
     *
     * No checks are performed on array sizes and no exception is thrown
     * if they are not consistent with the other arguments.
     */
    public static void copyAdjustArray(Object[] source, Object[] dest,
                                       int[] colindex, int adjust) {

        if (adjust == 0) {
            System.arraycopy(source, 0, dest, 0, source.length);

            return;
        }

        for (int i = 0, j = 0, counter = 0;
                i < source.length && j < dest.length; i++, j++) {
            int adjustPos = -1;

            if (counter < colindex.length) {
                adjustPos = colindex[counter];

                if (adjust > 0) {
                    if (adjustPos == j) {
                        j++;
                        counter++;
                    }
                } else {
                    if (adjustPos == i) {
                        i++;
                        counter++;
                    }
                }
            }

            dest[j] = source[i];
        }
    }

    
Returns a new array with the elements in collar adjusted to reflect
changes at colindex. 

Each element in collarr represents an index into another array
otherarr. 

colindex is the index at which an element is added or removed.
Each element in the result array represents the new,
adjusted index. 

For each element of collarr that represents an index equal to
colindex and adjust is -1, the result will not contain that element
and will be shorter than collar by one element.
Params:
colarr – the source array
colindex – index at which to perform adjustment
adjust – +1, 0 or -1
Returns:
new, adjusted array/**
     * Returns a new array with the elements in collar adjusted to reflect
     * changes at colindex. <p>
     *
     * Each element in collarr represents an index into another array
     * otherarr. <p>
     *
     * colindex is the index at which an element is added or removed.
     * Each element in the result array represents the new,
     * adjusted index. <p>
     *
     * For each element of collarr that represents an index equal to
     * colindex and adjust is -1, the result will not contain that element
     * and will be shorter than collar by one element.
     *
     * @param  colarr the source array
     * @param  colindex index at which to perform adjustment
     * @param  adjust +1, 0 or -1
     * @return new, adjusted array
     */
    public static int[] toAdjustedColumnArray(int[] colarr, int colindex,
            int adjust) {

        if (colarr == null) {
            return null;
        }

        if (colindex < 0) {
            return colarr;
        }

        int[] intarr = new int[colarr.length];
        int   j      = 0;

        for (int i = 0; i < colarr.length; i++) {
            if (colarr[i] > colindex) {
                intarr[j] = colarr[i] + adjust;

                j++;
            } else if (colarr[i] == colindex) {
                if (adjust < 0) {

                    // skip an element from colarr
                } else {
                    intarr[j] = colarr[i] + adjust;

                    j++;
                }
            } else {
                intarr[j] = colarr[i];

                j++;
            }
        }

        if (colarr.length != j) {
            int[] newarr = new int[j];

            copyArray(intarr, newarr, j);

            return newarr;
        }

        return intarr;
    }

    
similar to the function with signle colindex, but with multiple
adjustments.
/**
     * similar to the function with signle colindex, but with multiple
     * adjustments.
     */
    public static int[] toAdjustedColumnArray(int[] colarr, int[] colindex,
            int adjust) {

        if (colarr == null) {
            return null;
        }

        int[] intarr = new int[colarr.length];
        int   j      = 0;

        if (adjust == 0) {
            for (int i = 0; i < colarr.length; i++) {
                intarr[i] = colarr[i];
            }
        } else if (adjust < 0) {
            for (int i = 0; i < colarr.length; i++) {
                int count = countSmallerElements(colindex, colarr[i]);

                intarr[i] = colarr[i] - count;
            }
        } else {
            for (int i = 0; i < colarr.length; i++) {
                int count = countSmallerEqualElements(colindex, colarr[i]);

                intarr[i] = colarr[i] + count;
            }
        }

        return intarr;
    }

    
 Copies some elements of row into newRow by using columnMap as
 the list of indexes into row. 

 columnMap and newRow are of equal length and are normally
 shorter than row. 

 @param row the source array
 @param columnMap the list of indexes into row
 @param newRow the destination array
/**
     *  Copies some elements of row into newRow by using columnMap as
     *  the list of indexes into row. <p>
     *
     *  columnMap and newRow are of equal length and are normally
     *  shorter than row. <p>
     *
     *  @param row the source array
     *  @param columnMap the list of indexes into row
     *  @param newRow the destination array
     */
    public static void projectRow(Object[] row, int[] columnMap,
                                  Object[] newRow) {

        for (int i = 0; i < columnMap.length; i++) {
            newRow[i] = row[columnMap[i]];
        }
    }

    public static void projectRow(int[] row, int[] columnMap, int[] newRow) {

        for (int i = 0; i < columnMap.length; i++) {
            newRow[i] = row[columnMap[i]];
        }
    }

    
 As above but copies in reverse direction. 

 @param row the target array
 @param columnMap the list of indexes into row
 @param newRow the source array
/**
     *  As above but copies in reverse direction. <p>
     *
     *  @param row the target array
     *  @param columnMap the list of indexes into row
     *  @param newRow the source array
     */
    public static void projectRowReverse(Object[] row, int[] columnMap,
                                         Object[] newRow) {

        for (int i = 0; i < columnMap.length; i++) {
            row[columnMap[i]] = newRow[i];
        }
    }

/*
    public static void copyColumnValues(int[] row, int[] colindex,
                                        int[] colobject) {

        for (int i = 0; i < colindex.length; i++) {
            colobject[i] = row[colindex[i]];
        }
    }

    public static void copyColumnValues(boolean[] row, int[] colindex,
                                        boolean[] colobject) {

        for (int i = 0; i < colindex.length; i++) {
            colobject[i] = row[colindex[i]];
        }
    }

    public static void copyColumnValues(byte[] row, int[] colindex,
                                        byte[] colobject) {

        for (int i = 0; i < colindex.length; i++) {
            colobject[i] = row[colindex[i]];
        }
    }
*/
    public static void projectMap(int[] mainMap, int[] subMap,
                                  int[] newSubMap) {

        for (int i = 0; i < subMap.length; i++) {
            for (int j = 0; j < mainMap.length; j++) {
                if (subMap[i] == mainMap[j]) {
                    newSubMap[i] = j;

                    break;
                }
            }
        }
    }

    public static void reorderMaps(int[] mainMap, int[] firstMap,
                                   int[] secondMap) {

        for (int i = 0; i < mainMap.length; i++) {
            for (int j = i; j < firstMap.length; j++) {
                if (mainMap[i] == firstMap[j]) {
                    int temp = firstMap[i];

                    firstMap[i]  = firstMap[j];
                    firstMap[j]  = temp;
                    temp         = secondMap[i];
                    secondMap[i] = secondMap[j];
                    secondMap[j] = temp;

                    break;
                }
            }
        }
    }

    public static void fillSequence(int[] colindex) {

        for (int i = 0; i < colindex.length; i++) {
            colindex[i] = i;
        }
    }

    public static char[] byteArrayToChars(byte[] bytes) {
        return byteArrayToChars(bytes, bytes.length);
    }

    public static char[] byteArrayToChars(byte[] bytes, int bytesLength) {

        char[] chars = new char[bytesLength / 2];

        for (int i = 0, j = 0; j < chars.length; i += 2, j++) {
            chars[j] = (char) ((bytes[i] << 8) + (bytes[i + 1] & 0xff));
        }

        return chars;
    }

    public static byte[] charArrayToBytes(char[] chars) {
        return charArrayToBytes(chars, chars.length);
    }

    public static byte[] charArrayToBytes(char[] chars, int length) {

        byte[] bytes = new byte[length * 2];

        for (int i = 0, j = 0; j < length; i += 2, j++) {
            int c = chars[j];

            bytes[i]     = (byte) (c >> 8);
            bytes[i + 1] = (byte) c;
        }

        return bytes;
    }

    
Returns true if char argument is in array.
/**
     * Returns true if char argument is in array.
     */
    public static boolean isInSortedArray(char ch, char[] array) {

        if (array.length == 0 || ch < array[0]
                || ch > array[array.length - 1]) {
            return false;
        }

        int low  = 0;
        int high = array.length;
        int mid  = 0;

        while (low < high) {
            mid = (low + high) >>> 1;

            if (ch < array[mid]) {
                high = mid;
            } else if (ch > array[mid]) {
                low = mid + 1;
            } else {
                return true;
            }
        }

        return false;
    }

    
returns true if arra contains all elements of arrb
Params:
arra – Object[]
arrb – Object[]
Returns:
boolean/**
     * returns true if arra contains all elements of arrb
     *
     * @param arra Object[]
     * @param arrb Object[]
     * @return boolean
     */
    public static boolean containsAll(Object[] arra, Object[] arrb) {

        mainLoop:
        for (int i = 0; i < arrb.length; i++) {
            for (int j = 0; j < arra.length; j++) {
                if (arrb[i] == arra[j] || arrb[i].equals(arra[j])) {
                    continue mainLoop;
                }
            }

            return false;
        }

        return true;
    }

    
returns true if arra contains any element of arrb
Params:
arra – Object[]
arrb – Object[]
Returns:
boolean/**
     * returns true if arra contains any element of arrb
     *
     * @param arra Object[]
     * @param arrb Object[]
     * @return boolean
     */
    public static boolean containsAny(Object[] arra, Object[] arrb) {

        mainLoop:
        for (int i = 0; i < arrb.length; i++) {
            for (int j = 0; j < arra.length; j++) {
                if (arrb[i] == arra[j] || arrb[i].equals(arra[j])) {
                    return true;
                }
            }
        }

        return false;
    }

    
returns true if arra contains all elements of arrb
Params:
arra – int[]
arrb – int[]
Returns:
boolean/**
     * returns true if arra contains all elements of arrb
     *
     * @param arra int[]
     * @param arrb int[]
     * @return boolean
     */
    public static boolean containsAll(int[] arra, int[] arrb) {

        mainLoop:
        for (int i = 0; i < arrb.length; i++) {
            for (int j = 0; j < arra.length; j++) {
                if (arrb[i] == arra[j]) {
                    continue mainLoop;
                }
            }

            return false;
        }

        return true;
    }

    
returns true if arra contains all elements of arrb at its start
Params:
arra – int[]
arrb – int[]
Returns:
boolean/**
     * returns true if arra contains all elements of arrb at its start
     *
     * @param arra int[]
     * @param arrb int[]
     * @return boolean
     */
    public static boolean containsAllAtStart(int[] arra, int[] arrb) {

        if (arrb.length > arra.length) {
            return false;
        }

        mainLoop:
        for (int i = 0; i < arra.length; i++) {
            if (i == arrb.length) {
                return true;
            }

            for (int j = 0; j < arrb.length; j++) {
                if (arra[i] == arrb[j]) {
                    continue mainLoop;
                }
            }

            return false;
        }

        return true;
    }

    
converts two longs to a byte[]
Params:
hi – long
lo – long
Returns:
byte[]/**
     * converts two longs to a byte[]
     *
     * @param hi long
     * @param lo long
     * @return byte[]
     */
    public static byte[] toByteArray(long hi, long lo) {

        byte[] bytes = new byte[16];
        int    count = 0;
        int    v;

        while (count < 16) {
            if (count == 0) {
                v = (int) (hi >>> 32);
            } else if (count == 4) {
                v = (int) hi;
            } else if (count == 8) {
                v = (int) (lo >>> 32);
            } else {
                v = (int) lo;
            }

            bytes[count++] = (byte) (v >>> 24);
            bytes[count++] = (byte) (v >>> 16);
            bytes[count++] = (byte) (v >>> 8);
            bytes[count++] = (byte) v;
        }

        return bytes;
    }

    public static long byteSequenceToLong(byte[] bytes, int pos) {

        long val = 0;

        for (int i = 0; i < 8; i++) {
            long b = bytes[pos + i] & 0xff;

            val += (b << ((7 - i) * 8));
        }

        return val;
    }

    
Compares two arrays. Returns -1, 0, +1. If one array is shorter and
all the elements are equal to the other's elements, -1 is returned.
/**
     * Compares two arrays. Returns -1, 0, +1. If one array is shorter and
     * all the elements are equal to the other's elements, -1 is returned.
     */
    public static int compare(byte[] a, byte[] b) {
        return compare(a, 0, a.length, b, 0, b.length);
    }

    public static int compare(byte[] a, int aOffset, int aLength, byte[] b,
                              int bOffset, int bLength) {

        int length = aLength;

        if (length > bLength) {
            length = bLength;
        }

        for (int i = 0; i < length; i++) {
            if (a[aOffset + i] == b[bOffset + i]) {
                continue;
            }

            return (((int) a[aOffset + i]) & 0xff)
                   > (((int) b[bOffset + i]) & 0xff) ? 1
                                                     : -1;
        }

        if (aLength == bLength) {
            return 0;
        }

        return aLength < bLength ? -1
                                 : 1;
    }

    
uses 2**scale form and returns a multiple of unit that is larger or equal to value
/**
     * uses 2**scale form and returns a multiple of unit that is larger or equal to value
     */
    public static long getBinaryMultipleCeiling(long value, long unit) {

        long newSize = value & -unit;

        if (newSize != value) {
            newSize += unit;
        }

        return newSize;
    }

    
uses 2**scale form and returns a multiple of this that is larger or equal to value
/**
     * uses 2**scale form and returns a multiple of this that is larger or equal to value
     */
    public static long getBinaryNormalisedCeiling(long value, int scale) {

        long mask    = 0xffffffffffffffffL << scale;
        long newSize = value & mask;

        if (newSize != value) {
            newSize = newSize + (1L << scale);
        }

        return newSize;
    }

    
returns the largest value that is a power of 2 and larger or equal to value
/**
     * returns the largest value that is a power of 2 and larger or equal to value
     */
    public static long getBinaryNormalisedCeiling(long value) {

        long newSize = 2;

        while (newSize < value) {
            newSize <<= 1;
        }

        return newSize;
    }

    
returns true if log2 n is in the range (0, max)
/**
     * returns true if log2 n is in the range (0, max)
     */
    public static boolean isTwoPower(int n, int max) {

        for (int i = 0; i <= max; i++) {
            if ((n & 1) != 0) {
                return n == 1;
            }

            n >>= 1;
        }

        return false;
    }

    
returns the largest value that is 0 or a power of 2 and is smaller or equal to n
/**
     * returns the largest value that is 0 or a power of 2 and is smaller or equal to n
     */
    public static int getTwoPowerFloor(int n) {

        int shift = getTwoPowerScale(n);

        if (shift == 0) {
            return 0;
        }

        return 1 << shift;
    }

    
returns the log2 of largest value that is 0 or a power of 2 and is smaller or equal to n
/**
     * returns the log2 of largest value that is 0 or a power of 2 and is smaller or equal to n
     */
    public static int getTwoPowerScale(int n) {

        int shift = 0;

        if (n == 0) {
            return 0;
        }

        for (int i = 0; i < 32; i++) {
            if ((n & 1) != 0) {
                shift = i;
            }

            n >>= 1;
        }

        return shift;
    }

    
a and b must be both positive
returns (a / b) or (a / b) + 1 if remainder is larger than zero
/**
     * a and b must be both positive
     * returns (a / b) or (a / b) + 1 if remainder is larger than zero
     */
    public static int cdiv(int a, int b) {

        int c = a / b;

        if (a % b != 0) {
            c++;
        }

        return c;
    }

    public static long cdiv(long a, long b) {

        long c = a / b;

        if (a % b != 0) {
            c++;
        }

        return c;
    }
}