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/* Copyright (c) 2001-2004, The HSQL Development Group
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the HSQL Development Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.hsqldb.lib;
import java.lang.reflect.Array;
/**
* Collection of static methods for operations on arrays
*
* @author fredt@users
* @version 1.7.2
*/
public class ArrayUtil {
final public static int CLASS_CODE_BYTE = 'B';
final public static int CLASS_CODE_CHAR = 'C';
final public static int CLASS_CODE_DOUBLE = 'D';
final public static int CLASS_CODE_FLOAT = 'F';
final public static int CLASS_CODE_INT = 'I';
final public static int CLASS_CODE_LONG = 'J';
final public static int CLASS_CODE_OBJECT = 'L';
final public static int CLASS_CODE_SHORT = 'S';
final public static 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.
*/
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.
*/
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 : {
byte[] array = (byte[]) 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.
*
* @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
* @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) {
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.
*/
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.
*/
public static int find(Object array[], Object object) {
for (int i = 0; i < array.length; i++) {
if (array[i] == object) {
// hadles both nulls
return i;
}
if (object != null && object.equals(array[i])) {
return i;
}
}
return -1;
}
/**
* 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;
}
/**
* 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.
*/
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
*
*/
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).
*
*/
public static boolean haveEqualSets(int[] arra, int[] arrb, int count) {
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
*
*/
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
*
*/
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 the first bcount elements of arrb share any
* element.
*
* Used for checks for any overlap between two arrays of column indexes.
*/
public static boolean haveCommonElement(int[] arra, int[] arrb,
int bcount) {
for (int i = 0; i < arra.length; i++) {
int c = arra[i];
for (int j = 0; j < bcount; 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} |
*
*
* @param arra int[]; first column indexes
*
* @param arrb int[]; second column indexes
*
* @return int[] common indexes or null if there is no overlap.
*
* @short Return the overlap between two arrays of column indexes.
*/
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.
*
* @param arra int[]; first array of column indexes.
*
* @param arrb int[]; second array of column indexes
*
* @return int; number of elements shared by a and b
*/
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++;
}
}
}
return k;
}
/**
* 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 index of the first occurence of arrb in arra. Or -1 if not found.
*/
public static int find(byte[] arra, int start, int limit, byte[] arrb) {
int k = 0;
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.
*/
public static int findNotIn(byte[] arra, int start, int limit,
byte[] charset) {
int k = 0;
for (; k < limit; k++) {
for (int i = 0; i < charset.length; i++) {
if (arra[k] == charset[i]) {
continue;
}
}
return k;
}
return -1;
}
/**
* Returns an index into arra (or -1) where the character is in the
* charset byte array.
*/
public static int findIn(byte[] arra, int start, int limit,
byte[] charset) {
int k = 0;
for (; k < limit; k++) {
for (int i = 0; i < charset.length; i++) {
if (arra[k] == charset[i]) {
return k;
}
}
}
return -1;
}
/**
* 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.
*/
public static void intIndexesToBooleanArray(int[] arra, boolean[] arrb) {
int k = 0;
for (int i = 0; i < arra.length; i++) {
if (arra[i] < arrb.length) {
arrb[arra[i]] = 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) {
int k = 0;
for (int i = 0; i < arra.length; i++) {
if (arrb[i] &&!arra[i]) {
return false;
}
}
return true;
}
/**
* 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.
*/
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 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;
}
/**
* Convenience wrapper for System.arraycopy().
*/
public static void copyArray(Object source, Object dest, int count) {
System.arraycopy(source, 0, dest, 0, count);
}
/**
* 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 the array with a value.
*/
public static void fillArray(Object[] array, Object value) {
int to = array.length;
while (--to >= 0) {
array[to] = value;
}
}
/**
* 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 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.
*/
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
* only elements up to colindex are copied.
*
* No checks are perfomed 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);
System.arraycopy(source, 0, dest, 0, colindex);
if (adjust == 0) {
return;
} 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);
}
}
}
/**
* 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.
*
* @param colarr the source array
* @param colindex index at which to perform adjustement
* @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;
}
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;
}
/**
* Copies some elements of row into colobject by using colindex as
* the list of indexes into row.
*
* colindex and colobject are of equal length and are normally
* shorter than row.
*
* @param row the source array
* @param colindex the list of indexes into row
* @param colobject the destination array
*/
public static void copyColumnValues(Object row[], int colindex[],
Object colobject[]) {
for (int i = 0; i < colindex.length; i++) {
colobject[i] = row[colindex[i]];
}
}
/*
public static void main(String[] args) {
int[] a = new int[] {
23, 11, 37, 7, 1, 5
};
int[] b = new int[] {
1, 3, 7, 11, 13, 17, 19, 3, 1
};
int[] c = toAdjustedColumnArray(a, 7, -1);
int[] d = toAdjustedColumnArray(b, 11, 1);
int[] e = new int[a.length];
copyArray(a, e, a.length);
sortArray(e);
int[] f = new int[b.length];
copyArray(b, f, b.length);
sortArray(f);
boolean x = haveEqualSets(a, e, a.length);
boolean y = haveEqualSets(b, f, b.length);
System.out.print("test passed: ");
System.out.print(x == true && y == true && c.length == a.length - 1
&& d.length == b.length);
}
*/
}
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