/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Imported by CG 20101225 based on Apache Harmony ("enhanced") revision 929253.
*/
package java.util;
import java.io.Serializable;
import java.lang.reflect.Array;
/**
* {@code Arrays} contains static methods which operate on arrays.
*
* @since 1.2
*/
public class Arrays {
/* Specifies when to switch to insertion sort */
private static final int SIMPLE_LENGTH = 7;
private static class ArrayList extends AbstractList implements
List, Serializable, RandomAccess {
private static final long serialVersionUID = -2764017481108945198L;
private final Object[] a;
ArrayList(Object[] storage) {
if (storage == null) {
throw new NullPointerException();
}
a = storage;
}
public boolean contains(Object object) {
if (object != null) {
for (int i = 0; i < a.length; ++i) {
if (object.equals(a[i])) {
return true;
}
}
} else {
for (int i = 0; i < a.length; ++i) {
if (a[i] == null) {
return true;
}
}
}
return false;
}
public Object get(int location) {
try {
return a[location];
} catch (ArrayIndexOutOfBoundsException e) {
throw new IndexOutOfBoundsException();
}
}
public int indexOf(Object object) {
if (object != null) {
for (int i = 0; i < a.length; i++) {
if (object.equals(a[i])) {
return i;
}
}
} else {
for (int i = 0; i < a.length; i++) {
if (a[i] == null) {
return i;
}
}
}
return -1;
}
public int lastIndexOf(Object object) {
if (object != null) {
for (int i = a.length - 1; i >= 0; i--) {
if (object.equals(a[i])) {
return i;
}
}
} else {
for (int i = a.length - 1; i >= 0; i--) {
if (a[i] == null) {
return i;
}
}
}
return -1;
}
public Object set(int location, Object object) {
try {
Object result = a[location];
a[location] = object;
return result;
} catch (ArrayIndexOutOfBoundsException e) {
throw new IndexOutOfBoundsException();
} catch (ArrayStoreException e) {
throw new ClassCastException();
}
}
public int size() {
return a.length;
}
public Object[] toArray() {
return (Object[]) a.clone();
}
public Object[] toArray(Object[] contents) {
int size = size();
if (size > contents.length) {
Class ct = contents.getClass().getComponentType();
contents = (Object[]) Array.newInstance(ct, size);
}
System.arraycopy(a, 0, contents, 0, size);
if (size < contents.length) {
contents[size] = null;
}
return contents;
}
}
private Arrays() {
/* empty */
}
/**
* Returns a {@code List} of the objects in the specified array. The size of the
* {@code List} cannot be modified, i.e. adding and removing are unsupported, but
* the elements can be set. Setting an element modifies the underlying
* array.
*
* @param array
* the array.
* @return a {@code List} of the elements of the specified array.
*/
public static List asList(Object[] array) {
return new ArrayList(array);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code byte} array to search.
* @param value
* the {@code byte} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(byte[] array, byte value) {
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (value > array[mid]) {
low = mid + 1;
} else if (value == array[mid]) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (value < array[mid] ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code char} array to search.
* @param value
* the {@code char} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(char[] array, char value) {
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (value > array[mid]) {
low = mid + 1;
} else if (value == array[mid]) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (value < array[mid] ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code double} array to search.
* @param value
* the {@code double} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(double[] array, double value) {
long longBits = Double.doubleToLongBits(value);
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (lessThan(array[mid], value)) {
low = mid + 1;
} else if (longBits == Double.doubleToLongBits(array[mid])) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (lessThan(value, array[mid]) ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code float} array to search.
* @param value
* the {@code float} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(float[] array, float value) {
int intBits = Float.floatToIntBits(value);
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (lessThan(array[mid], value)) {
low = mid + 1;
} else if (intBits == Float.floatToIntBits(array[mid])) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (lessThan(value, array[mid]) ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code int} array to search.
* @param value
* the {@code int} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(int[] array, int value) {
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (value > array[mid]) {
low = mid + 1;
} else if (value == array[mid]) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (value < array[mid] ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code long} array to search.
* @param value
* the {@code long} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(long[] array, long value) {
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (value > array[mid]) {
low = mid + 1;
} else if (value == array[mid]) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (value < array[mid] ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code Object} array to search.
* @param object
* the {@code Object} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
* @throws ClassCastException
* if an element in the array or the search element does not
* implement {@code Comparable}, or cannot be compared to each other.
*/
public static int binarySearch(Object[] array, Object object) {
if (array.length == 0) {
return -1;
}
int low = 0, mid = 0, high = array.length - 1, result = 0;
while (low <= high) {
mid = (low + high) >>> 1;
if ((result = ((Comparable)array[mid]).compareTo(object)) < 0){
low = mid + 1;
} else if (result == 0) {
return mid;
} else {
high = mid - 1;
}
}
return -mid - (result >= 0 ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array using the {@code Comparator} to compare elements.
* Searching in an unsorted array has an undefined result. It's also
* undefined which element is found if there are multiple occurrences of the
* same element.
*
* @param array
* the sorted array to search
* @param object
* the element to find
* @param comparator
* the {@code Comparator} sued to compare the elements.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
* @throws ClassCastException
* if an element in the array cannot be compared to the search element
* using the {@code Comparator}.
*/
public static int binarySearch(Object[] array, Object object,
Comparator comparator) {
if (comparator == null) {
return binarySearch(array, object);
}
int low = 0, mid = 0, high = array.length - 1, result = 0;
while (low <= high) {
mid = (low + high) >>> 1;
if ((result = comparator.compare(array[mid], object)) < 0) {
low = mid + 1;
} else if (result == 0) {
return mid;
} else {
high = mid - 1;
}
}
return -mid - (result >= 0 ? 1 : 2);
}
/**
* Performs a binary search for the specified element in the specified
* ascending sorted array. Searching in an unsorted array has an undefined
* result. It's also undefined which element is found if there are multiple
* occurrences of the same element.
*
* @param array
* the sorted {@code short} array to search.
* @param value
* the {@code short} element to find.
* @return the non-negative index of the element, or a negative index which
* is {@code -index - 1} where the element would be inserted.
*/
public static int binarySearch(short[] array, short value) {
int low = 0, mid = -1, high = array.length - 1;
while (low <= high) {
mid = (low + high) >>> 1;
if (value > array[mid]) {
low = mid + 1;
} else if (value == array[mid]) {
return mid;
} else {
high = mid - 1;
}
}
if (mid < 0) {
return -1;
}
return -mid - (value < array[mid] ? 1 : 2);
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code byte} array to fill.
* @param value
* the {@code byte} element.
*/
public static void fill(byte[] array, byte value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code byte} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code byte} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(byte[] array, int start, int end, byte value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code short} array to fill.
* @param value
* the {@code short} element.
*/
public static void fill(short[] array, short value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code short} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code short} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(short[] array, int start, int end, short value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code char} array to fill.
* @param value
* the {@code char} element.
*/
public static void fill(char[] array, char value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code char} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code char} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(char[] array, int start, int end, char value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code int} array to fill.
* @param value
* the {@code int} element.
*/
public static void fill(int[] array, int value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code int} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code int} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(int[] array, int start, int end, int value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code long} array to fill.
* @param value
* the {@code long} element.
*/
public static void fill(long[] array, long value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code long} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code long} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(long[] array, int start, int end, long value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code float} array to fill.
* @param value
* the {@code float} element.
*/
public static void fill(float[] array, float value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code float} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code float} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(float[] array, int start, int end, float value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code double} array to fill.
* @param value
* the {@code double} element.
*/
public static void fill(double[] array, double value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code double} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code double} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(double[] array, int start, int end, double value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code boolean} array to fill.
* @param value
* the {@code boolean} element.
*/
public static void fill(boolean[] array, boolean value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code boolean} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code boolean} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(boolean[] array, int start, int end, boolean value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Fills the specified array with the specified element.
*
* @param array
* the {@code Object} array to fill.
* @param value
* the {@code Object} element.
*/
public static void fill(Object[] array, Object value) {
for (int i = 0; i < array.length; i++) {
array[i] = value;
}
}
/**
* Fills the specified range in the array with the specified element.
*
* @param array
* the {@code Object} array to fill.
* @param start
* the first index to fill.
* @param end
* the last + 1 index to fill.
* @param value
* the {@code Object} element.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void fill(Object[] array, int start, int end, Object value) {
checkBounds(array.length, start, end);
for (int i = start; i < end; i++) {
array[i] = value;
}
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code boolean} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Boolean}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(boolean[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
// 1231, 1237 are hash code values for boolean value
hashCode = 31 * hashCode + (array[i] ? 1231 : 1237);
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* not-null {@code int} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Integer}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(int[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
// the hash code value for integer value is integer value itself
hashCode = 31 * hashCode + array[i];
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code short} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Short}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(short[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
// the hash code value for short value is its integer value
hashCode = 31 * hashCode + array[i];
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code char} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Character}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(char[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
// the hash code value for char value is its integer value
hashCode = 31 * hashCode + array[i];
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code byte} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Byte}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(byte[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
// the hash code value for byte value is its integer value
hashCode = 31 * hashCode + array[i];
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code long} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Long}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(long[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
long elementValue = array[i];
/*
* the hash code value for long value is (int) (value ^ (value >>>
* 32))
*/
hashCode = 31 * hashCode
+ (int) (elementValue ^ (elementValue >>> 32));
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code float} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Float}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(float[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
/*
* the hash code value for float value is
* Float.floatToIntBits(value)
*/
hashCode = 31 * hashCode + Float.floatToIntBits(array[i]);
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. For any two
* {@code double} arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the
* {@link List#hashCode()}} method which is invoked on a {@link List}}
* containing a sequence of {@link Double}} instances representing the
* elements of array in the same order. If the array is {@code null}, the return
* value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(double[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
long v = Double.doubleToLongBits(array[i]);
/*
* the hash code value for double value is (int) (v ^ (v >>> 32))
* where v = Double.doubleToLongBits(value)
*/
hashCode = 31 * hashCode + (int) (v ^ (v >>> 32));
}
return hashCode;
}
/**
* Returns a hash code based on the contents of the given array. If the
* array contains other arrays as its elements, the hash code is based on
* their identities not their contents. So it is acceptable to invoke this
* method on an array that contains itself as an element, either directly or
* indirectly.
* <p>
* For any two arrays {@code a} and {@code b}, if
* {@code Arrays.equals(a, b)} returns {@code true}, it means
* that the return value of {@code Arrays.hashCode(a)} equals
* {@code Arrays.hashCode(b)}.
* <p>
* The value returned by this method is the same value as the method
* Arrays.asList(array).hashCode(). If the array is {@code null}, the return value
* is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int hashCode(Object[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
int elementHashCode;
if (array[i] == null) {
elementHashCode = 0;
} else {
elementHashCode = (array[i]).hashCode();
}
hashCode = 31 * hashCode + elementHashCode;
}
return hashCode;
}
/**
* Returns a hash code based on the "deep contents" of the given array. If
* the array contains other arrays as its elements, the hash code is based
* on their contents not their identities. So it is not acceptable to invoke
* this method on an array that contains itself as an element, either
* directly or indirectly.
* <p>
* For any two arrays {@code a} and {@code b}, if
* {@code Arrays.deepEquals(a, b)} returns {@code true}, it
* means that the return value of {@code Arrays.deepHashCode(a)} equals
* {@code Arrays.deepHashCode(b)}.
* <p>
* The computation of the value returned by this method is similar to that
* of the value returned by {@link List#hashCode()}} invoked on a
* {@link List}} containing a sequence of instances representing the
* elements of array in the same order. The difference is: If an element e
* of array is itself an array, its hash code is computed by calling the
* appropriate overloading of {@code Arrays.hashCode(e)} if e is an array of a
* primitive type, or by calling {@code Arrays.deepHashCode(e)} recursively if e is
* an array of a reference type. The value returned by this method is the
* same value as the method {@code Arrays.asList(array).hashCode()}. If the array is
* {@code null}, the return value is 0.
*
* @param array
* the array whose hash code to compute.
* @return the hash code for {@code array}.
*/
public static int deepHashCode(Object[] array) {
if (array == null) {
return 0;
}
int hashCode = 1;
for (int i = 0; i < array.length; ++i) {
int elementHashCode = deepHashCodeElement(array[i]);
hashCode = 31 * hashCode + elementHashCode;
}
return hashCode;
}
private static int deepHashCodeElement(Object element) {
Class cl;
if (element == null) {
return 0;
}
cl = element.getClass().getComponentType();
if (cl == null) {
return element.hashCode();
}
/*
* element is an array
*/
if (!cl.isPrimitive()) {
return deepHashCode((Object[]) element);
}
if (cl.equals(int.class)) {
return hashCode((int[]) element);
}
if (cl.equals(char.class)) {
return hashCode((char[]) element);
}
if (cl.equals(boolean.class)) {
return hashCode((boolean[]) element);
}
if (cl.equals(byte.class)) {
return hashCode((byte[]) element);
}
if (cl.equals(long.class)) {
return hashCode((long[]) element);
}
if (cl.equals(float.class)) {
return hashCode((float[]) element);
}
if (cl.equals(double.class)) {
return hashCode((double[]) element);
}
return hashCode((short[]) element);
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code byte} array.
* @param array2
* the second {@code byte} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(byte[] array1, byte[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code short} array.
* @param array2
* the second {@code short} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(short[] array1, short[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code char} array.
* @param array2
* the second {@code char} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(char[] array1, char[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code int} array.
* @param array2
* the second {@code int} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(int[] array1, int[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code long} array.
* @param array2
* the second {@code long} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(long[] array1, long[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays. The values are compared in the same manner as
* {@code Float.equals()}.
*
* @param array1
* the first {@code float} array.
* @param array2
* the second {@code float} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
* @see Float#equals(Object)
*/
public static boolean equals(float[] array1, float[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (Float.floatToIntBits(array1[i]) != Float
.floatToIntBits(array2[i])) {
return false;
}
}
return true;
}
/**
* Compares the two arrays. The values are compared in the same manner as
* {@code Double.equals()}.
*
* @param array1
* the first {@code double} array.
* @param array2
* the second {@code double} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
* @see Double#equals(Object)
*/
public static boolean equals(double[] array1, double[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (Double.doubleToLongBits(array1[i]) != Double
.doubleToLongBits(array2[i])) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code boolean} array.
* @param array2
* the second {@code boolean} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal, {@code false} otherwise.
*/
public static boolean equals(boolean[] array1, boolean[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
if (array1[i] != array2[i]) {
return false;
}
}
return true;
}
/**
* Compares the two arrays.
*
* @param array1
* the first {@code Object} array.
* @param array2
* the second {@code Object} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal according to {@code equals()}, {@code false} otherwise.
*/
public static boolean equals(Object[] array1, Object[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
Object e1 = array1[i], e2 = array2[i];
if (!(e1 == null ? e2 == null : e1.equals(e2))) {
return false;
}
}
return true;
}
/**
* Returns {@code true} if the two given arrays are deeply equal to one another.
* Unlike the method {@code equals(Object[] array1, Object[] array2)}, this method
* is appropriate for use for nested arrays of arbitrary depth.
* <p>
* Two array references are considered deeply equal if they are both {@code null},
* or if they refer to arrays that have the same length and the elements at
* each index in the two arrays are equal.
* <p>
* Two {@code null} elements {@code element1} and {@code element2} are possibly deeply equal if any
* of the following conditions satisfied:
* <p>
* {@code element1} and {@code element2} are both arrays of object reference types, and
* {@code Arrays.deepEquals(element1, element2)} would return {@code true}.
* <p>
* {@code element1} and {@code element2} are arrays of the same primitive type, and the
* appropriate overloading of {@code Arrays.equals(element1, element2)} would return
* {@code true}.
* <p>
* {@code element1 == element2}
* <p>
* {@code element1.equals(element2)} would return {@code true}.
* <p>
* Note that this definition permits {@code null} elements at any depth.
* <p>
* If either of the given arrays contain themselves as elements, the
* behavior of this method is uncertain.
*
* @param array1
* the first {@code Object} array.
* @param array2
* the second {@code Object} array.
* @return {@code true} if both arrays are {@code null} or if the arrays have the
* same length and the elements at each index in the two arrays are
* equal according to {@code equals()}, {@code false} otherwise.
*/
public static boolean deepEquals(Object[] array1, Object[] array2) {
if (array1 == array2) {
return true;
}
if (array1 == null || array2 == null || array1.length != array2.length) {
return false;
}
for (int i = 0; i < array1.length; i++) {
Object e1 = array1[i], e2 = array2[i];
if (!deepEqualsElements(e1, e2)) {
return false;
}
}
return true;
}
private static boolean deepEqualsElements(Object e1, Object e2) {
Class cl1, cl2;
if (e1 == e2) {
return true;
}
if (e1 == null || e2 == null) {
return false;
}
cl1 = e1.getClass().getComponentType();
cl2 = e2.getClass().getComponentType();
if (cl1 != cl2) {
return false;
}
if (cl1 == null) {
return e1.equals(e2);
}
/*
* compare as arrays
*/
if (!cl1.isPrimitive()) {
return deepEquals((Object[]) e1, (Object[]) e2);
}
if (cl1.equals(int.class)) {
return equals((int[]) e1, (int[]) e2);
}
if (cl1.equals(char.class)) {
return equals((char[]) e1, (char[]) e2);
}
if (cl1.equals(boolean.class)) {
return equals((boolean[]) e1, (boolean[]) e2);
}
if (cl1.equals(byte.class)) {
return equals((byte[]) e1, (byte[]) e2);
}
if (cl1.equals(long.class)) {
return equals((long[]) e1, (long[]) e2);
}
if (cl1.equals(float.class)) {
return equals((float[]) e1, (float[]) e2);
}
if (cl1.equals(double.class)) {
return equals((double[]) e1, (double[]) e2);
}
return equals((short[]) e1, (short[]) e2);
}
private static boolean isSame(double double1, double double2) {
// Simple case
if (double1 == double2 && 0.0d != double1) {
return true;
}
// Deal with NaNs
if (Double.isNaN(double1)) {
return Double.isNaN(double2);
}
if (Double.isNaN(double2)) {
return false;
}
// Deal with +0.0 and -0.0
long d1 = Double.doubleToRawLongBits(double1);
long d2 = Double.doubleToRawLongBits(double2);
return d1 == d2;
}
private static boolean lessThan(double double1, double double2) {
// A slightly specialized version of
// Double.compare(double1, double2) < 0.
// Non-zero and non-NaN checking.
if (double1 < double2) {
return true;
}
if (double1 > double2) {
return false;
}
if (double1 == double2 && 0.0d != double1) {
return false;
}
// NaNs are equal to other NaNs and larger than any other double.
if (Double.isNaN(double1)) {
return false;
} else if (Double.isNaN(double2)) {
return true;
}
// Deal with +0.0 and -0.0.
long d1 = Double.doubleToRawLongBits(double1);
long d2 = Double.doubleToRawLongBits(double2);
return d1 < d2;
}
private static boolean isSame(float float1, float float2) {
// Simple case
if (float1 == float2 && 0.0d != float1) {
return true;
}
// Deal with NaNs
if (Float.isNaN(float1)) {
return Float.isNaN(float2);
}
if (Float.isNaN(float2)) {
return false;
}
// Deal with +0.0 and -0.0
int f1 = Float.floatToRawIntBits(float1);
int f2 = Float.floatToRawIntBits(float2);
return f1 == f2;
}
private static boolean lessThan(float float1, float float2) {
// A slightly specialized version of Float.compare(float1, float2) < 0.
// Non-zero and non-NaN checking.
if (float1 < float2) {
return true;
}
if (float1 > float2) {
return false;
}
if (float1 == float2 && 0.0f != float1) {
return false;
}
// NaNs are equal to other NaNs and larger than any other float
if (Float.isNaN(float1)) {
return false;
} else if (Float.isNaN(float2)) {
return true;
}
// Deal with +0.0 and -0.0
int f1 = Float.floatToRawIntBits(float1);
int f2 = Float.floatToRawIntBits(float2);
return f1 < f2;
}
private static int med3(byte[] array, int a, int b, int c) {
byte x = array[a], y = array[b], z = array[c];
return x < y ? (y < z ? b : (x < z ? c : a)) : (y > z ? b : (x > z ? c
: a));
}
private static int med3(char[] array, int a, int b, int c) {
char x = array[a], y = array[b], z = array[c];
return x < y ? (y < z ? b : (x < z ? c : a)) : (y > z ? b : (x > z ? c
: a));
}
private static int med3(double[] array, int a, int b, int c) {
double x = array[a], y = array[b], z = array[c];
return lessThan(x, y) ? (lessThan(y, z) ? b : (lessThan(x, z) ? c : a))
: (lessThan(z, y) ? b : (lessThan(z, x) ? c : a));
}
private static int med3(float[] array, int a, int b, int c) {
float x = array[a], y = array[b], z = array[c];
return lessThan(x, y) ? (lessThan(y, z) ? b : (lessThan(x, z) ? c : a))
: (lessThan(z, y) ? b : (lessThan(z, x) ? c : a));
}
private static int med3(int[] array, int a, int b, int c) {
int x = array[a], y = array[b], z = array[c];
return x < y ? (y < z ? b : (x < z ? c : a)) : (y > z ? b : (x > z ? c
: a));
}
private static int med3(long[] array, int a, int b, int c) {
long x = array[a], y = array[b], z = array[c];
return x < y ? (y < z ? b : (x < z ? c : a)) : (y > z ? b : (x > z ? c
: a));
}
private static int med3(short[] array, int a, int b, int c) {
short x = array[a], y = array[b], z = array[c];
return x < y ? (y < z ? b : (x < z ? c : a)) : (y > z ? b : (x > z ? c
: a));
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code byte} array to be sorted.
*/
public static void sort(byte[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order.
*
* @param array
* the {@code byte} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(byte[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void checkBounds(int arrLength, int start, int end) {
if (start > end) {
throw new IllegalArgumentException("Start index (" + start + ") is greater than end index (" + end + ")");
}
if (start < 0) {
throw new ArrayIndexOutOfBoundsException("Array index out of range: " + start);
}
if (end > arrLength) {
throw new ArrayIndexOutOfBoundsException("Array index out of range: " + end);
}
}
private static void sort(int start, int end, byte[] array) {
byte temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && array[j - 1] > array[j]; j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
byte partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && array[b] <= partionValue) {
if (array[b] == partionValue) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && array[c] >= partionValue) {
if (array[c] == partionValue) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code char} array to be sorted.
*/
public static void sort(char[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order.
*
* @param array
* the {@code char} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(char[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, char[] array) {
char temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && array[j - 1] > array[j]; j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
char partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && array[b] <= partionValue) {
if (array[b] == partionValue) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && array[c] >= partionValue) {
if (array[c] == partionValue) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code double} array to be sorted.
* @see #sort(double[], int, int)
*/
public static void sort(double[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order. The
* values are sorted according to the order imposed by {@code Double.compareTo()}.
*
* @param array
* the {@code double} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
* @see Double#compareTo(Double)
*/
public static void sort(double[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, double[] array) {
double temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && lessThan(array[j], array[j - 1]); j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
double partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && !lessThan(partionValue, array[b])) {
if (isSame(array[b], partionValue)) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && !lessThan(array[c], partionValue)) {
if (isSame(array[c], partionValue)) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code float} array to be sorted.
* @see #sort(float[], int, int)
*/
public static void sort(float[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order. The
* values are sorted according to the order imposed by {@code Float.compareTo()}.
*
* @param array
* the {@code float} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
* @see Float#compareTo(Float)
*/
public static void sort(float[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, float[] array) {
float temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && lessThan(array[j], array[j - 1]); j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
float partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && !lessThan(partionValue, array[b])) {
if (isSame(array[b], partionValue)) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && !lessThan(array[c], partionValue)) {
if (isSame(array[c], partionValue)) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code int} array to be sorted.
*/
public static void sort(int[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order.
*
* @param array
* the {@code int} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(int[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, int[] array) {
int temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && array[j - 1] > array[j]; j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
int partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && array[b] <= partionValue) {
if (array[b] == partionValue) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && array[c] >= partionValue) {
if (array[c] == partionValue) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code long} array to be sorted.
*/
public static void sort(long[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order.
*
* @param array
* the {@code long} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(long[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, long[] array) {
long temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && array[j - 1] > array[j]; j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
long partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && array[b] <= partionValue) {
if (array[b] == partionValue) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && array[c] >= partionValue) {
if (array[c] == partionValue) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
/**
* Sorts the specified array in ascending natural order.
*
* @param array
* the {@code Object} array to be sorted.
* @throws ClassCastException
* if an element in the array does not implement {@code Comparable}
* or if some elements cannot be compared to each other.
* @see #sort(Object[], int, int)
*/
public static void sort(Object[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending natural order. All
* elements must implement the {@code Comparable} interface and must be
* comparable to each other without a {@code ClassCastException} being
* thrown.
*
* @param array
* the {@code Object} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws ClassCastException
* if an element in the array does not implement {@code Comparable}
* or some elements cannot be compared to each other.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(Object[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, Object[] array) {
int length = end - start;
if (length <= 0) {
return;
}
if (array instanceof String[]) {
stableStringSort((String[]) array, start, end);
} else {
Object[] out = new Object[end];
System.arraycopy(array, start, out, start, length);
mergeSort(out, array, start, end);
}
}
/**
* Swaps the elements at the given indices in the array.
*
* @param a -
* the index of one element to be swapped.
* @param b -
* the index of the other element to be swapped.
* @param arr -
* the array in which to swap elements.
*/
private static void swap(int a, int b, Object[] arr) {
Object tmp = arr[a];
arr[a] = arr[b];
arr[b] = tmp;
}
/**
* Performs a sort on the section of the array between the given indices
* using a mergesort with exponential search algorithm (in which the merge
* is performed by exponential search). n*log(n) performance is guaranteed
* and in the average case it will be faster then any mergesort in which the
* merge is performed by linear search.
*
* @param in -
* the array for sorting.
* @param out -
* the result, sorted array.
* @param start
* the start index
* @param end
* the end index + 1
*/
private static void mergeSort(Object[] in, Object[] out, int start,
int end) {
int len = end - start;
// use insertion sort for small arrays
if (len <= SIMPLE_LENGTH) {
for (int i = start + 1; i < end; i++) {
Comparable current = (Comparable) out[i];
Object prev = out[i - 1];
if (current.compareTo(prev) < 0) {
int j = i;
do {
out[j--] = prev;
} while (j > start
&& current.compareTo(prev = out[j - 1]) < 0);
out[j] = current;
}
}
return;
}
int med = (end + start) >>> 1;
mergeSort(out, in, start, med);
mergeSort(out, in, med, end);
// merging
// if arrays are already sorted - no merge
if (((Comparable) in[med - 1]).compareTo(in[med]) <= 0) {
System.arraycopy(in, start, out, start, len);
return;
}
int r = med, i = start;
// use merging with exponential search
do {
Comparable fromVal = (Comparable) in[start];
Comparable rVal = (Comparable) in[r];
if (fromVal.compareTo(rVal) <= 0) {
int l_1 = find(in, rVal, -1, start + 1, med - 1);
int toCopy = l_1 - start + 1;
System.arraycopy(in, start, out, i, toCopy);
i += toCopy;
out[i++] = rVal;
r++;
start = l_1 + 1;
} else {
int r_1 = find(in, fromVal, 0, r + 1, end - 1);
int toCopy = r_1 - r + 1;
System.arraycopy(in, r, out, i, toCopy);
i += toCopy;
out[i++] = fromVal;
start++;
r = r_1 + 1;
}
} while ((end - r) > 0 && (med - start) > 0);
// copy rest of array
if ((end - r) <= 0) {
System.arraycopy(in, start, out, i, med - start);
} else {
System.arraycopy(in, r, out, i, end - r);
}
}
/**
* Performs a sort on the section of the array between the given indices
* using a mergesort with exponential search algorithm (in which the merge
* is performed by exponential search). n*log(n) performance is guaranteed
* and in the average case it will be faster then any mergesort in which the
* merge is performed by linear search.
*
* @param in -
* the array for sorting.
* @param out -
* the result, sorted array.
* @param start
* the start index
* @param end
* the end index + 1
* @param c -
* the comparator to determine the order of the array.
*/
private static void mergeSort(Object[] in, Object[] out, int start,
int end, Comparator c) {
int len = end - start;
// use insertion sort for small arrays
if (len <= SIMPLE_LENGTH) {
for (int i = start + 1; i < end; i++) {
Object current = out[i];
Object prev = out[i - 1];
if (c.compare(prev, current) > 0) {
int j = i;
do {
out[j--] = prev;
} while (j > start
&& (c.compare(prev = out[j - 1], current) > 0));
out[j] = current;
}
}
return;
}
int med = (end + start) >>> 1;
mergeSort(out, in, start, med, c);
mergeSort(out, in, med, end, c);
// merging
// if arrays are already sorted - no merge
if (c.compare(in[med - 1],in[med] ) <= 0) {
System.arraycopy(in, start, out, start, len);
return;
}
int r = med, i = start;
// use merging with exponential search
do {
Object fromVal = in[start];
Object rVal = in[r];
if (c.compare(fromVal, rVal) <= 0) {
int l_1 = find(in, rVal, -1, start + 1, med - 1, c);
int toCopy = l_1 - start + 1;
System.arraycopy(in, start, out, i, toCopy);
i += toCopy;
out[i++] = rVal;
r++;
start = l_1 + 1;
} else {
int r_1 = find(in, fromVal, 0, r + 1, end - 1, c);
int toCopy = r_1 - r + 1;
System.arraycopy(in, r, out, i, toCopy);
i += toCopy;
out[i++] = fromVal;
start++;
r = r_1 + 1;
}
} while ((end - r) > 0 && (med - start) > 0);
// copy rest of array
if ((end - r) <= 0) {
System.arraycopy(in, start, out, i, med - start);
} else {
System.arraycopy(in, r, out, i, end - r);
}
}
/**
* Finds the place in the given range of specified sorted array, where the
* element should be inserted for getting sorted array. Uses exponential
* search algorithm.
*
* @param arr -
* the array with already sorted range
*
* @param val -
* object to be inserted
*
* @param l -
* the start index
*
* @param r -
* the end index
*
* @param bnd -
* possible values 0,-1. "-1" - val is located at index more then
* elements equals to val. "0" - val is located at index less
* then elements equals to val.
*
*/
private static int find(Object[] arr, Comparable val, int bnd, int l, int r) {
int m = l;
int d = 1;
while (m <= r) {
if (val.compareTo(arr[m]) > bnd) {
l = m + 1;
} else {
r = m - 1;
break;
}
m += d;
d <<= 1;
}
while (l <= r) {
m = (l + r) >>> 1;
if (val.compareTo(arr[m]) > bnd) {
l = m + 1;
} else {
r = m - 1;
}
}
return l - 1;
}
/**
* Finds the place of specified range of specified sorted array, where the
* element should be inserted for getting sorted array. Uses exponential
* search algorithm.
*
* @param arr -
* the array with already sorted range
* @param val -
* object to be inserted
* @param l -
* the start index
* @param r -
* the end index
* @param bnd -
* possible values 0,-1. "-1" - val is located at index more then
* elements equals to val. "0" - val is located at index less
* then elements equals to val.
* @param c -
* the comparator used to compare Objects
*/
private static int find(Object[] arr, Object val, int bnd, int l, int r,
Comparator c) {
int m = l;
int d = 1;
while (m <= r) {
if (c.compare(val, arr[m]) > bnd) {
l = m + 1;
} else {
r = m - 1;
break;
}
m += d;
d <<= 1;
}
while (l <= r) {
m = (l + r) >>> 1;
if (c.compare(val, arr[m]) > bnd) {
l = m + 1;
} else {
r = m - 1;
}
}
return l - 1;
}
/*
* returns the median index.
*/
private static int medChar(int a, int b, int c, String[] arr, int id) {
int ac = charAt(arr[a], id);
int bc = charAt(arr[b], id);
int cc = charAt(arr[c], id);
return ac < bc ? (bc < cc ? b : (ac < cc ? c : a))
: (bc < cc ? (ac < cc ? a : c) : b);
}
/*
* Returns the char value at the specified index of string or -1 if the
* index more than the length of this string.
*/
private static int charAt(String str, int i) {
if (i >= str.length()) {
return -1;
}
return str.charAt(i);
}
/**
* Copies object from one array to another array with reverse of objects
* order. Source and destination arrays may be the same.
*
* @param src -
* the source array.
* @param from -
* starting position in the source array.
* @param dst -
* the destination array.
* @param to -
* starting position in the destination array.
* @param len -
* the number of array elements to be copied.
*/
private static void copySwap(Object[] src, int from, Object[] dst, int to,
int len) {
if (src == dst && from + len > to) {
int new_to = to + len - 1;
for (; from < to; from++, new_to--, len--) {
dst[new_to] = src[from];
}
for (; len > 1; from++, new_to--, len -= 2) {
swap(from, new_to, dst);
}
} else {
to = to + len - 1;
for (; len > 0; from++, to--, len--) {
dst[to] = src[from];
}
}
}
/**
* Performs a sort on the given String array. Elements will be re-ordered into
* ascending order.
*
* @param arr -
* the array to sort
* @param start -
* the start index
* @param end -
* the end index + 1
*/
private static void stableStringSort(String[] arr, int start,
int end) {
stableStringSort(arr, arr, new String[end], start, end, 0);
}
/**
* Performs a sort on the given String array. Elements will be re-ordered into
* ascending order. Uses a stable ternary quick sort algorithm.
*
* @param arr -
* the array to sort
* @param src -
* auxiliary array
* @param dst -
* auxiliary array
* @param start -
* the start index
* @param end -
* the end index + 1
* @param chId -
* index of char for current sorting
*/
private static void stableStringSort(String[] arr, String[] src,
String[] dst, int start, int end, int chId) {
int length = end - start;
// use insertion sort for small arrays
if (length < SIMPLE_LENGTH) {
if (src == arr) {
for (int i = start + 1; i < end; i++) {
String current = arr[i];
String prev = arr[i - 1];
if (current.compareTo(prev) < 0) {
int j = i;
do {
arr[j--] = prev;
} while (j > start
&& current.compareTo(prev = arr[j - 1]) < 0);
arr[j] = current;
}
}
} else {
int actualEnd = end - 1;
dst[start] = src[actualEnd--];
for (int i = start + 1; i < end; i++, actualEnd--) {
String current = src[actualEnd];
String prev;
int j = i;
while (j > start
&& current.compareTo(prev = dst[j - 1]) < 0) {
dst[j--] = prev;
}
dst[j] = current;
}
}
return;
}
// Approximate median
int s;
int mid = start + length / 2;
int lo = start;
int hi = end - 1;
if (length > 40) {
s = length / 8;
lo = medChar(lo, lo + s, lo + s * 2, src, chId);
mid = medChar(mid - s, mid, mid + s, src, chId);
hi = medChar(hi, hi - s, hi - s * 2, src, chId);
}
mid = medChar(lo, mid, hi, src, chId);
// median found
// create 4 pointers <a (in star of src) ,
// =b(in start of dst), >c (in end of dst)
// i - current element;
int midVal = charAt(src[mid], chId);
int a, b, c;
a = b = start;
c = end - 1;
int cmp;
for (int i = start; i < end; i++) {
String el = src[i];
cmp = charAt(el, chId) - midVal;
if (cmp < 0) {
src[a] = el;
a++;
} else if (cmp > 0) {
dst[c] = el;
c--;
} else {
dst[b] = el;
b++;
}
}
s = b - start;
if (s > 0) {
if (arr == src) {
System.arraycopy(dst, start, arr, a, s);
} else {
copySwap(dst, start, arr, a, s);
}
if (b >= end && midVal == -1) {
return;
}
stableStringSort(arr, arr, arr == dst ? src : dst, a, a + s,
chId + 1);
}
s = a - start;
if (s > 0) {
stableStringSort(arr, src, dst, start, a, chId);
}
c++;
s = end - c;
if (s > 0) {
stableStringSort(arr, dst, src, c, end, chId);
}
}
/**
* Sorts the specified range in the array using the specified {@code Comparator}.
* All elements must be comparable to each other without a
* {@code ClassCastException} being thrown.
*
* @param array
* the {@code Object} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @param comparator
* the {@code Comparator}.
* @throws ClassCastException
* if elements in the array cannot be compared to each other
* using the {@code Comparator}.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(Object[] array, int start, int end,
Comparator comparator) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array, comparator);
}
private static void sort(int start, int end, Object[] array,
Comparator comparator) {
if (comparator == null) {
sort(start, end, array);
} else {
int length = end - start;
Object[] out = new Object[end];
System.arraycopy(array, start, out, start, length);
mergeSort(out, array, start, end, comparator);
}
}
/**
* Sorts the specified array using the specified {@code Comparator}. All elements
* must be comparable to each other without a {@code ClassCastException} being thrown.
*
* @param array
* the {@code Object} array to be sorted.
* @param comparator
* the {@code Comparator}.
* @throws ClassCastException
* if elements in the array cannot be compared to each other
* using the {@code Comparator}.
*/
public static void sort(Object[] array, Comparator comparator) {
sort(0, array.length, array, comparator);
}
/**
* Sorts the specified array in ascending numerical order.
*
* @param array
* the {@code short} array to be sorted.
*/
public static void sort(short[] array) {
sort(0, array.length, array);
}
/**
* Sorts the specified range in the array in ascending numerical order.
*
* @param array
* the {@code short} array to be sorted.
* @param start
* the start index to sort.
* @param end
* the last + 1 index to sort.
* @throws IllegalArgumentException
* if {@code start > end}.
* @throws ArrayIndexOutOfBoundsException
* if {@code start < 0} or {@code end > array.length}.
*/
public static void sort(short[] array, int start, int end) {
if (array == null) {
throw new NullPointerException();
}
checkBounds(array.length, start, end);
sort(start, end, array);
}
private static void sort(int start, int end, short[] array) {
short temp;
int length = end - start;
if (length < 7) {
for (int i = start + 1; i < end; i++) {
for (int j = i; j > start && array[j - 1] > array[j]; j--) {
temp = array[j];
array[j] = array[j - 1];
array[j - 1] = temp;
}
}
return;
}
int middle = (start + end) / 2;
if (length > 7) {
int bottom = start;
int top = end - 1;
if (length > 40) {
length /= 8;
bottom = med3(array, bottom, bottom + length, bottom
+ (2 * length));
middle = med3(array, middle - length, middle, middle + length);
top = med3(array, top - (2 * length), top - length, top);
}
middle = med3(array, bottom, middle, top);
}
short partionValue = array[middle];
int a, b, c, d;
a = b = start;
c = d = end - 1;
while (true) {
while (b <= c && array[b] <= partionValue) {
if (array[b] == partionValue) {
temp = array[a];
array[a++] = array[b];
array[b] = temp;
}
b++;
}
while (c >= b && array[c] >= partionValue) {
if (array[c] == partionValue) {
temp = array[c];
array[c] = array[d];
array[d--] = temp;
}
c--;
}
if (b > c) {
break;
}
temp = array[b];
array[b++] = array[c];
array[c--] = temp;
}
length = a - start < b - a ? a - start : b - a;
int l = start;
int h = b - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
length = d - c < end - 1 - d ? d - c : end - 1 - d;
l = b;
h = end - length;
while (length-- > 0) {
temp = array[l];
array[l++] = array[h];
array[h++] = temp;
}
if ((length = b - a) > 0) {
sort(start, start + length, array);
}
if ((length = d - c) > 0) {
sort(end - length, end, array);
}
}
}