java.util

Class Arrays

java.lang.Object

java.util.Arrays

public class Arrays
extends Object

This class contains various methods for manipulating arrays (such as sorting and searching). This class also contains a static factory that allows arrays to be viewed as lists.

The methods in this class all throw a NullPointerException, if the specified array reference is null, except where noted.

The documentation for the methods contained in this class includes briefs description of the implementations. Such descriptions should be regarded as implementation notes, rather than parts of the specification. Implementors should feel free to substitute other algorithms, so long as the specification itself is adhered to.

This class is a member of the Java Collections Framework.

Since:

1.2, CLDC1.8

Method Summary

Methods

Modifier and Type	Method and Description
static <T> List<T>	asList(T... a) Returns a fixed-size list backed by the specified array.
static int	binarySearch(byte[] a, byte key) Searches the specified array of bytes for the specified value using the binary search algorithm.
static int	binarySearch(byte[] a, int fromIndex, int toIndex, byte key) Searches a range of the specified array of bytes for the specified value using the binary search algorithm.
static int	binarySearch(char[] a, char key) Searches the specified array of chars for the specified value using the binary search algorithm.
static int	binarySearch(char[] a, int fromIndex, int toIndex, char key) Searches a range of the specified array of chars for the specified value using the binary search algorithm.
static int	binarySearch(double[] a, double key) Searches the specified array of doubles for the specified value using the binary search algorithm.
static int	binarySearch(double[] a, int fromIndex, int toIndex, double key) Searches a range of the specified array of doubles for the specified value using the binary search algorithm.
static int	binarySearch(float[] a, float key) Searches the specified array of floats for the specified value using the binary search algorithm.
static int	binarySearch(float[] a, int fromIndex, int toIndex, float key) Searches a range of the specified array of floats for the specified value using the binary search algorithm.
static int	binarySearch(int[] a, int key) Searches the specified array of ints for the specified value using the binary search algorithm.
static int	binarySearch(int[] a, int fromIndex, int toIndex, int key) Searches a range of the specified array of ints for the specified value using the binary search algorithm.
static int	binarySearch(long[] a, int fromIndex, int toIndex, long key) Searches a range of the specified array of longs for the specified value using the binary search algorithm.
static int	binarySearch(long[] a, long key) Searches the specified array of longs for the specified value using the binary search algorithm.
static int	binarySearch(Object[] a, int fromIndex, int toIndex, Object key) Searches a range of the specified array for the specified object using the binary search algorithm.
static int	binarySearch(Object[] a, Object key) Searches the specified array for the specified object using the binary search algorithm.
static int	binarySearch(short[] a, int fromIndex, int toIndex, short key) Searches a range of the specified array of shorts for the specified value using the binary search algorithm.
static int	binarySearch(short[] a, short key) Searches the specified array of shorts for the specified value using the binary search algorithm.
static <T> int	binarySearch(T[] a, int fromIndex, int toIndex, T key, Comparator<? super T> c) Searches a range of the specified array for the specified object using the binary search algorithm.
static <T> int	binarySearch(T[] a, T key, Comparator<? super T> c) Searches the specified array for the specified object using the binary search algorithm.
static boolean[]	copyOf(boolean[] original, int newLength) Copies the specified array, truncating or padding with false (if necessary) so the copy has the specified length.
static byte[]	copyOf(byte[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static char[]	copyOf(char[] original, int newLength) Copies the specified array, truncating or padding with null characters (if necessary) so the copy has the specified length.
static double[]	copyOf(double[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static float[]	copyOf(float[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static int[]	copyOf(int[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static long[]	copyOf(long[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static short[]	copyOf(short[] original, int newLength) Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length.
static <T> T[]	copyOf(T[] original, int newLength) Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length.
static <T,U> T[]	copyOf(U[] original, int newLength, Class<? extends T[]> newType) Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length.
static boolean	equals(boolean[] a, boolean[] a2) Returns true if the two specified arrays of booleans are equal to one another.
static boolean	equals(byte[] a, byte[] a2) Returns true if the two specified arrays of bytes are equal to one another.
static boolean	equals(char[] a, char[] a2) Returns true if the two specified arrays of chars are equal to one another.
static boolean	equals(double[] a, double[] a2) Returns true if the two specified arrays of doubles are equal to one another.
static boolean	equals(float[] a, float[] a2) Returns true if the two specified arrays of floats are equal to one another.
static boolean	equals(int[] a, int[] a2) Returns true if the two specified arrays of ints are equal to one another.
static boolean	equals(long[] a, long[] a2) Returns true if the two specified arrays of longs are equal to one another.
static boolean	equals(Object[] a, Object[] a2) Returns true if the two specified arrays of Objects are equal to one another.
static boolean	equals(short[] a, short[] a2) Returns true if the two specified arrays of shorts are equal to one another.
static void	fill(boolean[] a, boolean val) Assigns the specified boolean value to each element of the specified array of booleans.
static void	fill(byte[] a, byte val) Assigns the specified byte value to each element of the specified array of bytes.
static void	fill(char[] a, char val) Assigns the specified char value to each element of the specified array of chars.
static void	fill(double[] a, double val) Assigns the specified double value to each element of the specified array of doubles.
static void	fill(float[] a, float val) Assigns the specified float value to each element of the specified array of floats.
static void	fill(int[] a, int val) Assigns the specified int value to each element of the specified array of ints.
static void	fill(long[] a, long val) Assigns the specified long value to each element of the specified array of longs.
static void	fill(Object[] a, Object val) Assigns the specified Object reference to each element of the specified array of Objects.
static void	fill(short[] a, short val) Assigns the specified short value to each element of the specified array of shorts.
static void	sort(byte[] a) Sorts the specified array into ascending numerical order.
static void	sort(byte[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(char[] a) Sorts the specified array into ascending numerical order.
static void	sort(char[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(double[] a) Sorts the specified array into ascending numerical order.
static void	sort(double[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(float[] a) Sorts the specified array into ascending numerical order.
static void	sort(float[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(int[] a) Sorts the specified array into ascending numerical order.
static void	sort(int[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(long[] a) Sorts the specified array into ascending numerical order.
static void	sort(long[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static void	sort(Object[] a) Sorts the specified array of objects into ascending order, according to the natural ordering of its elements.
static void	sort(Object[] a, int fromIndex, int toIndex) Sorts the specified range of the specified array of objects into ascending order, according to the natural ordering of its elements.
static void	sort(short[] a) Sorts the specified array into ascending numerical order.
static void	sort(short[] a, int fromIndex, int toIndex) Sorts the specified range of the array into ascending order.
static <T> void	sort(T[] a, Comparator<? super T> c) Sorts the specified array of objects according to the order induced by the specified comparator.
static <T> void	sort(T[] a, int fromIndex, int toIndex, Comparator<? super T> c) Sorts the specified range of the specified array of objects according to the order induced by the specified comparator.

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

asList

public static <T> List<T> asList(T... a)

Returns a fixed-size list backed by the specified array. (Changes to the returned list "write through" to the array.) This method acts as bridge between array-based and collection-based APIs, in combination with Collection.toArray(). The returned list implements RandomAccess.

This method also provides a convenient way to create a fixed-size list initialized to contain several elements:

     List<String> stooges = Arrays.asList("Larry", "Moe", "Curly");
 

Type Parameters:

T - the class of the objects in the array

Parameters:

a - the array by which the list will be backed

Returns:

a list view of the specified array

binarySearch

public static int binarySearch(byte[] a,
               byte key)

Searches the specified array of bytes for the specified value using the binary search algorithm. The array must be sorted (as by the sort(byte[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(byte[] a,
               int fromIndex,
               int toIndex,
               byte key)

Searches a range of the specified array of bytes for the specified value using the binary search algorithm. The range must be sorted (as by the sort(byte[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(char[] a,
               char key)

Searches the specified array of chars for the specified value using the binary search algorithm. The array must be sorted (as by the sort(char[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(char[] a,
               int fromIndex,
               int toIndex,
               char key)

Searches a range of the specified array of chars for the specified value using the binary search algorithm. The range must be sorted (as by the sort(char[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(double[] a,
               double key)

Searches the specified array of doubles for the specified value using the binary search algorithm. The array must be sorted (as by the sort(double[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(double[] a,
               int fromIndex,
               int toIndex,
               double key)

Searches a range of the specified array of doubles for the specified value using the binary search algorithm. The range must be sorted (as by the sort(double[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(float[] a,
               float key)

Searches the specified array of floats for the specified value using the binary search algorithm. The array must be sorted (as by the sort(float[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(float[] a,
               int fromIndex,
               int toIndex,
               float key)

Searches a range of the specified array of floats for the specified value using the binary search algorithm. The range must be sorted (as by the sort(float[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found. This method considers all NaN values to be equivalent and equal.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(int[] a,
               int key)

Searches the specified array of ints for the specified value using the binary search algorithm. The array must be sorted (as by the sort(int[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(int[] a,
               int fromIndex,
               int toIndex,
               int key)

Searches a range of the specified array of ints for the specified value using the binary search algorithm. The range must be sorted (as by the sort(int[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(long[] a,
               int fromIndex,
               int toIndex,
               long key)

Searches a range of the specified array of longs for the specified value using the binary search algorithm. The range must be sorted (as by the sort(long[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(long[] a,
               long key)

Searches the specified array of longs for the specified value using the binary search algorithm. The array must be sorted (as by the sort(long[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static int binarySearch(Object[] a,
               int fromIndex,
               int toIndex,
               Object key)

Searches a range of the specified array for the specified object using the binary search algorithm. The range must be sorted into ascending order according to the natural ordering of its elements (as by the sort(Object[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. (If the range contains elements that are not mutually comparable (for example, strings and integers), it cannot be sorted according to the natural ordering of its elements, hence results are undefined.) If the range contains multiple elements equal to the specified object, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

ClassCastException - if the search key is not comparable to the elements of the array within the specified range.

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(Object[] a,
               Object key)

Searches the specified array for the specified object using the binary search algorithm. The array must be sorted into ascending order according to the natural ordering of its elements (as by the sort(Object[]) method) prior to making this call. If it is not sorted, the results are undefined. (If the array contains elements that are not mutually comparable (for example, strings and integers), it cannot be sorted according to the natural ordering of its elements, hence results are undefined.) If the array contains multiple elements equal to the specified object, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

ClassCastException - if the search key is not comparable to the elements of the array.

binarySearch

public static int binarySearch(short[] a,
               int fromIndex,
               int toIndex,
               short key)

Searches a range of the specified array of shorts for the specified value using the binary search algorithm. The range must be sorted (as by the sort(short[], int, int) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static int binarySearch(short[] a,
               short key)

Searches the specified array of shorts for the specified value using the binary search algorithm. The array must be sorted (as by the sort(short[]) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements with the specified value, there is no guarantee which one will be found.

Parameters:

a - the array to be searched

key - the value to be searched for

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

binarySearch

public static <T> int binarySearch(T[] a,
                   int fromIndex,
                   int toIndex,
                   T key,
                   Comparator<? super T> c)

Searches a range of the specified array for the specified object using the binary search algorithm. The range must be sorted into ascending order according to the specified comparator (as by the sort(T[], int, int, Comparator) method) prior to making this call. If it is not sorted, the results are undefined. If the range contains multiple elements equal to the specified object, there is no guarantee which one will be found.

Type Parameters:

T - the class of the objects in the array

Parameters:

a - the array to be searched

fromIndex - the index of the first element (inclusive) to be searched

toIndex - the index of the last element (exclusive) to be searched

key - the value to be searched for

c - the comparator by which the array is ordered. A null value indicates that the elements' natural ordering should be used.

Returns:

index of the search key, if it is contained in the array within the specified range; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element in the range greater than the key, or toIndex if all elements in the range are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

ClassCastException - if the range contains elements that are not mutually comparable using the specified comparator, or the search key is not comparable to the elements in the range using this comparator.

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

Since:

1.6

binarySearch

public static <T> int binarySearch(T[] a,
                   T key,
                   Comparator<? super T> c)

Searches the specified array for the specified object using the binary search algorithm. The array must be sorted into ascending order according to the specified comparator (as by the sort(T[], Comparator) method) prior to making this call. If it is not sorted, the results are undefined. If the array contains multiple elements equal to the specified object, there is no guarantee which one will be found.

Type Parameters:

T - the class of the objects in the array

Parameters:

a - the array to be searched

key - the value to be searched for

c - the comparator by which the array is ordered. A null value indicates that the elements' natural ordering should be used.

Returns:

index of the search key, if it is contained in the array; otherwise, (-(insertion point) - 1). The insertion point is defined as the point at which the key would be inserted into the array: the index of the first element greater than the key, or a.length if all elements in the array are less than the specified key. Note that this guarantees that the return value will be >= 0 if and only if the key is found.

Throws:

ClassCastException - if the array contains elements that are not mutually comparable using the specified comparator, or the search key is not comparable to the elements of the array using this comparator.

copyOf

public static boolean[] copyOf(boolean[] original,
               int newLength)

Copies the specified array, truncating or padding with false (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain false. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with false elements to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static byte[] copyOf(byte[] original,
            int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain (byte)0. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static char[] copyOf(char[] original,
            int newLength)

Copies the specified array, truncating or padding with null characters (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain '\\u000'. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with null characters to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static double[] copyOf(double[] original,
              int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0d. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static float[] copyOf(float[] original,
             int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0f. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static int[] copyOf(int[] original,
           int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static long[] copyOf(long[] original,
            int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain 0L. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static short[] copyOf(short[] original,
             int newLength)

Copies the specified array, truncating or padding with zeros (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain (short)0. Such indices will exist if and only if the specified length is greater than that of the original array.

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with zeros to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static <T> T[] copyOf(T[] original,
             int newLength)

Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain null. Such indices will exist if and only if the specified length is greater than that of the original array. The resulting array is of exactly the same class as the original array.

Type Parameters:

T - the class of the objects in the array

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

Returns:

a copy of the original array, truncated or padded with nulls to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

Since:

1.6

copyOf

public static <T,U> T[] copyOf(U[] original,
               int newLength,
               Class<? extends T[]> newType)

Copies the specified array, truncating or padding with nulls (if necessary) so the copy has the specified length. For all indices that are valid in both the original array and the copy, the two arrays will contain identical values. For any indices that are valid in the copy but not the original, the copy will contain null. Such indices will exist if and only if the specified length is greater than that of the original array. The resulting array is of the class newType.

Type Parameters:

U - the class of the objects in the original array

T - the class of the objects in the returned array

Parameters:

original - the array to be copied

newLength - the length of the copy to be returned

newType - the class of the copy to be returned

Returns:

a copy of the original array, truncated or padded with nulls to obtain the specified length

Throws:

NegativeArraySizeException - if newLength is negative

NullPointerException - if original is null

ArrayStoreException - if an element copied from original is not of a runtime type that can be stored in an array of class newType

Since:

1.6

equals

public static boolean equals(boolean[] a,
             boolean[] a2)

Returns true if the two specified arrays of booleans are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(byte[] a,
             byte[] a2)

Returns true if the two specified arrays of bytes are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(char[] a,
             char[] a2)

Returns true if the two specified arrays of chars are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(double[] a,
             double[] a2)

Returns true if the two specified arrays of doubles are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Two doubles d1 and d2 are considered equal if:

    new Double(d1).equals(new Double(d2))

(Unlike the == operator, this method considers NaN equals to itself, and 0.0d unequal to -0.0d.)

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

See Also:

Double.equals(Object)

equals

public static boolean equals(float[] a,
             float[] a2)

Returns true if the two specified arrays of floats are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Two floats f1 and f2 are considered equal if:

    new Float(f1).equals(new Float(f2))

(Unlike the == operator, this method considers NaN equals to itself, and 0.0f unequal to -0.0f.)

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

See Also:

Float.equals(Object)

equals

public static boolean equals(int[] a,
             int[] a2)

Returns true if the two specified arrays of ints are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(long[] a,
             long[] a2)

Returns true if the two specified arrays of longs are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(Object[] a,
             Object[] a2)

Returns true if the two specified arrays of Objects are equal to one another. The two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. Two objects e1 and e2 are considered equal if (e1==null ? e2==null : e1.equals(e2)). In other words, the two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

equals

public static boolean equals(short[] a,
             short[] a2)

Returns true if the two specified arrays of shorts are equal to one another. Two arrays are considered equal if both arrays contain the same number of elements, and all corresponding pairs of elements in the two arrays are equal. In other words, two arrays are equal if they contain the same elements in the same order. Also, two array references are considered equal if both are null.

Parameters:

a - one array to be tested for equality

a2 - the other array to be tested for equality

Returns:

true if the two arrays are equal

fill

public static void fill(boolean[] a,
        boolean val)

Assigns the specified boolean value to each element of the specified array of booleans.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(byte[] a,
        byte val)

Assigns the specified byte value to each element of the specified array of bytes.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(char[] a,
        char val)

Assigns the specified char value to each element of the specified array of chars.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(double[] a,
        double val)

Assigns the specified double value to each element of the specified array of doubles.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(float[] a,
        float val)

Assigns the specified float value to each element of the specified array of floats.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(int[] a,
        int val)

Assigns the specified int value to each element of the specified array of ints.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(long[] a,
        long val)

Assigns the specified long value to each element of the specified array of longs.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

fill

public static void fill(Object[] a,
        Object val)

Assigns the specified Object reference to each element of the specified array of Objects.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

Throws:

ArrayStoreException - if the specified value is not of a runtime type that can be stored in the specified array

fill

public static void fill(short[] a,
        short val)

Assigns the specified short value to each element of the specified array of shorts.

Parameters:

a - the array to be filled

val - the value to be stored in all elements of the array

sort

public static void sort(byte[] a)

Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(byte[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(char[] a)

Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(char[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(double[] a)

Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo(java.lang.Double): -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(double[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all double values: -0.0d == 0.0d is true and a Double.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Double.compareTo(java.lang.Double): -0.0d is treated as less than value 0.0d and Double.NaN is considered greater than any other value and all Double.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(float[] a)

Sorts the specified array into ascending numerical order.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo(java.lang.Float): -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(float[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

The < relation does not provide a total order on all float values: -0.0f == 0.0f is true and a Float.NaN value compares neither less than, greater than, nor equal to any value, even itself. This method uses the total order imposed by the method Float.compareTo(java.lang.Float): -0.0f is treated as less than value 0.0f and Float.NaN is considered greater than any other value and all Float.NaN values are considered equal.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(int[] a)

Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(int[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(long[] a)

Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(long[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static void sort(Object[] a)

Sorts the specified array of objects into ascending order, according to the natural ordering of its elements. All elements in the array must implement the Comparable interface. Furthermore, all elements in the array must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Parameters:

a - the array to be sorted

Throws:

ClassCastException - if the array contains elements that are not mutually comparable (for example, strings and integers)

IllegalArgumentException - (optional) if the natural ordering of the array elements is found to violate the Comparable contract

sort

public static void sort(Object[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the specified array of objects into ascending order, according to the natural ordering of its elements. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in this range must implement the Comparable interface. Furthermore, all elements in this range must be mutually comparable (that is, e1.compareTo(e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element (inclusive) to be sorted

toIndex - the index of the last element (exclusive) to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex or (optional) if the natural ordering of the array elements is found to violate the Comparable contract

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

ClassCastException - if the array contains elements that are not mutually comparable (for example, strings and integers).

sort

public static void sort(short[] a)

Sorts the specified array into ascending numerical order.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

sort

public static void sort(short[] a,
        int fromIndex,
        int toIndex)

Sorts the specified range of the array into ascending order. The range to be sorted extends from the index fromIndex, inclusive, to the index toIndex, exclusive. If fromIndex == toIndex, the range to be sorted is empty.

Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.

Parameters:

a - the array to be sorted

fromIndex - the index of the first element, inclusive, to be sorted

toIndex - the index of the last element, exclusive, to be sorted

Throws:

IllegalArgumentException - if fromIndex > toIndex

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length

sort

public static <T> void sort(T[] a,
            Comparator<? super T> c)

Sorts the specified array of objects according to the order induced by the specified comparator. All elements in the array must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the array).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Type Parameters:

T - the class of the objects to be sorted

Parameters:

a - the array to be sorted

c - the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.

Throws:

ClassCastException - if the array contains elements that are not mutually comparable using the specified comparator

IllegalArgumentException - (optional) if the comparator is found to violate the Comparator contract

sort

public static <T> void sort(T[] a,
            int fromIndex,
            int toIndex,
            Comparator<? super T> c)

Sorts the specified range of the specified array of objects according to the order induced by the specified comparator. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.) All elements in the range must be mutually comparable by the specified comparator (that is, c.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the range).

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.

Type Parameters:

T - the class of the objects to be sorted

Parameters:

a - the array to be sorted

fromIndex - the index of the first element (inclusive) to be sorted

toIndex - the index of the last element (exclusive) to be sorted

c - the comparator to determine the order of the array. A null value indicates that the elements' natural ordering should be used.

Throws:

ClassCastException - if the array contains elements that are not mutually comparable using the specified comparator.

IllegalArgumentException - if fromIndex > toIndex or (optional) if the comparator is found to violate the Comparator contract

ArrayIndexOutOfBoundsException - if fromIndex < 0 or toIndex > a.length