Class Arrays
java.util
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. (For example, the algorithm used by sort(Object[]) does not have to be a mergesort, but it does have to be stable.)

This class is a member of the Java Collections Framework.

Since:
1.2
Version:
1.71, 04/21/06
Author:
Josh Bloch, Neal Gafter, John Rose

Method Summary
static 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(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(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(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 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 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[]
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[]
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[]
copyOfRange(boolean[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static byte[]
copyOfRange(byte[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static char[]
copyOfRange(char[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static double[]
copyOfRange(double[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static float[]
copyOfRange(float[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static int[]
copyOfRange(int[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static long[]
copyOfRange(long[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static short[]
copyOfRange(short[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static T[]
copyOfRange(T[] original, int from, int to)
Copies the specified range of the specified array into a new array.
static T[]
copyOfRange(U[] original, int from, int to, Class<? extends T> newType)
Copies the specified range of the specified array into a new array.
static boolean
deepEquals(Object[] a1, Object[] a2)
Returns true if the two specified arrays are deeply equal to one another.
static int
deepHashCode(Object[] a)
Returns a hash code based on the "deep contents" of the specified array.
static String
deepToString(Object[] a)
Returns a string representation of the "deep contents" of the specified array.
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(Object[] a, Object[] a2)
Returns true if the two specified arrays of Objects 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(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(boolean[] a, int fromIndex, int toIndex, boolean val)
Assigns the specified boolean value to each element of the specified range 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(byte[] a, int fromIndex, int toIndex, byte val)
Assigns the specified byte value to each element of the specified range 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(char[] a, int fromIndex, int toIndex, char val)
Assigns the specified char value to each element of the specified range 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(double[] a, int fromIndex, int toIndex, double val)
Assigns the specified double value to each element of the specified range 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(float[] a, int fromIndex, int toIndex, float val)
Assigns the specified float value to each element of the specified range 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(int[] a, int fromIndex, int toIndex, int val)
Assigns the specified int value to each element of the specified range of the specified array of ints.
static void
fill(Object[] a, int fromIndex, int toIndex, Object val)
Assigns the specified Object reference to each element of the specified range of the specified array of Objects.
static void
fill(Object[] a, Object val)
Assigns the specified Object reference to each element of the specified array of Objects.
static void
fill(long[] a, int fromIndex, int toIndex, long val)
Assigns the specified long value to each element of the specified range of the specified array of longs.
static void
fill(long[] a, long val)
Assigns the specified long value to each element of the specified array of longs.
static void
fill(short[] a, int fromIndex, int toIndex, short val)
Assigns the specified short value to each element of the specified range of the specified array of shorts.
static void
fill(short[] a, short val)
Assigns the specified short value to each element of the specified array of shorts.
static int
hashCode(boolean[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(byte[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(char[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(double[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(float[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(int[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(Object[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(long[] a)
Returns a hash code based on the contents of the specified array.
static int
hashCode(short[] a)
Returns a hash code based on the contents of the specified array.
static void
sort(byte[] a)
Sorts the specified array of bytes into ascending numerical order.
static void
sort(byte[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of bytes into ascending numerical order.
static void
sort(char[] a)
Sorts the specified array of chars into ascending numerical order.
static void
sort(char[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of chars into ascending numerical order.
static void
sort(double[] a)
Sorts the specified array of doubles into ascending numerical order.
static void
sort(double[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of doubles into ascending numerical order.
static void
sort(float[] a)
Sorts the specified array of floats into ascending numerical order.
static void
sort(float[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of floats into ascending numerical order.
static void
sort(int[] a)
Sorts the specified array of ints into ascending numerical order.
static void
sort(int[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of ints into ascending numerical 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(long[] a)
Sorts the specified array of longs into ascending numerical order.
static void
sort(long[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of longs into ascending numerical order.
static void
sort(short[] a)
Sorts the specified array of shorts into ascending numerical order.
static void
sort(short[] a, int fromIndex, int toIndex)
Sorts the specified range of the specified array of shorts into ascending numerical order.
static 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.
static void
sort(T[] a, Comparator<? super T> c)
Sorts the specified array of objects according to the order induced by the specified comparator.
static String
toString(boolean[] a)
Returns a string representation of the contents of the specified array.
static String
toString(byte[] a)
Returns a string representation of the contents of the specified array.
static String
toString(char[] a)
Returns a string representation of the contents of the specified array.
static String
toString(double[] a)
Returns a string representation of the contents of the specified array.
static String
toString(float[] a)
Returns a string representation of the contents of the specified array.
static String
toString(int[] a)
Returns a string representation of the contents of the specified array.
static String
toString(Object[] a)
Returns a string representation of the contents of the specified array.
static String
toString(long[] a)
Returns a string representation of the contents of the specified array.
static String
toString(short[] a)
Returns a string representation of the contents of the specified array.
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Method Detail
sort
public static void sort(long[] a)
Sorts the specified array of longs into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.
Parameters:
a - the array to be sorted

sort
public static void sort(long[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of longs into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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 of ints into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.
Parameters:
a - the array to be sorted

sort
public static void sort(int[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of ints into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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(short[] a)
Sorts the specified array of shorts into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.
Parameters:
a - the array to be sorted

sort
public static void sort(short[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of shorts into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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 of chars into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.
Parameters:
a - the array to be sorted

sort
public static void sort(char[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of chars into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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(byte[] a)
Sorts the specified array of bytes into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.
Parameters:
a - the array to be sorted

sort
public static void sort(byte[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of bytes into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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 of doubles into ascending numerical order.

The < relation does not provide a total order on all floating-point values; although they are distinct numbers -0.0 == 0.0 is true and a NaN value compares neither less than, greater than, nor equal to any floating-point value, even itself. To allow the sort to proceed, instead of using the < relation to determine ascending numerical order, this method uses the total order imposed by Double.compareTo(). This ordering differs from the < relation in that -0.0 is treated as less than 0.0 and NaN is considered greater than any other floating-point value. For the purposes of sorting, all NaN values are considered equivalent and equal.

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

Parameters:
a - the array to be sorted

sort
public static void sort(double[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of doubles into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The < relation does not provide a total order on all floating-point values; although they are distinct numbers -0.0 == 0.0 is true and a NaN value compares neither less than, greater than, nor equal to any floating-point value, even itself. To allow the sort to proceed, instead of using the < relation to determine ascending numerical order, this method uses the total order imposed by Double.compareTo(). This ordering differs from the < relation in that -0.0 is treated as less than 0.0 and NaN is considered greater than any other floating-point value. For the purposes of sorting, all NaN values are considered equivalent and equal.

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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 of floats into ascending numerical order.

The < relation does not provide a total order on all floating-point values; although they are distinct numbers -0.0f == 0.0f is true and a NaN value compares neither less than, greater than, nor equal to any floating-point value, even itself. To allow the sort to proceed, instead of using the < relation to determine ascending numerical order, this method uses the total order imposed by Float.compareTo(). This ordering differs from the < relation in that -0.0f is treated as less than 0.0f and NaN is considered greater than any other floating-point value. For the purposes of sorting, all NaN values are considered equivalent and equal.

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

Parameters:
a - the array to be sorted

sort
public static void sort(float[] a,
                        int fromIndex,
                        int toIndex)
Sorts the specified range of the specified array of floats into ascending numerical order. The range to be sorted extends from index fromIndex, inclusive, to index toIndex, exclusive. (If fromIndex==toIndex, the range to be sorted is empty.)

The < relation does not provide a total order on all floating-point values; although they are distinct numbers -0.0f == 0.0f is true and a NaN value compares neither less than, greater than, nor equal to any floating-point value, even itself. To allow the sort to proceed, instead of using the < relation to determine ascending numerical order, this method uses the total order imposed by Float.compareTo(). This ordering differs from the < relation in that -0.0f is treated as less than 0.0f and NaN is considered greater than any other floating-point value. For the purposes of sorting, all NaN values are considered equivalent and equal.

The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

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.

The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance.

Parameters:
a - the array to be sorted
Throws:
ClassCastException - if the array contains elements that are not mutually comparable (for example, strings and integers).

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.

The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance.

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

sort
public static 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.

The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance.

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.

sort
public static 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.

The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance.

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

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(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(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(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 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(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(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(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(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(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