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By Doug Lowe

The Arrays class (package: java.util) provides a collection of static methods that are useful for working with arrays. Because the Arrays class provides only static methods, it has no constructors.

Method Description
static int binarySearch(array,
key)
Searches for the specified key value in an array. The return
value is the index of the element that matches the key. The method
returns -1 if the key can’t be
found. The array and the key must be of the same type and can be
any primitive type or an object.
static array copyOf(arrayOriginal,
newLength)
Returns an array that’s a copy of arrayOriginal. The newLength parameter need not equal the original
array’s length. If newLength is larger,
the method pads the new array with zeros. If newLength is smaller, the method doesn’t copy
all of the original array’s values.
static array copyOfRange(arrayOriginal,
from, to)
Does what the copyOf method does, but
copies only a selected slice of values (from one index to another)
of the original array.
boolean deepEquals(array1,
array2)
Returns true if the two arrays have
the same element values. This method works for arrays of two or
more dimensions.
boolean equals(array1, array2) Returns true if the two arrays have
the same element values. This method checks equality only for
one-dimensional arrays.
static void fill(array, value) Fills the array with the specified value. The value and array
must be of the same type and can be any primitive type or an
object.
static void fill(array, from, to,
value)
Fills the elements indicated by the from and to
int
parameters with the specified value. The value and array
must be of the same type and can be any primitive type or an
object.
static void sort(array) Sorts the array in ascending sequence.
static void sort(array, from,
to)
Sorts the specified elements of the array in ascending
sequence.
static String toString(array) Formats the array values in a string. Each element value is
enclosed in brackets, and the element values are separated with
commas.