java.util.Arrays

The Arrays class is primarily used in array manipulation such as sorting and searching. There are static methods available too on this class that allows conversion of Arrays to List.  It must be noted that all methods of Arrays class is throwing NullPointerException so watch out for this so proper handling should be in place in dealing with Arrays methods.

Arrays Class Syntax

public class Arrays extends Object

Java Arrays Compatibility

The Arrays class has been around since Java 1.2 though some of it’s methods were added on the later releases.

Arrays Method Usage Examples

The following are the detailed list of StringBuilder methods and descriptions. We have also provided links to examples of each method on the list.

Modifier and Type Method and Description
static  List 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​(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​(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​(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 int compare​(boolean[] a, boolean[] b)
Compares two boolean arrays lexicographically.
static int compare​(boolean[] a, int aFromIndex, int aToIndex, boolean[] b, int bFromIndex, int bToIndex)
Compares two boolean arrays lexicographically over the specified ranges.
static int compare​(byte[] a, byte[] b)
Compares two byte arrays lexicographically.
static int compare​(byte[] a, int aFromIndex, int aToIndex, byte[] b, int bFromIndex, int bToIndex)
Compares two byte arrays lexicographically over the specified ranges.
static int compare​(char[] a, char[] b)
Compares two char arrays lexicographically.
static int compare​(char[] a, int aFromIndex, int aToIndex, char[] b, int bFromIndex, int bToIndex)
Compares two char arrays lexicographically over the specified ranges.
static int compare​(double[] a, double[] b)
Compares two double arrays lexicographically.
static int compare​(double[] a, int aFromIndex, int aToIndex, double[] b, int bFromIndex, int bToIndex)
Compares two double arrays lexicographically over the specified ranges.
static int compare​(float[] a, float[] b)
Compares two float arrays lexicographically.
static int compare​(float[] a, int aFromIndex, int aToIndex, float[] b, int bFromIndex, int bToIndex)
Compares two float arrays lexicographically over the specified ranges.
static int compare​(int[] a, int[] b)
Compares two int arrays lexicographically.
static int compare​(int[] a, int aFromIndex, int aToIndex, int[] b, int bFromIndex, int bToIndex)
Compares two int arrays lexicographically over the specified ranges.
static int compare​(long[] a, int aFromIndex, int aToIndex, long[] b, int bFromIndex, int bToIndex)
Compares two long arrays lexicographically over the specified ranges.
static int compare​(long[] a, long[] b)
Compares two long arrays lexicographically.
static int compare​(short[] a, int aFromIndex, int aToIndex, short[] b, int bFromIndex, int bToIndex)
Compares two short arrays lexicographically over the specified ranges.
static int compare​(short[] a, short[] b)
Compares two short arrays lexicographically.
static > compare​(T[] a, int aFromIndex, int aToIndex, T[] b, int bFromIndex, int bToIndex)
Compares two Object arrays lexicographically over the specified ranges.
int
static  int compare​(T[] a, int aFromIndex, int aToIndex, T[] b, int bFromIndex, int bToIndex, Comparator<? super T> cmp)
Compares two Object arrays lexicographically over the specified ranges.
static > compare​(T[] a, T[] b)
Compares two Object arrays, within comparable elements, lexicographically.
int
static  int compare​(T[] a, T[] b, Comparator<? super T> cmp)
Compares two Object arrays lexicographically using a specified comparator.
static int compareUnsigned​(byte[] a, byte[] b)
Compares two byte arrays lexicographically, numerically treating elements as unsigned.
static int compareUnsigned​(byte[] a, int aFromIndex, int aToIndex, byte[] b, int bFromIndex, int bToIndex)
Compares two byte arrays lexicographically over the specified ranges, numerically treating elements as unsigned.
static int compareUnsigned​(int[] a, int[] b)
Compares two int arrays lexicographically, numerically treating elements as unsigned.
static int compareUnsigned​(int[] a, int aFromIndex, int aToIndex, int[] b, int bFromIndex, int bToIndex)
Compares two int arrays lexicographically over the specified ranges, numerically treating elements as unsigned.
static int compareUnsigned​(long[] a, int aFromIndex, int aToIndex, long[] b, int bFromIndex, int bToIndex)
Compares two long arrays lexicographically over the specified ranges, numerically treating elements as unsigned.
static int compareUnsigned​(long[] a, long[] b)
Compares two long arrays lexicographically, numerically treating elements as unsigned.
static int compareUnsigned​(short[] a, int aFromIndex, int aToIndex, short[] b, int bFromIndex, int bToIndex)
Compares two short arrays lexicographically over the specified ranges, numerically treating elements as unsigned.
static int compareUnsigned​(short[] a, short[] b)
Compares two short arrays lexicographically, numerically treating elements as unsigned.
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,​U> 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.
T[]
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,​U> copyOfRange​(U[] original, int from, int to, Class<? extends T[]> newType)
Copies the specified range of the specified array into a new array.
T[]
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​(boolean[] a, int aFromIndex, int aToIndex, boolean[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of booleans, over the specified ranges, 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​(byte[] a, int aFromIndex, int aToIndex, byte[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of bytes, over the specified ranges, 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​(char[] a, int aFromIndex, int aToIndex, char[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of chars, over the specified ranges, 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​(double[] a, int aFromIndex, int aToIndex, double[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of doubles, over the specified ranges, 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​(float[] a, int aFromIndex, int aToIndex, float[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of floats, over the specified ranges, 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​(int[] a, int aFromIndex, int aToIndex, int[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of ints, over the specified ranges, are equal to one another.
static boolean equals​(long[] a, int aFromIndex, int aToIndex, long[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of longs, over the specified ranges, 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, int aFromIndex, int aToIndex, short[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of shorts, over the specified ranges, 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 boolean equals​(Object[] a, int aFromIndex, int aToIndex, Object[] b, int bFromIndex, int bToIndex)
Returns true if the two specified arrays of Objects, over the specified ranges, 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​(T[] a, int aFromIndex, int aToIndex, T[] b, int bFromIndex, int bToIndex, Comparator<? super T> cmp)
Returns true if the two specified arrays of Objects, over the specified ranges, are equal to one another.
static  boolean equals​(T[] a, T[] a2, Comparator<? super T> cmp)
Returns true if the two specified arrays of Objects 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​(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 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.