java.util.Arrays sort(int[] a)


On this document we will be showing a java example on how to use the sort(int[] a) method of Arrays Class. Basically the sort(int[] a) method sorts the specified array into ascending numerical order. The sort() method is overloaded in such a way that each primitive data type is handled. On this example we will be showing the sorting of array of int.


  • 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.
  • This method will yield the same result as sort(int[] a, int fromIndex, int toIndex) method on such cases that the fromIndex is 0 and endIndex is equal to length. In short Arrays.sort(int[] a) is equals to Arrays.sort(int[] a, 0,a.length).

Method Syntax

public static void sort(int[] a)

Method Argument

Data Type Parameter Description
int[] a the array to be sorted

Method Returns

The sort(int[] a) method returns void.


Requires Java 1.2 and up

Java Arrays sort(int[] a) Example

Below is a java code demonstrates the use of sort(int[] a) method of Arrays class. The example presented might be simple however it shows the behaviour of the sort(int[] a) method.


import java.util.Arrays;

 * A java example source code to demonstrate
 * the use of sort(int[] a) method of Arrays class

public class ArraysSortIntExample {

	public static void main(String[] args) {

		// initialize a new String array
		int[] a = new int[]{-4,4,12,1,0,-5,4,2};
		// print the contents of array of int
		// sort our array of int in ascending order
		// print the sorted array of int


The above java example source code demonstrates the use of sort(int[] a) method of Arrays class. We simply declare a new int array and we printed the values using the toString() method of Arrays class. Then we sorted the int array using the sort() method and the sorted values were also printed the same way as what we did on the original/unsorted array.

Sample Output

Below is the sample output when you run the above example.

Arrays sort(int[] a) example output