Arrays.sort() can be used to sort arrays in Java in ascending / descending order.
Arrays.sort( array ); – This method is used to sort an array in ascending order.
Arrays.sort( array, Collections.reverseOrder() ); – To sort an array in descending order.
Primitives cannot be sorted in reverse using this method. So if you want to sort int, convert it into an Integer first and then sort.
Example 1: Sort a numeric array
import java.util.Arrays;
import java.util.Collections;
class CollectionTest
{
public static void main ( String[] args )
{
int[] array = { 7, 3, 1, 2, 5 } ;
Arrays.sort( array );
System.out.println( Arrays.toString( array ) );
Integer[] array2 = Arrays.stream( array ).boxed().toArray( Integer[]::new );
Arrays.sort( array2, Collections.reverseOrder() );
System.out.println( Arrays.toString( array2 ) );
}
}
Output:
[1, 2, 3, 5, 7]
[7, 5, 3, 2, 1]
Example 2: Sort an alphanumeric array
import java.util.Arrays;
import java.util.Collections;
class CollectionTest
{
public static void main ( String[] args )
{
String[] array = { “Mercury”, “Venus”, “Earth”, “Mars”, “Jupiter”, “Saturn” } ;
Arrays.sort( array );
System.out.println( Arrays.toString( array ) );
Arrays.sort( array, Collections.reverseOrder() );
System.out.println( Arrays.toString( array ) );
}
}
Output:
[Earth, Jupiter, Mars, Mercury, Saturn, Venus]
[Venus, Saturn, Mercury, Mars, Jupiter, Earth]