Arrays.sort is not working in java for descending order code example

Example: sorting array in descending order java

// A sample Java program to sort a subarray 
// in descending order using Arrays.sort(). 
import java.util.Arrays; 
import java.util.Collections; 
  
public class SortExample 
{ 
    public static void main(String[] args) 
    { 
        // Note that we have Integer here instead of 
        // int[] as Collections.reverseOrder doesn't 
        // work for primitive types. 
        Integer[] arr = {13, 7, 6, 45, 21, 9, 2, 100}; 
  
        // Sorts arr[] in descending order 
        Arrays.sort(arr, Collections.reverseOrder()); 
  
        System.out.printf("Modified arr[] : %s", 
                          Arrays.toString(arr)); 
    } 
}