Program to sort Integer array by using Arrays.sort (we will define Comparator to sort elements in descending order)

import java.util.Arrays;
import java.util.Comparator;
class SortDescending implements Comparator<Integer> {
   @Override
   public int compare(Integer o1, Integer o2) {
          //using Comparator to sort array in descending order.
          return o2.compareTo(o1);
   }
}

/**
* @author AnkitMittal
* Copyright (c), AnkitMittal JavaMadeSoEasy.com
* Main class
*/
public class ArraysSort {
   public static void main(String...a){
       Integer intArray[]={2,3,1};
      
       System.out.print("Array before sorting : ");
       for(int i: intArray){
          System.out.print(i+" ");
       }
       Arrays.sort(intArray, new SortDescending());
      
       System.out.print("\nArray after sorting in descending order : ");
       for(int i: intArray){
          System.out.print(i+" ");
       }
      
   }
}
/*OUTPUT
Array before sorting : 2 3 1
Array after sorting in descending order : 3 2 1
*/

eEdit
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