Sort ArrayList in Descending order using Comparator with Java Collections

Java 8Object Oriented ProgrammingProgramming

In order to sort ArrayList in Descending order using Comparator, we need to use the Collections.reverseOrder() method which returns a comparator which gives the reverse of the natural ordering on a collection of objects that implement the Comparable interface.

Declaration − The java.util.Collections.reverseOrder() method is declared as follows -

public static <T>Comparator<T> reverseOrder()

Let us see a program to sort an ArrayList in Descending order using Comparator  with Java Collections −

Example

 Live Demo

import java.util.*;
public class Example {
   public static void main (String[] args) {
      ArrayList<Integer> list = new ArrayList<Integer>();
      list.add(10);
      list.add(50);
      list.add(30);
      list.add(20);
      list.add(40);
      list.add(60);
      System.out.println("Original list : " + list);
      Comparator c = Collections.reverseOrder();
      Collections.sort(list,c);
      System.out.println("Sorted list using Comparator : " + list);
   }
}

Output

Original list : [10, 50, 30, 20, 40, 60]
Sorted list using Comparator : [60, 50, 40, 30, 20, 10]
raja
Published on 09-Jan-2019 12:27:07
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