The reversed() method of Comparator Interface in Java returns a comparator that imposes the reverse ordering of this comparator. If you use sort method of the array and passes this comparator after applying the reversed method then it will sort the array in reverse order.
Syntax:
default Comparator<T> reversed()
Parameters: This method accepts nothing.
Return value: This method returns a comparator that imposes the reverse ordering of this comparator.
Below programs illustrate reversed() method:
Program 1:
Java
// Java program to demonstrate // Comparator.reversed() method import java.util.*; public class GFG { public static void main(String[] args) { String[] Arraystrings = { "aman" , "amar" , "avik" }; System.out.println( "before sort : " + Arrays.toString(Arraystrings)); Comparator<String> comp = (String::compareTo); Arrays.sort(Arraystrings, comp.reversed()); System.out.println( "after sort : " + Arrays.toString(Arraystrings)); } } |
before sort : [aman, amar, avik] after sort : [avik, amar, aman]
Program 2:
Java
// Java program to demonstrate // Comparator.reversed() method import java.util.*; public class GFG { public static void main(String[] args) { String[] list = { "KKR" , "CSK" , "MI" , "KXIP" , "RCB" , "SRH" , "DC" , "RR" }; System.out.println( "Before sorting:" ); System.out.println(Arrays.toString(list)); Comparator<String> comp = (String::compareTo); Arrays.sort(list, comp.reversed()); System.out.println( "After sorting:" ); System.out.println(Arrays.toString(list)); } } |
Before sorting: [KKR, CSK, MI, KXIP, RCB, SRH, DC, RR] After sorting: [SRH, RR, RCB, MI, KXIP, KKR, DC, CSK]
References: https://docs.oracle.com/javase/10/docs/api/java/util/Comparator.html#reversed()