Getting reverse order comparator : Comparator Interface « Collections « Java Tutorial

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
public class MainClass {
  public static void main(String args[]) throws Exception {
    Comparator comp = Collections.reverseOrder();
    String[] a = new String[] { "A", "C", "B" };
    Arrays.sort(a, comp);
    for (int i = 0, n = a.length; i < n; i++) {

9.40.Comparator Interface
9.40.1.System-Defined Comparable Classes
9.40.2.Writing Your own Comparator
9.40.3.Getting reverse order comparator
9.40.4.Implementing a Comparator for a class
9.40.5.Use a custom comparator.
9.40.6.Sort an array of strings in reverse order.
9.40.7.Sort an array of strings, ignore case difference.
9.40.8.Use a comparator to sort accounts by last name.
9.40.9.Comparator uses a Collator to determine the proper, case-insensitive lexicographical ordering of two strings.
9.40.10.Calendar Comparator
9.40.11.Invertible Comparator