SortData.java

package com.ge.current.points;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.TreeMap;
import java.util.TreeSet;

public class SortData {
	public static void main(String[] args) {

		Comparator<Integer> comparator = new Comparator<Integer>() {
			@Override
			public int compare(Integer o1, Integer o2) {
				return o1 - o2;
			}
		};

		// Create a list of integers
		ArrayList<Integer> coll_int = new ArrayList<Integer>();
		coll_int.add(5);
		coll_int.add(3);
		coll_int.add(1);
		coll_int.add(6);
		coll_int.add(7);

		// Ascending
		Collections.sort(coll_int, (i1, i2) -> (i1 - i2));
		System.out.println("ASC: " + coll_int);
		// Descending
		Collections.sort(coll_int, (i1, i2) -> (i2 - i1));
		System.out.println("DESC: "+ coll_int);
		
		// Create a list of strings
		ArrayList<String> coll_string = new ArrayList<String>();
		coll_string.add("Sample");
		coll_string.add("Friends");
		coll_string.add("Dear");
		coll_string.add("Is");
		coll_string.add("Superb");

		// Ascending
		Collections.sort(coll_string, (s1, s2) -> s1.compareTo(s2));
		System.out.println("ASC: " + coll_string);
		// Descending
		Collections.sort(coll_string, (s1, s2) -> s2.compareTo(s1));
		System.out.println("DESC: "+ coll_string);

		TreeSet<Integer> treeset = new TreeSet<>(comparator);
		TreeMap<Integer, String> treemap = new TreeMap<>(comparator);
	}
}