finding duplicate elements in java array

/**
 * @author lautturi.com 
 * Java example: java find out duplicate elements in array
 */

import java.util.Set;
import java.util.HashSet;

public class Lautturi {

	public static void main(String[] args) {
		int[] numArray = {3, 16, 17, 6, 3, 19, 21, 19};
		
		Set<Integer> set = new HashSet<>();
		for (int num : numArray) 
		{
		     if (set.add(num) == false) 
		     {
		        System.out.println("Found duplicate element "+num);
		     }
		} 
	}

}

output:

Found duplicate element 3
Found duplicate element 19