example of HashSet in java

/**
 * @author lautturi.com
 * Java example: example of HashSet in java
 */

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		Set<Integer> set = new HashSet<>();
		set.add(1);
		set.add(2);
		set.add(3);
		
        System.out.println("HashSet: " + set);
		 
	}
}

output:

HashSet: [1, 2, 3]