Java and Set (Interface)

package com.java.myapp;

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

public class MyClass {

	public static void main(String[] args) {
	   
		Set<Integer> mySet = new HashSet<Integer>();
		mySet.add(100);
		mySet.add(200);
		mySet.add(300);
		mySet.add(400);
		mySet.add(100);
		
        System.out.println("Value = " + mySet);
        System.out.println("Size = " + mySet.size());
        
        System.out.println("================");
        
        for(int val : mySet){
        	System.out.println(val);
         }
		
	}
	
}