hashset add 28e e 29 method in java

1import java.util.HashSet;
2public class HashSetAddMethodExample
3{
4   public static void main(String[] args)
5   {
6      HashSet<String> hs = new HashSet<String>();
7      // populating hash set
8      hs.add("violet");
9      hs.add("indigo");
10      hs.add("blue");
11      hs.add("green");
12      hs.add("yellow");
13      System.out.println("HashSet of colors: " + hs);
14   }
15}