HashSet Class

HashSet

·         Creates a collection that makes use of a hash table for storage.

·         A hash table is a data structure that stores information by mapping the key of each data element into an array position or index.

·         HashSet extends AbstractSet and implements the Set interface.

Example:

import java.util.HashSet;

import java.util.Set;

public class HashSetDemo
{

   public static void main(String[] args)
   {

      Set objSet = new HashSet();

      objSet.add("Harry");

      objSet.add("Emaini");

      objSet.add("Voldmort");

      objSet.add("Snape");

      objSet.add("Dumbuldore");

      System.out.println("Contents of the set :");

      System.out.println(objSet);

      System.out.println("Size of the set : " + objSet.size());

      System.out.println("\nContents of the set after adding 2 elements :");

      objSet.add("Tom Riddle");

      objSet.add("slytherin");

      System.out.println(objSet);

      System.out.println("Size of the set : " + objSet.size());

   }

}