HashSet in Java

HashSet in Collection Framework

HashSet is Implementer class of Set Interface. HashSet supports hashing mechanism to store the value that means all the elements are stored in un-shorted random order (the elements will not be in same order as inserted).

Points to Remember

• HashSet are not allows to store duplicate elements.
• HashSet allows to store heterogeneous elements.
• For retrieving elements from HashSet you can use foreach loop and iterator interface to retrieve the elements.
• HashSet is not Synchronized means multiple threads can work Sanctimoniously.
• HashSet allows to store null value.

import java.util.*;

class HashSetDemo
{
public static void main(String args[])
	{
	HashSet<String> hs=new HashSet<String>();
	hs.add("Java");
	hs.add("C-lang");
	hs.add("C++");
	hs.add("Java");
   System.out.println(hs);
   Iterator i=hs.iterator();
   System.out.println("Forward Direction");

	while(l.hasNext())
	{
	System.out.println(i.next());
	}
	}
}

Java
C-lang
C++