Java -LinkedHashSet class

• LinkedHashSet contains unique elements only like HashSet. It extends HashSet class and implements Set interface.
• LinkedHashSet maintains the insertion order. Elements gets sorted in the same sequence in which they have been added to the Set.

 

class LinkedHashSet <T>

We can create LinkedHashSet for storing String type elements as follows:

LinkedHashSet <String> hs=new LinkedHashSet <String> ();

We can create LinkedHashSet for storing Integer type elements as follows:

LinkedHashSet <Integer> hs=new LinkedHashSet <Integer> ();

Example of LinkedHashSet:

1. import java.util.*;
2. class LinkedHashSetDemo
   {
3.  public static void main(String args[]){
5.   LinkedHashSet<String> lhs=new LinkedHashSet<String>();
6.   lhs.add(“A”);
7.   lhs.add(“B”);
8.   lhs.add(“A”);
9.   lhs.add(“C”);
11.   Iterator<String> itr=lhs.iterator();
12.   while(itr.hasNext()){
13.    System.out.println(itr.next());
14.   }
15.  }
16. }

Output:
       A
       B
       C

Another Example of LinkedHashSet:

import java.util.LinkedHashSet;
public class LinkedHashSetDemo1 {
     public static void main(String args[]) {
         // LinkedHashSet of String Type
         LinkedHashSet<String> lhs = new LinkedHashSet<String>();

         // Adding elements to the LinkedHashSet of type <String>
         lhs.add("A");
         lhs.add("B");
         lhs.add("C");
         lhs.add("D");
         lhs.add("E");
         lhs.add("F");
         System.out.println(lhs);

         // LinkedHashSet declaration of Integer Type
         LinkedHashSet<Integer> lhs2 = new LinkedHashSet<Integer>();

         // Adding elements to the LinkedHashSet of type<Integer>
         lhs2.add(10);
         lhs2.add(20);
         lhs2.add(30);
         lhs2.add(40);
         lhs2.add(50);
         lhs2.add(60);
         System.out.println(lhs2);
    }
}

Output:

[A, B, C, D, E, F]
[10, 20, 30, 40, 50, 60]

declaration