LinkedList

LinkedList is available since Java 1.2

LinkedList extends AbstractSequentialList class.

Linked implements following Interfaces:

• Serializable
• Cloneable
• Iterable<E>
• Collection<E>
• Deque<E>
• List<E> 
• Queue<E> 

The underlying data structure used is Doubly linked list.

LinkedList has two constructors:

• LinkedList()
• LinkedList(Collection c)             

Characteristics:

• LinkedList allows null element.
• LinkedList maintains insertion order of elements.
• LinkedList is non-synchronized.
• In LinkedList insertion and deletion operation are faster because there is not need of shift operation after insertion and deletion of element in List.
• LinkedList class can be used to make list, stack and queue data structure.

Example:

import java.util.*; 
public class LinkedListFlight{ 
 public static void main(String args[]){ 
 
  LinkedList<String> linkedList = new LinkedList<String>(); 
  linkedList.add("A"); 
  linkedList.add("B"); 
  linkedList.add("C"); 
  linkedList.add("D"); 
  linkedList.add(null);     
  System.out.println(linkedList);      
 } 
} 

Output
[A, B, C, D, null]