In this post , we will see how to implement Queue using Linked List in java. Queue is abstract data type which demonstrates First in first out (FIFO) behaviour. We will implement same behaviour using Array.
Although java provides implementation for all abstract data types such as Stack , Queue and LinkedList but it is always good idea to understand basic data structures and implement them yourself.
Please note that LinkedList implementation of Queue is dynamic in nature.
There are two most important operations of Queue: enqueue : It is operation when we insert element into the queue. dequeue : It is operation when we remove element from the queue. Read more at
Java Program to implement Queue using Linked List:
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packageorg.arpit.java2blog;
publicclassQueueUsingLinkedListMain
{
privateNode front,rear;
privateintcurrentSize;// number of items
//class to define linked node
privateclassNode
{
intdata;
Node next;
}
//Zero argument constructor
publicQueueUsingLinkedListMain()
{
front=null;
rear=null;
currentSize=0;
}
publicbooleanisEmpty()
{
return(currentSize==0);
}
//Remove item from the beginning of the list.
publicintdequeue()
{
intdata=front.data;
front=front.next;
if(isEmpty())
{
rear=null;
}
currentSize--;
System.out.println(data+" removed from the queue");
