Various Operations on Queue Using Linked List in Java

In computer programming, queues are a basic data structure used to organise collections of elements in a specific order. The java.util.Queue interface and the java.util.LinkedList class are just two of the built-in classes and interfaces provided by Java for working with queues. In this article, we'll examine the numerous operations that a Java linked list can carry out on a queue

Creating a Queue Using a Linked List in Java

By creating a LinkedList object in Java and then using polymorphism to treat it as a Queue object, we can build a queue using a linked list. Here's an illustration:

As an alternative, we can simply create a queue using the java.util.Queue interface:

Adding Elements to a Queue Using a Linked List

Using a linked list, we can use the add() or offer() technique to add an element to the end of a queue. When the queue is full, the add() method throws an exception, but the offer() method returns a boolean value showing whether the element was added successfully. As an illustration, consider the following Using a linked list:

Removing Elements from a Queue Using a Linked List

We can use the remove() or poll() technique to remove an element from the front of the queue. While the poll() method returns null if the queue is empty, the remove() method raises an exception if it is. As an illustration, consider the following:

Retrieving the Element at the Front of the Queue Using a Linked List

Using a linked list, the element() or peek() technique can be used to obtain the element at the front of the queue without removing it. While the peek() method returns null if the queue is empty, the element() method raises an exception if the queue is empty. Here's an illustration:

Iterating over a Queue Using a Linked List

A for-each loop or an iterator can be used to run over a queue created from a linked list. Here's an illustration:

Complete Code

QueueExample.java

Output:

Queue after adding elements: [element 1, element 2] Queue after removing elements: [] Front element of the queue: null Iterating over the queue: 

Because the queue is empty after all the components have been removed, take note that the output for the queue's front element is null.

Conclusion

In this piece, we looked at the different Java operations that can be done on a queue by using a linked list. These actions include building a list, filling it with elements, removing elements from it, retrieving the element at the front of the queue, and iterating over a queue. It is simple to build and use queues in your programmes thanks to the built-in classes and interfaces offered by Java.