import java.util.LinkedList;
public class LinkedListQueue {
    // Declaring Linked List, Node Head & Tail
    LinkedList<String> list;
    Node head;
    Node tail;
    class Node {
        int data;
        Node prev;
        Node next;
        /**
         * Node Constructor
         *
         * @param data
         */
        Node(int d) {
            data = d;
        }
    }
    /**
     * Linked List Queue Parameterized Constructor
     */
    public LinkedListQueue() {
        list = new LinkedList<String>();
    }
    /**
     * Enqueue Method (adds element to tail)
     *
     * @param string
     */
    public void enqueue(String string) {
        list.add(string);
    }
    /**
     * Dequeue Method (removes first element)
     */
    public void dequeue() {
        if (list.isEmpty()) {   /* check if linked list is empty */
            System.out.println("The Queue is Empty.");
        } else {
            list.removeFirst();    /* remove first element of linked list */
        }
    }
    /**
     * Size Method (Size of queue)
     *
     * @return size
     */
    public int size() {
        return list.size();
    }
    /**
     * Display Method (prints element in queue)
     */
    public void display() {
        for (int i = 0; i < list.size(); i++) {
            System.out.print(list.get(i) + "  ");
        }
        System.out.println("\n");
    }
    /**
     * getHead Method (gets head of the queue)
     *
     * @return first element
     */
    public String getHead() {
        if (list.isEmpty()) {
            return "The Queue is Empty.";
        } else {
            return list.getFirst();
        }
    }
    /**
     * getTail Method (gets tail of the queue)
     *
     * @return last element
     */
    public String getTail() {
        if (list.isEmpty()) {
            return "The Queue is Empty.";
        } else {
            return list.getLast();
        }
    }
    /**
     * IsEmpty Method (checks if queue is empty)
     *
     * @return true/false
     */
    public boolean isEmpty() {
        if (list.isEmpty()) {     /* checks if linked list is empty */
            return true;
        } else {
            return false;
        }
    }
    /**
     * Delete Queue Method (clears queue)
     */
    public void deleteQueue() {
        list.clear();
    }
}

import java.util.LinkedList;
public class Driver {
    public static void main(String[] args) {
        // New instance of linked list queue
        LinkedListQueue llq = new LinkedListQueue();
        // Checking if stack is empty
        System.out.println("Is the Queue empty? " + llq.isEmpty());
        llq.enqueue("Queue Element 1");
        llq.enqueue("Queue Element 2");
        llq.enqueue("Queue Element 3");
        llq.enqueue("Queue Element 4");
        llq.enqueue("Queue Element 5");
        System.out.println("The element at the head is: " + llq.getHead());
        System.out.println("The element at the tail is: " + llq.getTail());
        // Checking size of stack
        System.out.println("Size of the Queue: " + llq.size());
        // Printing Stack
        System.out.println("*****Display the Queue*****");
        llq.display();
        llq.enqueue("Queue Element 6");
        llq.dequeue();
        llq.dequeue();
        // Printing Stack
        System.out.println("*****Display the Queue*****");
        llq.display();
        llq.dequeue();
        llq.dequeue();
        // Checking if stack is empty
        System.out.println("Is the stack empty? " + llq.isEmpty());
        // Clearing Stack
        llq.deleteQueue();
        // Checking if stack is empty
        System.out.println("Is the stack empty? " + llq.isEmpty());
    }
}

LinkedListQueue llq = new LinkedListQueue();