I need help with getting started for this in Java. Codes listed below.

Complete the CircularArrayQueue.java class implementation of the Queue.java interface so that it does not use a count field. This implementation must have only the following fields:

DEFAULT_CAPACITY

front

rear

queue

Implement the methods

enter

leave

front

isEmpty

isFull

expandCapacity

Write a test class to test each of the methods you implement.

Queue.java

public interface Queue { /** * The element enters the queue at the rear. */ public void enter(E element);

/** * The front element leaves the queue and is returned. * @throws java.util.NoSuchElementException if queue is empty. */ public E leave();

/** * Returns True if the queue is empty. */ public boolean isEmpty();

/** * Returns the front element without removing it. * @throws java.util.NoSuchElementException if queue is empty. */ public E front(); }

CircularArrayQueue.java

import java.util.NoSuchElementException; import java.util.StringJoiner;

/** * A queue implemented using a circular buffer. * * @author (your name) * @version (a version number or a date) */ public class CircularArrayQueue implements Queue { public static final int DEFAULT_CAPACITY = 100; private int front; // Index of the front cell of the queue private int rear; // Index of the next available cell of the queue private E[] queue; // Circular buffer

public CircularArrayQueue(int initialCapacity) { queue = (E[]) new Object[initialCapacity]; front = 0; rear = 0; }

public CircularArrayQueue() { this(DEFAULT_CAPACITY); } @Override public void enter(E element) { // Implement as part of assignment }

@Override public E leave() throws NoSuchElementException { // Implement as part of assignment }

@Override public E front() throws NoSuchElementException { // Implement as part of assignment } @Override public boolean isEmpty() { // Implement as part of assignment } private boolean isFull() { // Implement as part of assignment }

private int incrementIndex(int index) { return (index + 1) % queue.length; } private void expandCapacity() { // Implement as part of assignment } @Override public String toString() { StringJoiner result = new StringJoiner("[", ", ", "]"); for (int i = front; i != rear; i = incrementIndex(i)) { result.add(queue[i].toString()); } return result.toString(); } }