Java Program. Use the information in the given code below to perform the followi

Question

Java Program. Use the information in the given code below to perform the following:

Assume myQueue is an object of the class ArrayQueue.

You may call any of the public methods of ArrayQueue.

You may also declare additional queue objects.  

Make a copy of myQueue, leaving myQueue unchanged.

You only need to write a segment that makes a copy of myQueue and leaves myQueue unchanged.

Use the code below for reference.

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

//public

interface QueueInterface

{

public void enqueue(Object item);

// Effect: Adds item to the rear of this queue.

// Precondition: This queue is not full.

// Postcondition: item is at the rear of this queue.

public Object dequeue();

// Effect: Removes front element from this queue and returns it.

// Precondition: This queue is not empty.

// Postconditions: Front element has been removed from this queue.

// Return value = (the removed element)

public boolean isEmpty();

// Effect: Determines whether this queue is empty.

// Postcondition: Return value = (this queue is empty)

public boolean isFull();

// Effect: Determines whether this queue is full.

// Postcondition: Return value = (queue is full)

}

//----------------------------------------------------------------------------

// ArrayQueue.java by Dale/Joyce/Weems Chapter 4

//

// Implements QueueInterface using an array to hold the queue items

//----------------------------------------------------------------------------

//package ch04.queues;

//public

class ArrayQueue1 implements QueueInterface

{

private Object[] queue; // Array that holds queue elements

private int capacity; // size of the array (capacity of the queue)

private int numItems = 0; // number of items on the queue

// private int front = -1; // index of front of queue

// private int rear = 0; // index of rear of queue

// Constructors

public ArrayQueue1()

{

queue = new Object[100];

capacity = 100;

}

public ArrayQueue1(int maxSize)

{

queue = new Object[maxSize];

capacity = maxSize;

}

public void enqueue(Object item)

// Adds an element to the front of this queue

{

if(!isFull())

{ queue[numItems] = item;

numItems = numItems + 1;

}

}

public Object dequeue()

// Removes an element from the rear of this queue

{

Object toReturn = null;

if(!isEmpty())

{

toReturn = queue[0];

for(int i = 0; i <= numItems - 2; i++)

queue[i] = queue[i + 1];

queue[numItems - 1] = null;

numItems = numItems - 1;

}

return toReturn;

}

public boolean isEmpty()

// Checks if this queue is empty

{

return (numItems == 0);

}

public boolean isFull()

// Checks if this queue is full

{

return (numItems == capacity);

}

}

Explanation / Answer

Please find the code below to create a copy of myQueue called "copy_myQueue"

ArrayQueue1 myQueue = new ArrayQueue1();
ArrayQueue1 copy_myQueue = new ArrayQueue1();

while(!myQueue.isEmpty()) {
Object item = myQueue.dequeue();
copy_myQueue.enqueue(item);
myQueue.enqueue(item);
}

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