/**
 * 
 */
package dataStructures1112;

import dataStructures1112.EmptyQueueException;
import dataStructures1112.InvertibleQueue;
import dataStructures1112.QueueInList;

/**
 * @author rm.cruz
 * 
 */
public class InvertibleQueueInList<E> extends QueueInList<E> implements
		InvertibleQueue<E> {

	private static final long serialVersionUID = 1L;

	private boolean isInverted;

	public InvertibleQueueInList() {
		super();
		isInverted = false;

	}

	@Override
	public void enqueue(E element) {
		if (isInverted)
			list.addFirst(element);
		else
			list.addLast(element);
		
	}

	@Override
	public E dequeue() throws EmptyQueueException {
		if (isInverted)
			return list.removeLast();
		else
			return list.removeFirst();
	}

	@Override
	public void invert() {
		isInverted = !isInverted;

	}

}