code: @SuppressWarnings("unchecked")
  	public E get (int index) {
  		return index >= size ? null : (E)queue[index];
  	}
docs: Retrieves the element at the specified index. If such an element doesn't exist {@code null} is returned.
  <p>
  Iterating the queue by index is <em>not</em> guaranteed to traverse the elements in any particular order.
  
  @return the element at the specified index in this queue.