import java.util.Enumeration;

public interface MyQueue {

    /**
     * Indicates the status of the queue.
     * @return <code>true</code> if the queue is empty.
     */
    public boolean isEmpty();

    /**
     * Attaches an item to the queue.
     * @param <code>item</code> the Object to be queued.
     */
    public void enqueue(Object item);

    /**
     * Detaches an item from the queue.
     * @return the item least recently queued.
     * @exception NoSuchElementException if the queue is empty.
     */
    public Object dequeue();

    /**
     * Enumerates the elements in the queue in the order
     * in which they would be dequeued.
     * @return the enumeration.
     * @exception NoSuchElementException if the <tt>nextElement</tt> method
     *            is called when there is no next element.
     */
    public Enumeration elements();

}