Import java.util.ArrayList; /** Interface for a Queue data structure *  * * @param  data type */ public interface QueueInterface {   /** provide three constructors    * 1. takes an int as the size of the queue    * 2. default constructor - uses a default as the size of the queue    * 3. takes an ArrayList as a parameter, and fills the Queue with the    *     elements of the ArrayList, First element in the ArrayList is the first element in the Queue    *    *       YOU MUST MAKE A COPY OF LIST AND ADD THOSE ELEMENTS TO THE QUEUE, if you use the    *       list reference within your Queue, you will be allowing direct access to the data of    *       your Queue causing a possible security breach.    */    /**    * Determines if Queue is empty    * @return true if Queue is empty, false if not    */   public boolean isEmpty();    /**    * Determines of the Queue is empty    * @return    */   public boolean isFull();      /**    * Deletes and returns the element at the front of the Queue    * @return the element at the front of the Queue    */   public T dequeue() throws QueueUnderflowException;    /**    * Number of elements in the Queue    * @return the number of elements in the Queue    */   public int size();      /**    * Adds an element to the end of the Queue    * @param e the element to add to the end of the Queue    * @return true if the add was successful, false if not    */   public boolean enqueue(T e) throws QueueOverflowException;         /**    * Returns the string representation of the elements in the Queue,     * the beginning of the string is the front of the queue    * @return string representation of the Queue with elements    */   public String toString();      /**    * Returns the string representation of the elements in the Queue, the beginning of the string is the front of the queue    * Place the delimiter between all elements of the Queue    * @return string representation of the Queue with elements separated with the delimiter    */   public String toString(String delimiter); }