Deque.java

/* TEAM BOATY
 * Maxwell Vale, Dan Gelfand, Tim Marder
 * APCS02 pd02
 * lab#02 -- All Hands on Deque!
 * 2018-04-20
*/
 
// Interface for a Deque --> A Double Ended Queue
 

public interface Deque<Card> {

  // Inserts the specified element at the front of this deque
  // unless it would violate capacity restrictions.
  public boolean offerFirst(Card e);

  // Inserts the specified element at the end of this deque
  // unless it would violate capacity restrictions.
  public boolean offerLast(Card e);

  // Retrieves and removes the first element of this deque
  // Returns the head of the deque or null if empty
  public Card pollFirst();

  // Retrieves and removes the last element of the deque
  // Returns the tail of the deque or null if empty
  public Card pollLast();

  // Retrieves, but does not remove, the first element of the deque
  // Returns the head of the deque or null if empty
  public Card peekFirst();

  // Retrieves, but does not remove, the last element of the deque
  // Returns the tail of the deque or null if empty
  public Card peekLast();

  // Checks if the deque is empty
  // Returns true if empty and false otherwise
  public boolean isEmpty();

} // end interface Deque