/**
 * The cpsc331Stack interface repressents the Stack ADT as described
 * in CPSC 331.
 *
 * @author Mike Jacobson
 * @version 1.0
 */
public interface cpsc331Stack<T> {
  
  /**
   * Tests whether the stack is empty.
   *
   * @return true if the stack is empty, false otherwise
   */
  public boolean isEmpty();
  
  /**
   * Pushes the object x onto the top of the stack.
   *
   * @param x object to be pushed onto the stack.
   */
  public void push(T x);
  
  /**
   * Returns the object at the top of the stack.
   *
   * @return reference to the item at the top of the stack
   * @throws EmptyStackException if the stack is empty
   */
  public T top();
  
  /**
  * Removes and returns the object at the top of the stack.
  *
  * @return reference to the item at the top of the stack
  * @throws EmptyStackException if the stack is empty
  */
  public T pop();
}