import java.util.*;

/**
 * The class Sales maintains a list of the orders.
 *
 * @author  張維
 * @version  1.0.0
 * @see  Order
 * @see  Vector
 */
 public class Sales  {
  	
	   /* A vector that contains references to <code>Order</code> objects. */
     private Vector orders;
     	  	
	   /**
	    * Creates the vector orders, which is initially empty.
	    */
	   public Sales( ) {
	    	
	    	orders = new Vector( );
	   }
	    	 
	   /**
	    * Adds the specified order to the vector orders. 
	    *
	    * @param order  the <code>Order</code> object.
	    */
	   public void addOrder(Order order) {
	   	
	  	  orders.add(order);
	   }
	   	  
	   /**
	   	* Returns an iterator over the instances in the vector orders. 
	   	*
	   	* @return  an <code>Iterator</code> object.
	   	*/
	   public Iterator getOrdersIterator( ) {
	   		
	   		return orders.iterator( );
	   }
	   	
	   	
	   /**
	   	* Returns the number of instances in the vector orders.
	   	*
	   	* @return the number of <code>Order</code> objects in this orders.
	   	*/
	   public int getNumberOfOrders( ) {
	   		
	   	  return orders.size( );
	   	}
   }