CashRegister.java.html

  1  /**
  2     A cash register totals up sales and computes change due.
  3  */
  4  public class CashRegister
  5  {
  6     private double purchase;
  7     private double payment;
  8  
  9     /**
 10        Constructs a cash register with no money in it.
 11     */
 12     public CashRegister()
 13     {
 14        purchase = 0;
 15        payment = 0;
 16     }
 17  
 18     /**
 19        Records the sale of an item.
 20        @param amount the price of the item
 21     */
 22     public void recordPurchase(double amount)
 23     {
 24        purchase = purchase + amount;
 25     }
 26  
 27     /**
 28        Processes a payment received from the customer.
 29        @param amount the amount of the payment
 30     */
 31     public void receivePayment(double amount)
 32     {
 33        payment = payment + amount;
 34     }
 35  
 36     /**
 37        Computes the change due and resets the machine for the next customer.
 38        @return the change due to the customer
 39     */
 40     public double giveChange()
 41     {   
 42        double change = payment - purchase;
 43        purchase = 0;
 44        payment = 0;
 45        return change;
 46     }
 47  }