/**                                              
   This class tests the CashRegister class.      
*/                                               
public class CashRegisterTester                  
{                                                
   public static void main(String[] args)        
   {                                             
      CashRegister register = new CashRegister();
                                                 
      register.recordPurchase(0.75);             
      register.recordPurchase(1.50);             
      register.enterPayment(2, 0, 5, 0, 0);      
      System.out.print("Change: ");              
      System.out.println(register.giveChange()); 
      System.out.println("Expected: 0.25");      
                                                 
      register.recordPurchase(2.25);             
      register.recordPurchase(19.25);            
      register.enterPayment(23, 2, 0, 0, 0);     
      System.out.print("Change: ");              
      System.out.println(register.giveChange()); 
      System.out.println("Expected: 2.0");       
   }                                             
}

Output:

Change: 0.25
Expected: 0.25
Change: 2.0
Expected: 2.0