Using Classes and Objects - Java Software Solutions: Foundations of Program Design - page 134

LISTING 3.4 continued

{
final double TAX_RATE = 0.06; // 6% sales tax

int quantity;
double subtotal, tax, totalCost, unitPrice;

Scanner scan = new Scanner (System.in);

NumberFormat fmt1 = NumberFormat.getCurrencyInstance();
NumberFormat fmt2 = NumberFormat.getPercentInstance();

System.out.print ("Enter the quantity: ");
quantity = scan.nextInt();

System.out.print ("Enter the unit price: ");
unitPrice = scan.nextDouble();

subtotal = quantity * unitPrice;
tax = subtotal * TAX_RATE;
totalCost = subtotal + tax;

// Print output with appropriate formatting
System.out.println ("Subtotal: " + fmt1.format(subtotal));
System.out.println ("Tax: " + fmt1.format(tax) + " at "
+ fmt2.format(TAX_RATE));
System.out.println ("Total: " + fmt1.format(totalCost));
}
}

OUTPUT

Enter the quantity: 5
Enter the unit price: 3.87
Subtotal: $19.35
Tax: $1.16 at 6%
Total: $20.51

The DecimalFormat Class
Unlike the NumberFormat class, the DecimalFormat class is instantiated in
the traditional way using the new operator. Its constructor takes a string that
represents the pattern that will guide the formatting process. We can then use the