    01: /**
    02:    A simple invoice formatter.
    03: */
    04: public class SimpleFormatter implements InvoiceFormatter
    05: {
    06:    public String formatHeader()
    07:    {
    08:       total = 0;
    09:       return "     I N V O I C E\n\n\n";
    10:    }
    11:
    12:    public String formatLineItem(LineItem item)
    13:    {
    14:       total += item.getPrice();
    15:       return item.toString() + ": $"
    16:          + item.getPrice() + "\n";
    17:    }
    18:
    19:    public String formatFooter()
    20:    {
    21:       return "\n\nTOTAL DUE: $" + total + "\n";
    22:    }
    23:
    24:    private double total;
    25: }
    26: