/*Note: the "public" is omitted, but should appear, in which case each of
  these would go into a separate .java file.
*/

interface SaleItem {
    public double getPrice();
    public void purchase();
    public boolean purchased();
}

interface ShippedItem {
    public static final int MAX_DISTANCE = 100; //can't ship farther than this
    public double getDistance();
    public boolean shipped();
}