/**
 * The requirements of a currency converter
 *
 * @author  Prof. David Bernstein, James Madison University
 * @version 1.0
 */
public interface CurrencyConverter
{

    /**
     * Convert between currencies
     *
     * @param amount  The amount of "from" currency to convert
     * @param from    The "from" currency
     * @param to      The "to" currency
     * @return        The equivalent amount of "to" currency (or -1)
     */
    public double convert(double amount, String from, String to);

}