/** * Indicate that there was no passenger at a pickup point. *  * @author David J. Barnes and Michael Kolling * @version 2006.03.30 */public class MissingPassengerException extends RuntimeException{    private Vehicle vehicle;    /**     * Constructor for objects of class MissingPassengerException.     * @param vehicle The vehicle expecting a passenger.     */    public MissingPassengerException(Vehicle vehicle)    {        super("Missing passenger at pickup location.");    }    /**     * @return The vehicle for which there was no passenger.     */    public Vehicle getVehicle()    {        return vehicle;    }}