package class6_2_LinearObserver_start;

/**
 * Classes implementing this interface
 * will "observe" the position of the subject.
 * They will automatically be notified when the observer is available.
 */
public interface PositionObserver {
    /**
     * This method will automatically be called each second.
     * (A more general solution would include the time-stamp.)
     * @param positionMeters the current position, in meters
     */
    void update(double positionMeters);
}