/**
 * An object that notifies LinerObserver objects about
 * lines of text
 *
 * @author  Prof. David Bernstein, James Madison University
 * @version 3.0
 */
public interface LineSubject
{
    /**
     * Add an observer
     *
     * @param observer   The LineObserver to add
     */
    public void addObserver(LineObserver observer);


    /**
     * Get the last line
     *
     * @return   The line
     */
    public String getLine();



    /**
     * Notify observers of a line
     */
    public void notifyObservers();


    /**
     * Remove an observer
     *
     * @param observer   The LineObserver to remove
     */
    public void removeObserver(LineObserver observer);
}