001 package users.events;
002
003 /**
004 * An abstract adapter class for receiving user data events. The methods in this class are
005 * empty. This class exists as convenience for creating listener objects.
006 *
007 * <p>Extend this class to create a UserDataEvent listener and override the methods for the
008 * events of interest. (If you implement the UserDataListener interface, you have to define
009 * all of the methods in it. This abstract class defines empty method bodies for them all, so you
010 * can concentrate on defining methods only for events you care about.)</p>
011 *
012 * <p>Create a listener object using the extended class and then register it with a
013 * {@link users.UserManager} using the UserManager's {@link users.UserManager#addUserDataListener} method.
014 * When a user is added or removed, the relevant method in the listener object is invoked, and the
015 * {@link UserDataEvent} is passed to it.</p>
016 *
017 * @see UserDataEvent
018 * @see UserDataListener
019 * @see users.UserManager
020 *
021 * @author Steffen Zschaler
022 * @version 2.0 06/05/1999
023 * @since v2.0
024 */
025 public abstract class UserDataAdapter implements UserDataListener {
026
027 /**
028 * Called whenever a user was added to the source. The new user will be contained
029 * in the event object.
030 *
031 * @param e the event object describing the event.
032 *
033 * @override Sometimes
034 */
035 public void userAdded(UserDataEvent e) {}
036
037 /**
038 * Called whenever a user was deleted from the source. The deleted user will be
039 * contained in the event object.
040 *
041 * @param e the event object describing the event.
042 *
043 * @override Sometimes
044 */
045 public void userDeleted(UserDataEvent e) {}
046 }