Notificação de Follow usando o twitter4j

public static void mains(String[] args) throws TwitterException {
        TwitterStream twitterStream = new TwitterStreamFactory().getInstance();
        twitterStream.addListener(listener);
}

 static UserStreamListener listener = new UserStreamListener() {
        public void onStatus(Status status) {
            System.out.println("onStatus @" + status.getUser().getScreenName() + " - " + status.getText());
        }
        public void onDeletionNotice(StatusDeletionNotice statusDeletionNotice) {
            System.out.println("Got a status deletion notice id:" + statusDeletionNotice.getStatusId());
        }
        public void onDeletionNotice(long directMessageId, long userId) {
            System.out.println("Got a direct message deletion notice id:" + directMessageId);
        }
        public void onTrackLimitationNotice(int numberOfLimitedStatuses) {
            System.out.println("Got a track limitation notice:" + numberOfLimitedStatuses);
        }
        public void onScrubGeo(long userId, long upToStatusId) {
            System.out.println("Got scrub_geo event userId:" + userId + " upToStatusId:" + upToStatusId);
        }
        public void onFriendList(long[] friendIds) {
            System.out.print("onFriendList");
            for (long friendId : friendIds) {
                System.out.print(" " + friendId);
            }
            System.out.println();
        }
        public void onFavorite(User source, User target, Status favoritedStatus) {
            System.out.println("onFavorite source:@"
                    + source.getScreenName() + " target:@"
                    + target.getScreenName() + " @"
                    + favoritedStatus.getUser().getScreenName() + " - "
                    + favoritedStatus.getText());
        }
        public void onUnfavorite(User source, User target, Status unfavoritedStatus) {
            System.out.println("onUnFavorite source:@"
                    + source.getScreenName() + " target:@"
                    + target.getScreenName() + " @"
                    + unfavoritedStatus.getUser().getScreenName()
                    + " - " + unfavoritedStatus.getText());
        }
        public void onFollow(User source, User followedUser) {
            System.out.println("onFollow source:@"
                    + source.getScreenName() + " target:@"
                    + followedUser.getScreenName());
        }
        public void onRetweet(User source, User target, Status retweetedStatus) {
            System.out.println("onRetweet @"
                    + retweetedStatus.getUser().getScreenName() + " - "
                    + retweetedStatus.getText());
        }
        public void onDirectMessage(DirectMessage directMessage) {
            System.out.println("onDirectMessage text:"
                    + directMessage.getText());
        }
        public void onUserListMemberAddition(User addedMember, User listOwner, UserList list) {
            System.out.println("onUserListMemberAddition added member:@"
                    + addedMember.getScreenName()
                    + " listOwner:@" + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListMemberDeletion(User deletedMember, User listOwner, UserList list) {
            System.out.println("onUserListMemberDeleted deleted member:@"
                    + deletedMember.getScreenName()
                    + " listOwner:@" + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListSubscription(User subscriber, User listOwner, UserList list) {
            System.out.println("onUserListSubscribed subscriber:@"
                    + subscriber.getScreenName()
                    + " listOwner:@" + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListUnsubscription(User subscriber, User listOwner, UserList list) {
            System.out.println("onUserListUnsubscribed subscriber:@"
                    + subscriber.getScreenName()
                    + " listOwner:@" + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListCreation(User listOwner, UserList list) {
            System.out.println("onUserListCreated listOwner:@"
                    + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListUpdate(User listOwner, UserList list) {
            System.out.println("onUserListUpdated listOwner:@"
                    + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserListDeletion(User listOwner, UserList list) {
            System.out.println("onUserListDestroyed listOwner:@"
                    + listOwner.getScreenName()
                    + " list:" + list.getName());
        }
        public void onUserProfileUpdate(User updatedUser) {
            System.out.println("onUserProfileUpdated user:@" + updatedUser.getScreenName());
        }
        public void onBlock(User source, User blockedUser) {
            System.out.println("onBlock source:@" + source.getScreenName()
                    + " target:@" + blockedUser.getScreenName());
        }
        public void onUnblock(User source, User unblockedUser) {
            System.out.println("onUnblock source:@" + source.getScreenName()
                    + " target:@" + unblockedUser.getScreenName());
        }
        public void onException(Exception ex) {
            ex.printStackTrace();
            System.out.println("onException:" + ex.getMessage());
        }
    };