code: public static void removeFavorite(@Nonnull User user, @Nonnull Item item) throws FavoriteException {
          try {
              if (isFavorite(user, item)) {
                  FavoriteUserProperty fup = user.getProperty(FavoriteUserProperty.class);
                  fup.removeFavorite(item.getFullName());
                  FavoriteListener.fireOnRemoveFavourite(item, user);
              } else {
                  throw new FavoriteException("Favourite is already unset for User: <" + user.getFullName() + "> Item: <" + item.getFullName() + ">");
              }
          } catch (IOException e) {
              throw new FavoriteException("Could not remove Favorite. User: <" + user.getFullName() + "> Item: <" + item.getFullName() + ">", e);
          }
      }
docs: Remove an item as a favorite for a user
  Fires {@link FavoriteListener#fireOnRemoveFavourite(Item, User)}
  @param user to remove the favorite from
  @param item to favorite
  @throws FavoriteException