public final Filterer createCustomFilter(final String implementor, final String[] params) throws CustomFilterException {
		Class<Filterer> customClassToCreate = Filterer.class;
		Filterer custom = customClassToCreate.cast(createCustom(implementor, params, customClassToCreate));
		if (custom == null) {
			throw new CustomFilterException();
		}
		return custom;
	}