@Override
        public Class<E> enumClass() {
            return inner.enumClass();
        }
Internal class used when calling {@code ToEnumNullable.doubleOrElse(enum)}.

@param <T>  the input entity type
@param <E>  the enum type
runtime-parent/runtime-compute/src/main/java/com/speedment/runtime/compute/internal/expression/OrElseGetUtil.java