@VisibleForTesting
    static void validateIntervalFreshness(IntervalFreshness intervalFreshness) {
        if (!NumberUtils.isParsable(intervalFreshness.getInterval())) {
            throw new ValidationException(
                    String.format(
                            "The interval freshness value '%s' is an illegal integer type value.",
                            intervalFreshness.getInterval()));
        }

        if (!NumberUtils.isDigits(intervalFreshness.getInterval())) {
            throw new ValidationException(
                    "The freshness interval currently only supports integer type values.");
        }
    }
@Test
    void testIllegalIntervalFreshness() {
        assertThatThrownBy(() -> validateIntervalFreshness(IntervalFreshness.ofMinute("2efedd")))
                .isInstanceOf(ValidationException.class)
                .hasMessageContaining(
                        "The interval freshness value '2efedd' is an illegal integer type value.");

        assertThatThrownBy(() -> validateIntervalFreshness(IntervalFreshness.ofMinute("2.5")))
                .isInstanceOf(ValidationException.class)
                .hasMessageContaining(
                        "The freshness interval currently only supports integer type values.");
    }