public static long validateExpiration(String claimName, Long claimValue) throws ValidateException {
        if (claimValue == null)
            throw new ValidateException(String.format("%s value must be non-null", claimName));

        if (claimValue < 0)
            throw new ValidateException(String.format("%s value must be non-negative; value given was \"%s\"", claimName, claimValue));

        return claimValue;
    }
@Test
    public void testValidateExpirationDisallowsNull() {
        assertThrows(ValidateException.class, () -> ClaimValidationUtils.validateExpiration("exp", null));
    }