@Override
    public boolean isClientSecretExpired(final OAuthRegisteredService registeredService) {
        if (registeredService instanceof final OidcRegisteredService oidcService && oidcService.getClientSecretExpiration() > 0) {
            val expirationTime = DateTimeUtils.zonedDateTimeOf(Instant.ofEpochSecond(oidcService.getClientSecretExpiration()));
            val currentTime = ZonedDateTime.now(ZoneOffset.UTC);
            LOGGER.debug("Client secret is set to expire at [{}], while now is [{}]", expirationTime, currentTime);
            if (currentTime.isAfter(expirationTime)) {
                LOGGER.warn("Client secret for service [{}] has expired at [{}] and must be renewed",
                    oidcService.getName(), expirationTime);
                return true;
            }
        }
        return false;
    }
This is {@link OidcClientSecretValidator}.

@author Misagh Moayyed
@since 6.6.0
support/cas-server-support-oidc-core-api/src/main/java/org/apereo/cas/oidc/web/OidcClientSecretValidator.java