@Override
    public void clean() {
        lock.tryLock(__ -> {
            val now = ZonedDateTime.now(ZoneId.systemDefault());
            LOGGER.debug("Starting to clean previously used authenticator tokens from [{}] at [{}]", tokenRepository, now);
            tokenRepository.clean();
            LOGGER.debug("Finished cleaning authenticator tokens at [{}]", now);
        });

    }
This is {@link OneTimeTokenRepositoryCleaner}.

@author Misagh Moayyed
@since 5.1.0
support/cas-server-support-otp-mfa-core/src/main/java/org/apereo/cas/otp/repository/token/OneTimeTokenRepositoryCleaner.java