code: public void printWarning(int daysBeforeExpireWarning, String keyStoreName, String alias, X509Certificate cert) {
          try {
              long millisDelta = ((((daysBeforeExpireWarning * 24L) * 60L) * 60L) * 1000L);
              long millisBeforeExpiration = cert.getNotAfter().getTime() - System.currentTimeMillis();
              long daysLeft = ((((millisBeforeExpiration / 1000L) / 60L) / 60L) / 24L);
  
              // cert is already expired
              if (millisBeforeExpiration < 0) {
                  Tr.error(tc, "ssl.expiration.expired.CWPKI0017E", new Object[] { alias, keyStoreName });
              } else if (millisBeforeExpiration < millisDelta) {
                  Tr.warning(tc, "ssl.expiration.warning.CWPKI0016W", new Object[] { alias, keyStoreName, Long.valueOf(daysLeft) });
              } else {
                  if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())
                      Tr.debug(tc, "The certificate with alias " + alias + " from keyStore " + keyStoreName + " has " + daysLeft + " days left before expiring.");
              }
          } catch (Exception e) {
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())
                  Tr.debug(tc, "Exception reading KeyStore certificates during expiration check; " + e);
              FFDCFilter.processException(e, getClass().getName(), "printWarning", this);
          }
      }
docs: Print a warning about a certificate being expired or soon to be expired in
  the keystore.
  
  @param daysBeforeExpireWarning
  @param keyStoreName
  @param alias
  @param cert