code: protected boolean validateExpiration(SignedJWT jwtToken) {
          boolean valid = false;
          try {
              Date expires = jwtToken.getJWTClaimsSet().getExpirationTime();
              if (expires == null || new Date().before(expires)) {
                  if (LOG.isDebugEnabled()) {
                      LOG.debug("SSO token expiration date has been successfully validated");
                  }
                  valid = true;
              } else {
                  LOG.warn("SSO expiration date validation failed.");
              }
          } catch (ParseException pe) {
              LOG.warn("SSO expiration date validation failed.", pe);
          }
          return valid;
      }
docs: Validate that the expiration time of the JWT token has not been violated.
  If it has then throw an AuthenticationException. Override this method in
  subclasses in order to customize the expiration validation behavior.
  
  @param jwtToken the token that contains the expiration date to validate
  @return valid true if the token has not expired; false otherwise