code: public void refreshAppAuthTicket() {
  
          StringBuilder resourceUrl = new StringBuilder(MozuConfig.getBaseUrl()).append(AuthTicketUrl.refreshAppAuthTicketUrl(null).getUrl());
  
          try {
              @SuppressWarnings("unchecked")
              MozuClient<AuthTicket> client = (MozuClient<AuthTicket>) MozuClientFactory.getInstance(AuthTicket.class);
      
              AuthTicketRequest authTicketRequest = new AuthTicketRequest();
              authTicketRequest.setRefreshToken(appAuthTicket.getRefreshToken());
              
              appAuthTicket = client.executePutRequest(authTicketRequest, resourceUrl.toString(), null);
          } catch (ApiException e) {
              logger.warn(e.getMessage(), e);
              throw e;
          } catch (Exception e) {
              logger.warn(e.getMessage(), e);
              throw new ApiException("Exception getting Mozu client: " + e.getMessage());
          }
  
          logger.info("Setting app token refresh intervals");
          setRefreshIntervals(false);
          logger.info("App Authentication Done");
      }
docs: jh the application auth ticket using the refresh token