code: private synchronized void findHealthService(final HttpServletRequest request) throws ServletException {
  
          if (healthService == null) {
              HttpSession session = request.getSession();
              ServletContext sc = session.getServletContext();
              BundleContext ctxt = (BundleContext) sc.getAttribute("osgi-bundlecontext");
  
              ServiceReference<HealthCheckService> ref = ctxt.getServiceReference(HealthCheckService.class);
              if (ref == null) {
                  logger.log(Level.SEVERE, "healthcheck.CWMH0000E", "HealthCheckService");
                  throw new ServletException(Tr.formatMessage(tc, "OSGI_SERVICE_ERROR", "HealthCheckService"));
              } else {
                  healthService = ctxt.getService(ref);
              }
          }
      }
docs: {@inheritDoc}