code: @Reference(service = ServerStarted.class,
                 policy = ReferencePolicy.DYNAMIC,
                 cardinality = ReferenceCardinality.OPTIONAL,
                 policyOption = ReferencePolicyOption.GREEDY)
      protected void setServerStarted(ServiceReference<ServerStarted> ref) {
  
          // We don't want to start the polling task if we haven't been activated yet.
  
          // Not starting polling if not executing tasks.  Need to coordinate with activate.
          if (readyForPollingTask.addAndCheckIfReady(PollingManager.SERVER_STARTED))
              startPollingTask(configRef.get());
      }
docs: Declarative services method that is invoked once the server is started.
  Only after this method is invoked is the initial polling for
  persistent tasks performed.
  
  @param ref reference to the ServerStarted service