code: protected void onServiceInstanceAvailable(ServiceInstance instance){
          String serviceName = instance.getServiceName();
          synchronized(notificationHandlers){
              if(notificationHandlers.containsKey(serviceName)){
                  for(NotificationHandler h : notificationHandlers.get(serviceName)){
                      h.serviceInstanceAvailable(instance);
                  }
              }
          }
      }
docs: On a ServiceInstance Unavailable.
  
  It will invoke the serviceInstanceAvailable of the NotificationHandler.
  
  @param instance
  the ServiceInstance.