code: @Override
      public void onEvent(Map<String, String> param) throws SubscriberException {
          try {
              addToIndex(param);
          } catch (Exception e) {
              throw new SubscriberException("Fail to add log to solr"
                      + e.getMessage());
          }
      }
docs: Method to fire for incoming events
  
  @param param : Map of key/value pairs to add to the index
  @throws SubscriberException if there was an error