docs: private String expandMessage(final BuildEvent event, final String message) {
          final HashMap<String,String> data=new HashMap<String, String>();
  
          final String user = retrieveUserName(event);
          if(null!=user){
              data.put("user", user);
          }
          final String node = retrieveNodeName(event);
          if(null!=node){
              data.put("node", node);
          }
          data.put("level", logLevelToString(event.getPriority()));
          if(null!=formatter){
  
              return formatter.reformat(data, message);
          }else {
              return message;
          }
      }