code: public static void setupLogging(boolean console)
    {
      LoggerContext loggerContext = (LoggerContext) LoggerFactory.
        getILoggerFactory();
  
      JoranConfigurator jc = new JoranConfigurator();
      jc.setContext(loggerContext);
      loggerContext.reset();
      try
      {
        jc.doConfigure(System.getProperty("annis.home")
          + "/conf/logback.xml");
      }
      catch (JoranException ex)
      {
        System.out.println(ex.getMessage());
      }
  
      ConsoleAppender<ILoggingEvent> consoleAppender = new ConsoleAppender<>();
      consoleAppender.setContext(loggerContext);
      consoleAppender.setName("CONSOLE");
  
      consoleAppender.setLayout(new ConsoleLayout());
  
      ThresholdFilter consoleFilter = new ConsoleFilter();
  
      consoleFilter.setLevel(console ? "DEBUG" : "WARN");
      consoleFilter.start();
  
      consoleAppender.addFilter(consoleFilter);
      consoleAppender.setTarget("System.err");
      consoleAppender.start();
  
      ch.qos.logback.classic.Logger logbackLogger = loggerContext.getLogger(
        Logger.ROOT_LOGGER_NAME);
  
      logbackLogger.addAppender(consoleAppender);
  
      SLF4JBridgeHandler.removeHandlersForRootLogger();;
      SLF4JBridgeHandler.install();
    }
docs: configure logging