code: @SuppressWarnings("unchecked")
    public static void init(boolean mustLog) {
      if ((hasToLog == null || hasToLog != mustLog) && mustLog) {
        synchronized (LoggerFactory.class) {
          if (hasToLog == null || hasToLog != mustLog) {
            try {
              Class.forName("org.slf4j.LoggerFactory");
              hasToLog = Boolean.TRUE;
            } catch (ClassNotFoundException classNotFound) {
              System.out.println("Logging cannot be activated, missing slf4j dependency");
              hasToLog = Boolean.FALSE;
            }
          }
        }
      }
  
    }
docs: Initialize factory.
  
  @param mustLog indicate if must initiate Slf4j log