code: public static MyfacesLogger createMyfacesLogger(Class<?> c) 
      {
          if (c == null)
          {
              throw new IllegalArgumentException(_LOG.getMessage(
                      "CLASS_REQUIRED"));
          }
          String name = c.getName();
          return createMyfacesLogger(name);
      }
docs: Find or create a logger for a named subsystem.  If a logger has
  already been created with the given name it is returned.  Otherwise
  a new logger is created.
  <p>
  If a new logger is created its log level will be configured
  based on the LogManager configuration and it will configured
  to also send logging output to its parent's handlers.  It will
  be registered in the LogManager global namespace.
  
  @param c       A class instance for the logger.
  @return a suitable Logger