code: public static void log(@Nonnull Logger logger, @Nonnull LogLevel level, @Nonnull String format, @Nullable Object arg) {
          if (logger instanceof LocationAwareLogger) {
              log((LocationAwareLogger) logger, level, FQCN, null, format, new Object[]{arg}, null);
          } else if (trace.equals(level)) {
              logger.trace(format, arg);
          } else if (debug.equals(level)) {
              logger.debug(format, arg);
          } else if (info.equals(level)) {
              logger.info(format, arg);
          } else if (warning.equals(level)) {
              logger.warn(format, arg);
          } else if (error.equals(level) || fatal.equals(level)) {
              logger.error(format, arg);
          } else {
              log(logger, normalize(level), format, arg);
          }
      }
docs: <p>Log a message at the given <code>level</code> according to the specified format and argument.</p>
  
  <p>This form avoids superfluous object creation when the logger is disabled for the given <code>level</code>.</p>
  
  @param format the format string
  @param arg the argument