code: static void formatBadLogData(
        RuntimeException error, LogData badLogData, SimpleLogHandler receiver) {
      StringBuilder errorMsg =
          new StringBuilder("LOGGING ERROR: ").append(error.getMessage()).append('\n');
      int length = errorMsg.length();
      try {
        appendLogData(badLogData, errorMsg);
      } catch (RuntimeException e) {
        // Reset partially written buffer when an error occurs.
        errorMsg.setLength(length);
        errorMsg.append("Cannot append LogData: ").append(e);
      }
  
      // Re-target this log message as a warning (or above) since it indicates a real bug.
      Level level =
          badLogData.getLevel().intValue() < WARNING.intValue() ? WARNING : badLogData.getLevel();
  
      receiver.handleFormattedLogMessage(level, errorMsg.toString(), error);
    }
docs: Formats the log message in response to an exception during a previous logging attempt. A
  synthetic error message is generated from the original log data and the given exception is set
  as the cause. The level of this record is the maximum of WARNING or the original level.