code: @Override
  	public synchronized String format(LogRecord record) {
          // clear string builder content of previous runs
          BUILDER.setLength(0);
  
          // build log message
          appendDateTime(record);
          appendApplication();
          appendLevel(record);
          appendClass(record);
          appendMessage(record);
          appendThrowable(record);
          appendNewLine();
  
          return BUILDER.toString();
      }
docs: Format the given LogRecord.
  
  @param record the log record to be formatted.
  @return a formatted log record