code: public StringBuilder formatMeasures(
              StringBuilder appendTo, FieldPosition fieldPosition, Measure... measures) {
          // fast track for trivial cases
          if (measures.length == 0) {
              return appendTo;
          }
          if (measures.length == 1) {
              return formatMeasure(measures[0], numberFormat, appendTo, fieldPosition);
          }
  
          if (formatWidth == FormatWidth.NUMERIC) {
              // If we have just hour, minute, or second follow the numeric
              // track.
              Number[] hms = toHMS(measures);
              if (hms != null) {
                  return formatNumeric(hms, appendTo);
              }
          }
  
          ListFormatter listFormatter = ListFormatter.getInstance(
                  getLocale(), formatWidth.getListFormatterStyle());
          if (fieldPosition != DontCareFieldPosition.INSTANCE) {
              return formatMeasuresSlowTrack(listFormatter, appendTo, fieldPosition, measures);
          }
          // Fast track: No field position.
          String[] results = new String[measures.length];
          for (int i = 0; i < measures.length; i++) {
              results[i] = formatMeasure(
                      measures[i],
                      i == measures.length - 1 ? numberFormat : integerFormat);
          }
          return appendTo.append(listFormatter.format((Object[]) results));
  
      }
docs: Formats a sequence of measures.
  
  If the fieldPosition argument identifies a NumberFormat field,
  then its indices are set to the beginning and end of the first such field
  encountered. MeasureFormat itself does not supply any fields.
  
  @param appendTo the formatted string appended here.
  @param fieldPosition Identifies a field in the formatted text.
  @param measures the measures to format.
  @return appendTo.
  @see MeasureFormat#formatMeasures(Measure...)