code: public Object read() {
      HSSFSheet sheet = workbook.getSheetAt(sheetNum);
      if (indexInSheet > sheet.getLastRowNum()) { return null; }
      HSSFRow row = sheet.getRow(indexInSheet);
      indexInSheet++;
      // 如果是个空行,返回空记录
      if (row == null) {
        return new Object[attrCount];
      } else {
        Object[] values = new Object[((attrCount != 0) ? attrCount : row.getLastCellNum())];
        for (int k = 0; k < values.length; k++) {
          values[k] = getCellValue(row.getCell(k));
        }
        return values;
      }
    }
docs: <p>
  read.
  </p>
  
  @return a {@link java.lang.Object} object.