code: public static String getCellValue(Cell c) {
          String o;
          switch (c.getCellTypeEnum()) {
              case BLANK:
                  o = "";
                  break;
              case BOOLEAN:
                  o = String.valueOf(c.getBooleanCellValue());
                  break;
              case FORMULA:
                  o = calculationFormula(c);
                  break;
              case NUMERIC:
                  if (DateUtil.isCellDateFormatted(c)) {
                      o = DateUtils.date2Str(c.getDateCellValue());
                  } else {
                      o = String.valueOf(c.getNumericCellValue());
                      o = matchDoneBigDecimal(o);
                      o = RegularUtils.converNumByReg(o);
                  }
                  break;
              case STRING:
                  o = c.getStringCellValue();
                  break;
              default:
                  o = null;
                  break;
          }
          return o;
      }
docs: 获取单元格内容
  
  @param c 单元格
  @return 单元格内容