code: public static ICellValue resolveCellValue(org.apache.poi.ss.usermodel.CellValue cellval) {
          if (cellval == null) { return CellValue.BLANK; }
  
          switch (cellval.getCellType()) {
              case CELL_TYPE_NUMERIC: { return CellValue.from(cellval.getNumberValue()); }
              case CELL_TYPE_STRING: { return CellValue.from(cellval.getStringValue()); }
              case CELL_TYPE_BOOLEAN: { return CellValue.from(cellval.getBooleanValue()); }
              case CELL_TYPE_ERROR: { return CellValue.from(ErrorEval.valueOf(cellval.getErrorValue()).getErrorString()); }
              case CELL_TYPE_BLANK: { return CellValue.BLANK; }
              case CELL_TYPE_FORMULA: { throw new CalculationEngineException("Result of evaluation cannot be a formula."); }
              default: { throw new CalculationEngineException(String.format("CellValue's tType %s is not supported.", cellval.getCellType())); }
          }
      }
docs: Returns the new {@link CellValue} from provided {@link org.apache.poi.ss.usermodel.CellValue}.