Apache poi. Formula evalution. evaluteAll vs setForceFormulaRecalculation

Question

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Problem: i use formulas in my workBook.xlsx. Depending on the circumstances i change value (3,3). At this example i changed 10 to 20. And after that i want to calculate the formula, which use this cell. When it has finished, it will override the value of the cells, remove formula and record the value. This cell no longer be used for the calculations again.

Code:

public class ReaderXlsx {
    public List<List<String>> ReaderXlsx(String sfilename, int firstColumn, int columnsCount, int rowsCount, int moduleCount){
        int lastColumn=firstColumn+columnsCount;
        List<List<String>> rowsContent = new ArrayList<List<String>>();
        try ( FileInputStream fileInputStream = new FileInputStream("C:\\Users\\student3\\"+sfilename+".xlsx");)
        {
            XSSFWorkbook workBook = new XSSFWorkbook(fileInputStream);
            XSSFSheet sheet = workBook.getSheetAt(0);
            int firstRow = findOneInFirstColumn(sheet,50);
            setModuleCount(sheet,moduleCount);
            workBook.getCreationHelper().createFormulaEvaluator().evaluateAll();

            toNewLine:
            for (int lineId=firstRow;lineId<rowsCount;lineId++)            {
                List<String> columnsContent = new ArrayList<String>();
                Row row = sheet.getRow(lineId);
                if (row==null){continue toNewLine;}
                if (row.getCell(2)==null || row.getCell(2).getStringCellValue().equals("") ) {continue toNewLine;}
                    for (int columnId=firstColumn+1;columnId<lastColumn;columnId++)     {
                        Cell cell = row.getCell(columnId-1);
                        if ((cell==null)) { continue toNewLine;}
                        cell.setCellType(Cell.CELL_TYPE_STRING);
                        if ((columnId==0 & cell.getStringCellValue().equals(""))) {continue toNewLine;}
                        if ((columnId==5 & cell.getStringCellValue().equals("")) || (columnId==6 & cell.getStringCellValue().equals("")))  cell.setCellValue("0");
                        columnsContent.add(cell.getStringCellValue());
                    }
                rowsContent.add(columnsContent);
            }
            try(FileOutputStream out = new FileOutputStream("C:\\Users\\student3\\Used"+sfilename+".xlsx"); ) {
                workBook.write(out);
                out.close();         }
        }
        catch (IOException e) {
            e.printStackTrace();
        }
        return rowsContent;
    }
    private Integer findOneInFirstColumn(XSSFSheet sheet, Integer maxRows){
        int result=0;
        toNextLine:
        for (int lineId=0;lineId<maxRows;lineId++){
        Row row = sheet.getRow(lineId);
            if (row==null | row.getCell(0)==null) {result++; continue toNextLine; }
            else{
                row.getCell(0).setCellType(Cell.CELL_TYPE_STRING);
                if (row.getCell(0).getStringCellValue().equals("1")){return result;}
                else {result++;}
            }
        }
        return result;
    }
    private void setModuleCount(XSSFSheet sheet, Integer moduleCount){
        Row row = sheet.getRow(1);
        if (moduleCount==0) {}
        if (moduleCount>0) {row.createCell(2).setCellValue(moduleCount.toString());}
    }

}

Now i use 2 files, because i need to save my formulas. I want to use only 1 (source) and update it correctly.