How to set formulas in cells using Apache POI?

Question

I am currently using Apache POI for Java to set formulas in cells.

But after I run the program and open the Excel file that I created and processed, the cells with t

Answer 1

I was having the similar problem and "SUM(B4:B20)" does not work for me directly as the sheet was generated dynamically. The problem was with the cell reference.

On the basis of https://stackoverflow.com/a/2339262/2437655 and https://stackoverflow.com/a/33098060/2437655 I was able to generate the actual formula. e.g.

 val totalProductQtyPerUserCell = userDetailsRow.createCell(products.size + 1)
 totalProductQtyPerUserCell.cellType = HSSFCell.CELL_TYPE_FORMULA
 totalProductQtyPerUserCell.cellFormula = "SUM(${CellReference.convertNumToColString(1)}${totalProductQtyPerUserCell.row.rowNum + 1}:${CellReference.convertNumToColString(products.size)}${totalProductQtyPerUserCell.row.rowNum + 1})"

Hope that help.