How do I set cell value to Date and apply default Excel date format?

Question

I\'ve been using Apache POI for some time to read existing Excel 2003 files programmatically. Now I have a new requirement to create entire .xls files in-memory (still using

Answer 1

To set to default Excel type Date (defaulted to OS level locale /-> i.e. xlsx will look different when opened by a German or British person/ and flagged with an asterisk if you choose it in Excel's cell format chooser) you should:

    CellStyle cellStyle = xssfWorkbook.createCellStyle();
    cellStyle.setDataFormat((short)14);
    cell.setCellStyle(cellStyle);

I did it with xlsx and it worked fine.