Merging cells in Excel using Apache POI - Dustbiin

Merge cells in a row or merge cells in column -

Create a workbook and sheet in the workbook-

XSSFWorkbook workBook = new XSSFWorkbook();

Sheet sheet = workBook.createSheet("My sheet");

sheet.addMergedRegion(new CellRangeAddress(startRowIndx, 

                                           endRowIndx, 

                                           startColIndx, 

                                           endColIndx));

try (FileOutputStream outputStream = new FileOutputStream( "demo.xlsx" ))

{
    workbook.write( outputStream );

}
finally
{
    workbook.close();
}

Make sure the CellRangeAddress does not coincide with other merged regions as that will throw an exception.

• If you want to merge cells one above another, keep column indexes same
• If you want to merge cells which are in a single row, keep the row indexes same
• Indexes are zero-based, it means row and column start from zero.
• Start index of row and column must be less the end index of row and column.