[java] Apache POI Excel - how to configure columns to be expanded?

I am using Apache POI API to generate excel spreadsheet to output some data.

The problem I am facing is when the spreadsheet is created and opened, columns are not expanded so that some long text like Date formatted text is not showing up on first glance.

I could just double click the column border in excel to expand or drag the border to adjust the column width but there could be 20+ columns and there is no way I want to do that manually every time I open the spreadsheet :(

I found out (though could be wrong method) groupRow() and setColumnGroupCollapsed() might be able to do the trick but no luck. Maybe I'm using it in wrong way.

Sample Code snippet

        Workbook wb = new HSSFWorkbook();
        CreationHelper createHelper = wb.getCreationHelper();
        //create sheet
        Sheet sheet = wb.createSheet("masatoSheet");

        //not really working yet.... :(
        //set group for expand/collapse
        //sheet.groupRow(0, 10); //just random fromRow toRow argument values...
        //sheet.setColumnGroupCollapsed(0, true);

        //create row
        Row row = sheet.createRow((short)0);
        //put a cell in the row and store long text data
        row.createCell(0).setCellValue("Loooooooong text not to show up first");

When this spreadsheet is created, the "Looooooong text not to show up first" string is in the cell but since the column is not expanded only "Loooooooo" is showing up.

How can I configure it so that when I open my spreadsheet, the column is already expanded???

I use below simple solution:

This is your workbook and sheet:

XSSFWorkbook workbook = new XSSFWorkbook();
XSSFSheet sheet = workbook.createSheet("YOUR Workshhet");

then add data to your sheet with columns and rows. Once done with adding data to sheet write following code to autoSizeColumn width.

for (int columnIndex = 0; columnIndex < 15; columnIndex++) {
                    sheet.autoSizeColumn(columnIndex);
                }

Here, instead 15, you add the number of columns in your sheet.

Hope someone helps this.

sample code below

HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet = wb.createSheet("your sheet name");
HSSFRow row = sheet.createRow(0);

cell = row.createCell(0);
cell.setCellValue("A BIG NAME WITH AUTO SIZE FEATURE ENABLED");

//this is crucial

sheet.autoSizeColumn(0);

//argument must be cell number

cell = row.createCell(1);
cell.setCellValue("a big name without auto size feature enabled");

Check the output and go nuts :)

If you want to auto size all columns in a workbook, here is a method that might be useful:

public void autoSizeColumns(Workbook workbook) {
    int numberOfSheets = workbook.getNumberOfSheets();
    for (int i = 0; i < numberOfSheets; i++) {
        Sheet sheet = workbook.getSheetAt(i);
        if (sheet.getPhysicalNumberOfRows() > 0) {
            Row row = sheet.getRow(sheet.getFirstRowNum());
            Iterator<Cell> cellIterator = row.cellIterator();
            while (cellIterator.hasNext()) {
                Cell cell = cellIterator.next();
                int columnIndex = cell.getColumnIndex();
                sheet.autoSizeColumn(columnIndex);
            }
        }
    }
}

Its very simple, use this one line code dataSheet.autoSizeColumn(0)

or give the number of column in bracket dataSheet.autoSizeColumn(cell number )

You can add this, after your loop.

for (int i = 0; i<53;i++) {
    sheet.autoSizeColumn(i);
}

Tip : To make Auto size work , the call to sheet.autoSizeColumn(columnNumber) should be made after populating the data into the excel.

Calling the method before populating the data, will have no effect.

You can use setColumnWidth() if you want to expand your cell more.

You can wrap the text as well. PFB sample code:

CellStyle wrapCellStyle = new_workbook.createCellStyle();
                    wrapCellStyle.setWrapText(true);

For Excel POI:

sheetName.autoSizeColumn(cellnum); 

You can try something like this:

HSSFSheet summarySheet = wb.createSheet();
summarySheet.setColumnWidth(short column, short width);

Here params are:column number in sheet and its width But,the units of width are pretty small, you can try 4000 for example.

If you know the count of your columns (f.e. it's equal to a collection list). You can simply use this one liner to adjust all columns of one sheet (if you use at least java 8):

IntStream.range(0, columnCount).forEach((columnIndex) -> sheet.autoSizeColumn(columnIndex));