Sheet sheet = workbook.getSheetAt(0);
sheet.autoSizeColumn(0); //adjust width of the first column
sheet.autoSizeColumn(1); //adjust width of the second column
For SXSSFWorkbooks only, because the random access window is likely to exclude most of the rows in the worksheet, which are needed for computing the best-fit width of a column, the columns must be tracked for auto-sizing prior to flushing any rows.
SXSSFWorkbook workbook = new SXSSFWorkbook();
SXSSFSheet sheet = workbook.createSheet();
sheet.trackColumnForAutoSizing(0);
sheet.trackColumnForAutoSizing(1);
// If you have a Collection of column indices, see SXSSFSheet#trackColumnForAutoSizing(Collection<Integer>)
// or roll your own for-loop.
// Alternatively, use SXSSFSheet#trackAllColumnsForAutoSizing() if the columns that will be auto-sized aren't
// known in advance or you are upgrading existing code and are trying to minimize changes. Keep in mind
// that tracking all columns will require more memory and CPU cycles, as the best-fit width is calculated
// on all tracked columns on every row that is flushed.
// create some cells
for (int r=0; r < 10; r++) {
Row row = sheet.createRow(r);
for (int c; c < 10; c++) {
Cell cell = row.createCell(c);
cell.setCellValue("Cell " + c.getAddress().formatAsString());
}
}
// Auto-size the columns.
sheet.autoSizeColumn(0);
sheet.autoSizeColumn(1);
Note, that Sheet#autoSizeColumn() does not evaluate formula cells, the width of formula cells is calculated based on the cached formula result. If your workbook has many formulas then it is a good idea to evaluate them before auto-sizing.