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How can Apache POI use formulas in streaming mode?

I am using Apache POI 3.17 (current). When I use HSSFCell.setFormula() to insert a formula like "A1+17" it works. When I do the same in streaming mode, using SXSSFCell.setFormula() the formula appears (with a leading "=") in the input line but the displayed result in the cell is always 0.
I tried with the cell types NUMERIC and FORMULA. Here is my minimal not working example:
final SXSSFWorkbook wb = new SXSSFWorkbook();
final SXSSFSheet sheet = wb.createSheet("Test-S");
final SXSSFRow row = sheet.createRow(0);
final SXSSFCell cell1 = row.createCell(0);
cell1.setCellType(CellType.NUMERIC);
cell1.setCellValue(124);
final SXSSFCell formulaCell1 = row.createCell(1);
formulaCell1.setCellType(CellType.FORMULA);
formulaCell1.setCellFormula("A1 + 17");
final SXSSFCell formulaCell2 = row.createCell(2);
formulaCell2.setCellType(CellType.NUMERIC);
formulaCell2.setCellFormula("A1+18");
FileOutputStream os = new FileOutputStream("/tmp/test-s.xlsx");
wb.write(os);
wb.close();
os.close();
The three cells display as 124/0/0, although in the input line the formulae are displayed correctly.
Any hints are appreciated.

It works for me with Excel 2016, I get the correct results in the cells when I open the sample file. Probably older versions of Excel handle this slightly differently, please try to force evaluation of formulas with the following two things
// evaluate all formulas and store cached results
wb.getCreationHelper().createFormulaEvaluator().evaluateAll();
// suggest to Excel to recalculate the formulas itself as well
sheet.setForceFormulaRecalculation(true);
Hopefully one of those two will make it work for you as well.

The answers does not answer the question why this problem with OpenOffice/Libreoffice only occurs if SXSSFCell is used as a formula cell. When using XSSFCell as a formula cell it does not occur.
The answer is that SXSSFCell always uses a cell value, even if the formula was not evaluated at all. And the worst thing is that it uses the value 0 (zero) if if the formula was not evaluated at all. This is a fundamental misusing of the value 0 in mathematics. The value 0 explicitly does not mean that there is not a value or that there is a unknown value. It means that there is the value 0 and nothing else. So the value 0 should not be used as the cached formula result of a not evaluated formula. Instead no value should be used until the formula is evaluated. Exact as XSSFCell does.
So the really correct answer must be that apache poi should correct their SXSSFCell code.
Workaround until this:
import java.io.FileOutputStream;
import org.apache.poi.xssf.streaming.*;
import org.apache.poi.ss.usermodel.CellType;
import java.lang.reflect.Field;
import java.util.TreeMap;
public class CreateExcelSXSSFFormula {
public static void main(String[] args) throws Exception {
SXSSFWorkbook wb = new SXSSFWorkbook();
SXSSFSheet sheet = wb.createSheet("Test-S");
SXSSFRow row = sheet.createRow(0);
SXSSFCell cell = row.createCell(0);
cell.setCellValue(124);
SXSSFFormulaonlyCell formulacell = new SXSSFFormulaonlyCell(row, 1);
formulacell.setCellFormula("A1+17");
cell = row.createCell(2);
cell.setCellFormula("A1+17");
formulacell = new SXSSFFormulaonlyCell(row, 3);
formulacell.setCellFormula("A1+18");
cell = row.createCell(4);
cell.setCellFormula("A1+18");
wb.write(new FileOutputStream("test-s.xlsx"));
wb.close();
wb.dispose();
}
private static class SXSSFFormulaonlyCell extends SXSSFCell {
SXSSFFormulaonlyCell(SXSSFRow row, int cellidx) throws Exception {
super(row, CellType.BLANK);
Field _cells = SXSSFRow.class.getDeclaredField("_cells");
_cells.setAccessible(true);
#SuppressWarnings("unchecked") //we know the problem and expect runtime error if it possibly occurs
TreeMap<Integer, SXSSFCell> cells = (TreeMap<Integer, SXSSFCell>)_cells.get(row);
cells.put(cellidx, this);
}
#Override
public CellType getCachedFormulaResultTypeEnum() {
return CellType.BLANK;
}
}
}

Of course I should have mentioned that I use LibreOffice. I have now found that LibreOffice intentionally does not recalculate formulae from an Excel-created sheet, and it considers POI sheets as Excel-created.
See https://ask.libreoffice.org/en/question/12165/calc-auto-recalc-does-not-work/ .
Changing the LibreOffice settings (Tools – Options – LibreOffice Calc – formula – Recalculation on file load) helps.

Data not getting printed in excel sheet after using formula

I am trying to use XSSFRow to use data from one sheet to other,here is the code
XSSFRow r = nfrntSheet.getRow(i);
Cell c = r.createCell(7);
c.setCellFormula("'Original'!F"+(i+1)+"+'Original'!G"+(i+1)+"*-1");
After computing the formula the data in the written sheet will be displaced like "#value" instead of the number.
what should i do to so that original data is displayed instead of the "#value"

you need to set the cell type
c.setCellType(XSSFCell.CELL_TYPE_FORMULA);
so as per your code
XSSFRow r = nfrntSheet.getRow(i);
Cell c = r.createCell(7);
c.setCellType(XSSFCell.CELL_TYPE_FORMULA);
c.setCellFormula("'Original'!F"+(i+1)+"+'Original'!G"+(i+1)+"*-1");

How to get the Excel sheet cell data by column name in using apache POI library

I want to get the cell data of a particular sheet with column name rather than column index,
Currently i can get the cell data using
fis = new FileInputStream(ExcelPath);
wb = new XSSFWorkbook(fis);
sh = wb.getSheet(SheetName);
cell = sh.getRow(rownum).getCell(colnum);
but I am looking for a way where I can get the cell data by,
cell = sh.getRow(rownum).getCell(ColName); //not working

Excel columns don't have names. They only have letters, eg A, D, BB
To work out how to map an Excel-style column letter into a POI-style 0-based index, you need to use the method convertColStringToIndex(java.lang.String ref) which does it for you
If you mean you want to lookup a column based on the value held in the first row, you should do something like:
DataFormatter fmt = new DataFormatter();
Map<String,Integer> headings = new HashMap<String,Integer>();
Row headings = sheet.getRow(0);
if (headings == null) throw new IllegalArgumentException("Empty headings row");
for (Cell c : headings) {
headings.put(fmt.formatCellValue(c), c.getColumnIndex());
}
If you have more complex use cases, such as a heading running over multiple rows, you'll need to write more complex code... It's all driven by your use-case

How to do Excel's "Convert to Number" in Java

I am reading data from Excel using Apache POI. I want to convert some cells to number while reading in Java as following:
Input 01.0234500
Output 1.02345
Input 412206362371
Output 4.12206E+11
Input 1234.201400002345
Output 1234.2014
When I am using "Convert to Number" in Excel, it works fine. But I want the same output while reading Excel cells in Java.
It can also be achieved using =VALUE() function in Excel. But how do I implement the same functionality in Java?

I think there are a number of ways to accomplish what you stipulate, but the most direct method is just to use the VALUE() function and then evaluate it. This certainly is not the most efficient method, but it works.
Essentially we just read in the value of the input cell, then create a new cell formula cell which contains the VALUE() function with the original value as the parameter. After that we call evalutateInCell to evaluate the VALUE() function and replace the cell value with the results.
XSSFWorkbook wb = new XSSFWorkbook();
XSSFSheet sheet = wb.createSheet("test");
Row row = sheet.createRow(0);
Cell inCell = row.createCell(0);
inCell.setCellValue("01.0234500");
Cell outCell = row.createCell(1);
FormulaEvaluator fev = wb.getCreationHelper().createFormulaEvaluator();
String value = inCell.getStringCellValue();
outCell.setCellFormula("VALUE(" + value + ")");
fev.evaluateInCell(outCell);
You can use the same method to replace the contents of the original cell if that is your preference.

This worked for me
new BigDecimal(cell.getNumericCellValue()).toPlainString()

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???

After you have added all your data to the sheet, you can call autoSizeColumn(int column) on your sheet to autofit the columns to the proper size
Here is a link to the API.
See this post for more reference
Problem in fitting the excel cell size to the size of the content when using apache poi

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.

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);
}
}
}
}

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.

For Excel POI:
sheetName.autoSizeColumn(cellnum);

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 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(sheet::autoSizeColumn)

You can add this, after your loop.
for (int i = 0; i<53;i++) {
sheet.autoSizeColumn(i);
}

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.

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

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 wrap the text as well. PFB sample code:
CellStyle wrapCellStyle = new_workbook.createCellStyle();
wrapCellStyle.setWrapText(true);