Apache POI XSSFWorkbook setSheetOrder not sorting

Question

I'm using Apache POI (4.1.1) to modify an existing workbook. The workbook contains four sheets. I'm using the second sheet as a template by cloning it, then writing data to the new cloned sheets. It's cloned around six times or so. At the end of this process I remove the template sheet, then I try to set a sheet order to all the sheets: the existing sheets (minus the template) and then the sheets I cloned. I'm using XSSFWorkbook::setSheetOrder to do this, and I see it change the index in debug, but when my Excel file actually writes out, the sheets are not in order.

Here is the relevant code:

        // wb is an XSSFWorkbook
        wb.removeSheetAt(wb.getSheetIndex("Original Sheet 2")); // Remove the template sheet
        wb.setSheetOrder("Original Sheet 1", 0);
        for (ReportPresenter presenter : dataMap.values()) {
            String sheetTitle = makeSheetTitleFromPresenter(presenter);
            int oldIndex = wb.getSheetIndex(wb.getSheet(sheetTitle));
            wb.setSheetOrder(sheetTitle, presenter.getAnalysisNumber());
            int newIndex = wb.getSheetIndex(wb.getSheet(sheetTitle));
            System.out.println(oldIndex + " -> " + newIndex);
        }
        wb.setSheetOrder("Original Sheet 3", dataMap.size() + 1);
        wb.setSheetOrder("Original Sheet 4", dataMap.size() + 2);

I included the debug println above to show here how I know that the index is actually being changed to the order I want with the setSheetOrder method. However, when I open the Excel file that is generated by this code, my sheets all exist but they are not in the order I have specified.

I would really appreciate some ideas! Thank you.

Answer 1

Cannot reproducing that behavior. Please show a Minimal, Reproducible Example which shows that behavior.

I will provide a such which shows that it works properly:

Start with Execl.xlsx like this:

Then following code:

import java.io.FileOutputStream;
import java.io.FileInputStream;

import org.apache.poi.xssf.usermodel.*;

public class ExcelSetSheetOrder {

 public static void main(String[] args) throws Exception {

  java.util.Map<Integer, ReportPresenter> dataMap = new java.util.HashMap<Integer, ReportPresenter>();
  dataMap.put(1, new ReportPresenter("New Sheet 1", 1));
  dataMap.put(2, new ReportPresenter("New Sheet 2", 2));
  dataMap.put(3, new ReportPresenter("New Sheet 3", 3));
  dataMap.put(4, new ReportPresenter("New Sheet 4", 4));
  dataMap.put(5, new ReportPresenter("New Sheet 5", 5));
  dataMap.put(6, new ReportPresenter("New Sheet 6", 6));

  try (XSSFWorkbook workbook = new XSSFWorkbook(new FileInputStream("./Excel.xlsx"))) {

   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(1).getSheetTitle());
   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(2).getSheetTitle());
   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(3).getSheetTitle());
   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(4).getSheetTitle());
   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(5).getSheetTitle());
   workbook.cloneSheet(workbook.getSheetIndex("Original Sheet 2"), dataMap.get(6).getSheetTitle());

   workbook.removeSheetAt(workbook.getSheetIndex("Original Sheet 2")); // Remove the template sheet
   workbook.setSheetOrder("Original Sheet 1", 0);
   for (ReportPresenter presenter : dataMap.values()) {
    String sheetTitle = presenter.getSheetTitle();
    int oldIndex = workbook.getSheetIndex(workbook.getSheet(sheetTitle));
    workbook.setSheetOrder(sheetTitle, presenter.getAnalysisNumber());
    int newIndex = workbook.getSheetIndex(workbook.getSheet(sheetTitle));
    System.out.println(oldIndex + " -> " + newIndex);
   }
   workbook.setSheetOrder("Original Sheet 3", dataMap.size() + 1);
   workbook.setSheetOrder("Original Sheet 4", dataMap.size() + 2);

   String filePath = "./ExcelNew.xlsx";
   try (FileOutputStream fileOut = new FileOutputStream(filePath)) {
    workbook.write(fileOut);
   }
  }
 }

 static class ReportPresenter {
  String sheetTitle = "";
  int analysisNumber = -1;

  public ReportPresenter(String sheetTitle, int analysisNumber) {
   this.sheetTitle = sheetTitle;
   this.analysisNumber = analysisNumber;
  }

  public int getAnalysisNumber() {
   return this.analysisNumber;
  }
  public String getSheetTitle() {
   return this.sheetTitle;
  }
 }
}

prints the following on console:

axel@arichter:~/Dokumente/JAVA/poi/poi-4.1.1$ javac -Xlint:deprecation -Xlint:unchecked -cp .:./*:./lib/*:./ooxml-lib/* ExcelSetSheetOrder.java 
axel@arichter:~/Dokumente/JAVA/poi/poi-4.1.1$ java -cp .:./*:./lib/*:./ooxml-lib/* ExcelSetSheetOrder 
3 -> 1
4 -> 2
5 -> 3
6 -> 4
7 -> 5
8 -> 6

and leads to this result ExcelNew.xlsx :

Answer 2

As it turns out, I had a misunderstanding of how XSSFWorkbook::setSheetOrder works.

I was assuming (wrongly) that setting the order of a sheet would keep the sheet in that position, kind of like slotting the sheets into their index into an array. However, subsequent calls to setSheetOrder will modify the sheet order of other sheets if your latest call implicitly modifies the order in front of the sheet used in your last call.

For example, if you have sheets ordered like this:

[StaticX, StaticY, Cloned3, Cloned4, Cloned1, Cloned2] and you call setSheetOrder("Cloned3", 3)

the order becomes

[StaticX, StaticY, Cloned4, Cloned3, Cloned1, Cloned2] which is desired.

However, a subsequent call to setSheetOrder("Cloned1", 1) will now make the order

[StaticX, Cloned1, StaticY, Cloned4, Cloned3, Cloned2] which has moved Cloned3 out of position 3.

In my debug prints I was thinking it was working because I was just checking the order that the last call set, which is of course correct every time, but when I started printing out the order of all sheets after every setting of the sheet order, the problem became evident.

To fix this, I just put all my sheetnames into an array in the order I wanted them, and set the sheet order from first to last in order, which works great.

Thanks so much to Axel for providing that minimal example.