NPE in SheetIterator when the workbook (2007) contains a chartsheet

[Nico Mommaerts]

Hey,

I'm reading an Excel2007 file with 2 sheets, one being a chartsheet. When I
want to get the sheetnames I get a NPE.
I couldn't find this in the buglist or the mailing list.

Example:
        OPCPackage opcPackage = OPCPackage.open(file.getAbsolutePath(),
PackageAccess.READ);
        XSSFReader xssfReader = new XSSFReader(opcPackage);

        for (SheetIterator sheetIterator = (SheetIterator)
xssfReader.getSheetsData(); sheetIterator.hasNext();) {
            sheetIterator.next();
            System.out.println(sheetIterator.getSheetName());
        }

This is the offending code in the SheetIterator class:
public InputStream next() {
            ctSheet = sheetIterator.next();

            String sheetId = ctSheet.getId();
            try {
                PackagePart sheetPkg = sheetMap.get(sheetId);
                return sheetPkg.getInputStream();
            } catch(IOException e) {
                throw new POIXMLException(e);
            }
        }

The returned PackagePart is null for a chartsheet.
I get this in 3.6 as well as in 3.7-beta3. Is this already known or is there
a workaround?