Thanks for your posting and using Aspose.Cells for Java.
We were able to replicate this exception using the following code with the latest version: Aspose.Cells for Java (Latest Version).
We have logged this issue in our database. We will look into it and resolve this issue. Once the issue is resolved or we have some other update for you, we will let you know asap.
This issue has been logged as CELLSJAVA-40530.
String filePath=“F:\Shak-Data-RW\Downloads\NP 15 pages.xls”;
Workbook workbook = new Workbook(filePath);
workbook.save(filePath + “.out.pdf”, SaveFormat.PDF);