Add Digital Signatures to Excel Spreadsheets in Java

Aspose.Cells for Java

We are pleased to announce the release of Aspose.Cells for Java 17.8. This release includes many new features and enhancements along with some critical bug fixes that further improve the overall stability of the APIs. We also recommend our clients to use the powerful Aspose for Java APIs directly in their Maven Projects with simple configurations. Please check the release notes in order to get an idea about what is new and what has been fixed with this revision of Aspose.Cells for Java. Here is a look at the major features in this release.

Add Digital Signature to Excel in Java

Aspose.Cells provides the methodWorkbook.addDigitalSignature(DigitalSignatureCollection digitalSignatureCollection) that is used to add a digital signature to an already signed Excel file. The following code sample shows how to add a digital signature to Excel in Java.

Please note while adding digital signature to an already signed Excel document, if the original document is Aspose.Cells generated document, it works well. But if the original document is generated by other engines (e.g. Microsoft Excel etc.), Aspose.Cells cannot keep the file same after loading and re-saving it, this will make the original signature to be invalid.

Export Comments while Saving Excel file to HTML

When you save your Excel file into HTML, comments are not exported. However, Aspose.Cells provides this feature using the HtmlSaveOptions.IsExportComments property. If you set it true, then HTML will also display comments present in your Excel file.

Output Blank Page when there is Nothing to Print

If the sheet is empty, then Aspose.Cells will not print anything when you export the worksheet to the image. You can change this behavior by using the property ImageOrPrintOptions.OutputBlankPageWhenNothingToPrint. When you will set it true, it will print the blank page.

Disable Downlevel Revealed Comments while saving to HTML

When you save your Excel file to HTML, then Aspose.Cells reveal Downlevel Conditional Comments. These conditional comments are mostly relevant to old versions of Internet Explorer and are irrelevant to modern Web Browsers. You can read about them in detail at this link. Aspose.Cells allows you to eliminate these Downlevel Revealed Comments by setting the HtmlSaveOptions.DisableDownlevelRevealedComments property to true.

The screenshot shows the effect of this property on output Html when it is not set true.

Disable Downlevel Revealed Comments

Create Remove and Get GridCell Comments

Aspose.Cells for GridWeb supports creating, removing and getting GridCell comments. For more detail, please see this article.

Aspose.Cells for Java Resources

The resources, you may need to accomplish your tasks: