Apache POI

I don't think that's anywhere near equivalent. That's for reading and writing Microsoft Office docs. It has no office functionality. LibreOffice has a full API, for example to run calculations on spreadsheets [1].

The goal of bringing in dependencies is so you don't have to duplicate the functionality, in this case, crafted over decades of effort.

[1] https://wiki.documentfoundation.org/Documentation/SDKGuide/C...

[dead]