Thanks for posting your concerns.
We'd like to elaborate you, what do these features mean and what is the difference between them?
1. View document in PDF Form
GroupDocs.Viewer for Java 3.x permits you to get any document in PDF form/format. For instance you have a MS Word or MS Excel document and you want to render it in/ get it in PDF format, you can achieve this using our document rendering API. Please go through this article
in order to learn how this function can be attained. Furthermore, I've attached the sample and output documents (Rendering Sample.xlsx and Wordfile.docx documents into PDF format).
2. View Document as it is (original form)
This feature allows you to get document in its original form. For example, if you get stream of any document and you want to get the original document from it. You can use getFile method.
In this way, if you have a link on your webpage like this click here to get document
and when user clicks on it, sample.docx will be downloaded in the browser. Whereas, if your browser supports viewing of such formatted documents, user can view them in browser as well just like chrome allows PDF viewing. Please go through this article
in order to seek how this function can be achieved.
Hope it clears working and meaning of both features.
If you still have any query regarding them, do let us know.