FlexNet Manager Suite will normally only import details about executable files and files with particular extensions to be used for recognizing installed executable applications. Details of .jar files are not imported, which will explain why you don't see anything about them in the UI.
With that said, there is an interesting discussion going on in the following thread with some ideas about how .jar file details may be gathered and reported on by directly querying data from the inventory database: Log4j vulnerability - info on how to scan and question about how to determine version on results. This may be an approach that can be done by folk who are comfortable working at a technical low level in the system.
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