Hi,
Thanks for posting your query. We reviewed your case and we have following options to handle your requirement:
1) Export your JRXMLs from the current Jaspersoft Studio 7 version and upload them to the latest version. We understand you do not want to pick this option because your files are not on a folder on disk, but rather in the DB. However, maybe there is a way for you to import/export them from/to filesystem and DB.
2) You can avoid the migration if you move to JasperReports Library Professional/commercial version. This version is not released yet but is planned to be released soon. This distribution of our software will have the ability to work with older file formats. It will also offer APIs to programatically process report template files, but this would require you to write some code to leverage such feature, although it would not be actually required, as mentioned.
3) Stay with your current version of Library and Studio.
I hope this helps.
Teodor