Is there a tool that will replace Excel file transfer back and forth and merging?

Question

Some outdated software relies on downloading multiple Excel files, merging the contents, sending it, someone will make some changes to it far, and then send the modified Excel file back, where the next day several Excel files will be displayed loaded again and merged with it file. Is there any tool (preferably for Java or which can be used from a Java program) that will allow me to replace this old code, since saving / expanding it is a bit preferable to self-immolation?

I must add that the reason why we use Excel in general, and not the database, is because some of the reports can only be exported as Excel, and on our side some employees are convenient to use Excel formulas. Thus, we need something that they can edit as Excel, but we can do all of the above otherwise.

Update: these files do not contain images, just normal data and Excel formulas. I leave the “sending” general, because it can be easily changed. It can be FTP, via email, via a web form, etc. It doesn’t actually change the nature of the process.

Answer 1

Google Docs Sheets should be reviewed.

Answer 2

If you are looking for a library for reading and writing excel files, see http://jexcelapi.sourceforge.net/