Hello, I've been using POI for some time now at work and we already had many issues because POI was not able to stream. For large Excel exports (> 100k rows) we usually get OutOfMemory issues. As there was no solution to this problem we went back to plain old CSV file which at least can be streamed.
We noticed the apparition on POI 3.8 of the SXSSF workbook which permits to stream. First i'd like to know about that: Is it possible to make it stream directly to the servlet stream instead of streaming to a file? So that the user doesn't need to wait the end of the file generation before receiving data. The problem we have at work is that we work for a large car industry which still uses XLS files on many countries, not XLSX. Is it possible to stream as well the creation of XLS files? -> It seems not right? Is it possible to easily convert an XLS to an XLSX file? -> It seems possible but should be handled manually (i think) and not sure it wouldn't consume a lot of memory. For now our hardware is something like: - Server1: backoffices - Server2: preproduction - Server3 - 9: frontoffice Each server is quite powerful and running from 20 to 30 VM of 0.5Go to 1Go (one per country) For now the only solution i see, except switching to CSV, is to have a separate webapp just for Excel file creation. But it needs some developpments, and some overhead because of multitenancy, because each separate country can be considered as a tenant with a separate database, and we only want one excel webapp per tenant. Do you have any other idea? Is POI going to solve this kind of problem in the future? Thanks!
