I'm working on an application which takes Excel files as inputs. These files may have some tens of columns and several hundred thousand rows. They reach 50-60mb in size on the disk. hotmail.com
I'm mainly using java 1.8 and JSF 2.0, as well as apache POI (and a bunch of other libraries which are not important now). 10.0.0.0.1
What I need to be doing is to permit the user to associate the headers to a certain expected header. For example, you expect a header called Frequency and you have an input called Freq.
What needs to happen after is that I should let the user redownload his/her input file, with the expected column names. 192.168.1.254
What I do is I recreate a blank sheet and repopulate it with the new headers and data from the old file.