We¹re currently successfully using poi in a webapp to read from uploaded excel files.
At present we do a check on the filename extension. If xls we use HSSF and if xslx we use XSSF and this is working reasonably well. The problem we have is that some of our users are uploading files with no extension. Is there a way to determine the type of excel file that we are dealing with programmatically? I¹d appreciate any pointers as I haven¹t had a lot of luck finding anything on the web. Z.
