Apache POI Java Excel Performance for Large Spreadsheets

Question

I have a spreadsheet I\'m trying to read with POI (I have both xls and xlsx formats), but in this case, the problem is with the xls file. My spreadsheet has about 10,000 row

Answer 1

If you are using Apache POI to generate large excel file, please take note the sheet.autoSizeColumn((short) p); line because this will impact the performance.

http://stanicblog.blogspot.sg/2013/07/generate-large-excel-report-by-using.html

Answer 2

f you are using Apache POI to generate large excel file, please take note the following line :

sheet.autoSizeColumn((short) p);

Because this will degrade the performance.

Answer 3

I did also some processing with thousands of large excel files and in my opinion POI is very fast. Loading that excel files tooks also about 1 minute in Excel itself. So i would confirm that the problem lies out of POI code

Answer 4

I did some more detailed profiling and it looks like the problem is actually in code outside of POI. I just assumed this was the bottleneck, but I believe this is incorrect.

Answer 5

I would attempt to use the streaming hssf as well introduced in poi-beta3. This helped the memory issues on large spreadsheets with 1000+ columns.