I have an 07 excel with 62000 records(10+ columns). I read it in with 15 secs and almost 300mb memory used,and then write it back to file .But after over 4~5 minutes,i lost my patient.. i seems to be endless. I found POI can deal with excel with almost 20000 records in a reasonable time cost.
Is there a way to improve read & write performance? i didnt do any thing for logging(log4j for configured,and i suppose the POI disable the logging be default) Or to say,is there any stream api for me to modify some specified cells(then commit these changes) WITHOUT loading all records in and then saving them as a whole. PS: As an alternative, i found the excel can output content as an XML file(including excel 2002,i dont know if 2007 still compatible),which can be opened ,modified and saved by excel later(with all formats & records saved :) ). So can i use RandomAccessFile with indexed element position to change the file(just the part of the file not the whole) more efficiently(is there any tools,of or not of POI, to parse the file)? Any suggestion appreciated O(∩_∩)O
