Greetings, in general 40'000 rows is a very small volume of data and I would not like to suggest employing Streaming in that case. Instead, you can hold 40'000 rows in a XSSF workbook easily if you just provide enough memory. Using a XSSF workbook, you can modify the content directly as you have tried.
However, if you work with really large data of 1 Mill. rows and many columns, then the following approach will help: 1) engange the Excel Streaming Reader 2) read both files F1 and F2 simultaneously and compare row by row and cell by cell 3) based on the found difference, create a new row with new cells and write that to your result file F3 You can not modify existing cells in a SXSSFWorkbook. Best regards Andreas On Thu, 2020-02-20 at 14:01 -0700, amishad02 wrote: > I have read all previous ask question but there is no solution I found. > I need to modify excel file with large data over 40,000 rows. > Steps done in below code. > Create new file for Result > Copy file 2 for result to highlight not equal cell > Create Workbook for 2 compare excel files > Temp XSSFWorkbook > XSSF cellStyleRed as SXSSFWorkbook cannot have cellstyle color > keep 100 rows in memory, exceeding rows will be flushed to disk > compareTwoRows from both excel file not equal will change cellstyle color to > red on Result file. > Problem is with below code Result file is blank there is no content. > I understand my code is incorrect as SXSSFWorkbook is creating new sheet. > HOW CAN I update result file with change cell color?
