The problem is: "I have a web application and I have to do something so that user can upload excel sheet data to application and also user should be able to download data to excel sheet". I have to do this in java.
Is the problem just the file upload and download (both easy enough to accomplish), or does the file have to be read upon upload, or to be generated when it's dowloaded?
If the latter, then either POI or jExcelAPi (both linked at AccessingFileFormats) can be used.
Problem is the data contained in the excel sheet should be uploaded to database (oracle 9 i) and on download data from same database can be downloaded in same excel format.
so What i undersatnd is first I will have to FTP my excel sheet to server and then after reading each cell I will be saving data to database...Please correct me if I am wrong. But at same time I also want excel sheet to be temporarily saved on server... I mean once data is saved excel sheet should be deleted..
Whether you want to open the Excel sheet and read its contents is up to your requirements. You can just take the whole thing and stuff in into a BLOB field in the database, or store it on the server file system.
Whether FTP is the best way to get the file to the server also depends on your circumstances, about which we know nothing.
I am successfully able to upload excel sheet to server and read it. But now I want to incorporate download functionalty. In this I would like to take a predefined excel template and write data from database to it. Can you please help me out with this.