We are trying to develop a utility which can encrypt the file into AES-128,RC2 and RC4.The encrypted file which will come as a output can be uploaded into a system which will decrypt the file.The system has a capability to detect the encryption and upload the data into the system.

The main challenge I am facing when we are getting xls or xlsx file with different encoding (UTF-16,UTF-16BE,UTF-16LE) . The system to which file(xls , xlsx ) is getting only supports the UTF-8.So we need to convert (UTF-16,UTF-16BE,UTF-16LE) to UTF-8 xls or xlsx file.

My Approach
When a xlsx or a xls file is coming is picked by utility the following steps are followed
1.Convert the xlsx or xls file to a CSV file. (We are using jxl.jar)
2. Change the encoding of this csv file.(normal method using buffered reader)
3.Convert the csv file back to xls or xlsx depending upon which format was originally uploaded.(We are using poi and jxl jars)

Can someone help respond to thread so that I can share code etc.