Exception getException()Get any exception associated with this file transfer. If the file transfer completed successfully, this method will return
null. If the file transfer completed unsuccessfully (some exception occurred), then this method will return a non-
nullException instance that occurred.
If the the file transfer was canceled by the user, then the exception returned will be an instance of
- Exception associated with this file transfer.
nullif transfer completed successfully, non-null if transfer completed with some exception.