it is very easy if you know java io package, jdbc and string handling. you can
read data  from file  using inputstream and outputstream. then insert  into
database using standard sql queries using jdbc package.

If you are not familiar with the ".sql" package from Java. The below
web link ought to help  you out tremendously. It gives very short,
but specific examples using every package in Java.

http://www.javaalmanac.com/egs/?