You could compare the bytes you get from reading the file, but I have never used that way and I don't know how it will work.

As far as the almost identical you will need to decide the ruling.

http://java.sun.com/javase/6/docs/ap...putStream.html

http://java.sun.com/javase/6/docs/ap...redReader.html

http://java.sun.com/javase/6/docs/ap...putStream.html