Exuse me gys, I am a biggener in java and I would like to know
how to use the data file in java
such as taking data from the file and printing the data in new file
is there any class library carring out this task please reply to me

This link is the java API. You will need it many times in your programming studies / career. For what you are talking about take a look at the classes starting with File, in particular FileReader and FileWriter.
Hope this has given you a starting point,
darkagn

EDIT: peter_budo gives a good example of this in this thread.