How can I encrypt files with java ?

I don't want others to see the content of my file.so,i try to encrypt the file.
but i don't know how to do .i think there may be two ways to do that .one is coding the file with some encrpytion tachniques .Another is try to add a locker to the file ,when someone try to read it ,the trigger is touched off.This trigger need you to input the password.
These are my granted think .but i don't how to do.if you know,can you please to share with me? Thank you!

The JCE is a cryptogrpahic framework for Java. There are numerous tutorials available on the web and a guide is avaiable at http://java.sun.com/j2se/1.4.2/docs/guide/security/jce/JCERefGuide.html .

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