http://stackoverflow.com/questions/9...sed-encryption
Busca este texto y revisa los enlaces que tiene:
I've implemented the erickson's answer in a really simple class:
Java AES 256-bit Encryption/Decryption class
If you get the java.security.InvalidKeyException you have to install the Java Cryptography Extension (JCE) unlimited strength jurisdiction policy files:
Java 6 link
Java 7 link
Just place the jars in your {JDK HOME}\jre\lib\security