Step one :
Download required files from hear. This two file are not shifted with standalone jre download. Hear you will get two file namely :
Step Tow :
Find jre installation directory in your windows/linux machine .
And locate the path
C:\Program Files\Java\jre6\lib\security //[in case of my windows 7 machine]
Step Three :
Just past downloaded two files in located directory and overwrite previous two.
This will facilitate AES key generation up to 256 bits.
keyGenerator = KeyGenerator.getInstance("AES"); keyGenerator.init(256);
For enthusiastic readers further reference on Java Security