According to several posts I\'ve found out it\'s now possible to perform CAdES using BouncyCastle but there is hardly any documentation on the topic.
For starters I want
CAdES is an extension of CMS (aka PKCS7), which is possible to do with BouncyCastle. RFC5126 contains everything needed for a CAdES signature, also, I recommend lookup info on ASN.1 since most of the parts are described in that format.
I am currently in hunt for the same answer you are looking for and found that the book Beginning Cryptography with Java by David Hook gives a lot of detailed information you might need.
Useful code could be found on "https://joinup.ec.europa.eu/"
Take a look on CAdESProfileBES.java.
Someone put the same code on Fork of the original SD - Digital Signature Service.