Introduction - If you have any usage issues, please Google them yourself
JAC (Java Asn.1 Compiler) is a tool for you if you want to
(1) parse your asn.1 file
(2) create .java classes of data types defined in your asn.1 file and
(3) do encoding/decoding of instances of your generated classes.
BER, CER and DER are all supported. Just download and import it into your eclipse workspace.