The code you are converting from uses the openssl library. It carries out a triple-DES encryption using an Initial Vector. The first thing you need to understand is exactly what it's doing (and preferably why).
Unfortunately the openssl documentation isn't terribly thorough (see here) ... though the O'Reilley book Network Security with OpenSSL is quite a bit better (it's a bit out of date, though).
Once you know what needs to be done, you shouldn't have much difficulty coding it in Java using the standard javax.crypto package.
