[jitsi-dev] How can I use libjitsi?

I am a student in terminal phase for the obtaining of an engineering degree
in computing. I develop a communications tool in video, audio, instant
messaging, video conference. I use Asterisk like a server, Sip protocol and
The used programming language is Java / Swing. Could you help me please:
how can I use libjitsi to develop this application. I do not know where
from to begin.

Please help.