I read a lot about opus-codec but I am not understanding how can I use that in my sample java application. Is there any .so file available for opus which can be used?If not then how?
There is currently not yet (at time of writing) any native Java library for Opus.
The Jitsi project is a Java-based VOIP and chat client which has Opus support. This is implemented by using a binary libopus library with a Java wrapper.