Sch is a pure Java implementation of SSH2. JSch allows you to connect
to an sshd server and use port forwarding, X11 forwarding, file
transfer, etc., and you can integrate its functionality into your
own Java programs. JSch is licensed under BSD style license.

- Why JSch?
Our intension in developing this stuff is to enable users of our
pure java X servers, WiredX and WeirdX, to enjoy secure X sessions.
Our efforts have mostly targeted the SSH2 protocol in relation to
X window system and X11 forwarding. Of course, we are also interested
in adding other functionality - port forward, file transfer, terminal
emulation, etc.

WWW: http://www.jcraft.com/jsch