Will there be a Linux version?

I clicked download and all that happened is it downloaded a Windows .exe file. What language this coded in? Is it Java or something else (if it's Java all that's needed is a .jar file or something)? I've been playing Runescape on Linux for about 11 years now. Original RS2, RS3 (Java and NXT), and clients like OSBuddy (including OpenGL, which I currently use). It would break my heart if I had to avoid using this because of OS support, as RS has been Linux friendly from the start.