Java Library written IN Java

The other day I was considering the fact that most of the Java libraries that the community uses - they all use native code. So I was thinking, - why doesn’t the community together write a rendering library, or something like that, and put it all together. So I realized that I could have an engine that has 3 components:

The rendering:
The math:
The physics:

But then again, this may take a long time to do. So I would really appreciate the community’s support for this!

Also at the same time, OpenGL is not community - based, and cannot be built upon freely.

https://github.com/RTEKGamesInc/MangoOrange