Yup, this is pure java, but I did not do the final painting of the polygons myself, just use make all my 3D vertices in world coordinates transformed onto 2d format (screen coordinates) and just used the simple java built in routines to draw them
Graphics.fillPolygon(int xPoints, int yPoints, int nPoints) method only.
So there isn't any lighting, unless I wanna go down to the drawing of individual pixels myself... which I feel that I would rather use some already well developed standards like LWJGL or JOGL.
I will be releasing source code today, go back there see if the link to the src is up.
[Edit] The link to the src is http://www.comp.nus.edu.sg/~cheefoos/src.zip
For every problem I encountered for the drawing, I did it in the simplest way which I feel is sufficient for this applet.
Things like view volume clipping, depth sorting, and even the collision detection, they're not fool-proof at all. Just able to get the job done.
Don't press P.. I haven't implement the 3rd weapon yet.. so currently it hangs the game, throwing a nullpointerException. Will implement the 3rd weapon in the next release.