Yeah, Java has many built in libraries. I have currently started studying a few 3D tutorials, though I'm going to hold them off until I get some decent work done on my current projects.
Also, it appears that Java has nearly the same syntax and uses many commands similar to C/C++/Obj-C/C#. So similar that you can convert your Java code to C and compile it to work on individual platforms as native byte code. I believe that making a UI in Java on TextEdit, is about as hard as making a UI in Obj-C on TextEdit. Though that's where Netbean's graphical IDE comes in. Just drag all the buttons, windows, or text fields you want in the field and you can easily create your interface in a matter of moments.
-Gandolf