[furtivefelon]

Like i said....
Java is programming language for Sun Microsystems servers with SPARC Architexture and Sun OS. If he wants to build a SUN computer, there ya go. (Though that's more than likely not going to happen.)
Linux was a good suggestion. Most distrebutions are FREE!

mmm.. i don't think so, java runs on Java Virtual Machine, which more likely than not is built on c/c++, if you want to start a OS from scratch, there is no way you can use java to communicate directly with cpu, it won't even boot..

Since you've listed three languages, prob those are the ones you've heard somewhere (java is very hyped, c++ is touted as backwards compared to java, and there are alot of old basic books), when you look at the kernel of, for example, linux, you won't find a single piece of c++/basic/java code, everything is written in c..