Lol, Java is an official language. I dont know of anything that isnt programmable with Java, most websites are either written in Java or a "modification" of Java, called JavaScript. If you want a example, look at YaHoo.com. Ive seen a lot of it written in Java and JavaScript.
Java isnt really made to write games with. Its the first Cross-OS (operating system) language. Making games with it isnt exactly easy lol, you have to know a fair amount of the language to do so, even more if you want to do graphix with it.
Well, i think that should cover most of it lol, any Q's and you could always ask me ^^
The only other program i know of thats similar to RPG Maker, is Game Maker, though i have never tried or even looked at it. All i know is that it exists and some(not me lol) think it better than the RPG Maker series.
@Deadly: "certain style games"? It can make anything you want according to my best knowledge... It has no boundaries, mainly coz its being updated almost every month or so(no, this doesnt mean that its a faulty language, its just that technology keeps advancing so fast that its hard to keep up :/)
Java even has its own operating system, called Solaris.
For more info, you're free to visit JavaSoft.com ^.^