Ah, forgot about that. It’s not really Java though. Google wanted a license for Java, but were unable to obtain one from Sun who owned it then. So it’s not actually an official implementation.
The official footprint of Java now seems tiny. It’s effectively been removed from the web by browsers. Whenever I come across it (a few academic web sites still have it) Safari makes it very hard to use. And I am exceptional in having Java installed – Apple stopped bundling it with the OS years ago.
No-one makes GUI Java apps that I know of. The only use seems to be how we use it, for command line apps. Which it’s pretty good for but there are also lots of alternatives, most of them not so dependent on a company like Oracle, who seem to be losing enthusiasm for keeping it free to use.