I tried to compile the JVM 9 on a Debian this weekend, just to give it a try. The openjdk's mercurial repository returned 500 HTTP-errors 9 times out of 10. After relaunching the clone command 50 times, I managed to fetch the sources. Total size of the source code with sub-projects dependencies : 1.5 GB.<p>After that you have to further download a pre-compiled JVM to bootstrap the compilation, and install further debian packages such as X11 stuff (???). I looked at the Debian package's Makefile from the package maintainers, and then I gave up.<p>The complexity, and especially the dependencies, of the JVM are outstanding. I guess some work groups are paid to work on Java, but it seems some sub-projects are staling, while some modern expected features are still not in the JVM. For example, it's difficult to see where GraalVM is in the grand scheme. Is it replacing several previous project? Is it competing with ongoing sub-projects? Will it be compatible with most projects?<p>The problem I see with Java is : if people are not paid to work or develop it, I'm not sure people would continue to support the language and the stack, given the time and specific skills you have to invest in it.<p>At that point, Java looks more like a research project than a production-ready tool.