One might hope, but they didn't. How do you tell in Java if stderr is a TTY, and if so, what its width is? How do you do an NSS passwd lookup (as in getpwnam("pjmlp") in C etc.)?
(To be fair, these could be defended, very slightly, on the grounds that Java is a cross-platform language, even though other cross-platform languages have better answers. But then I'd raise the point about Java corrupting RLIMIT_FILES for processes it starts....)
The same way you can tell in Limbo, and its authors did know one or two things about UNIX and its evolution, although this might be considered moving goalposts. :)
(To be fair, these could be defended, very slightly, on the grounds that Java is a cross-platform language, even though other cross-platform languages have better answers. But then I'd raise the point about Java corrupting RLIMIT_FILES for processes it starts....)