Using a real name and a signature are regarded as polite here.
> Wasn't able to see a bug report on this issue yet... Hope I'm not doublng
This is a problem on your system. Also, macOS issues should be reported
to R-sig-mac ... and you should give the 'at a minimum' information
requested by the posting guide.
> There seems to be little info around for what "R CMD javareconf" does but
> it has some deprecation errors seemingly.
See R CMD javareconf --help , and the R-admin manual.
> On running cmd in terminal:
> Java interpreter : /usr/bin/java
> Java version : 9
> Java home path : /Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home
> Java compiler : /usr/bin/javac
> Java headers gen.: /usr/bin/javah
> Java archive tool: /usr/bin/jar
> System Java on macOS
Try updating your R (as suggested by the posting guide): javareconf did
not detect Java 9 on macOS until the it was released recently. You are
trying to use an obsolete system installation of Java (not Oracle Java).
From the NEWS for R 3.4.2.patched (and R-devel)
• R CMD javareconf has been updated to recognize the use of a Java
9 SDK on macOS.