Yes, Sun played with idea of putting a JVM on the Solaris kernel.
https://www.researchgate.net/publication/220938922_Writing_S...
They also created SunSPOT before RasperryPI, Arduino were even ideas, where beyond a basic layer written in native code, everything else was Java based.
Also Java is actually used as systems language in some scenarios, just not on your desktop.
When it is compiled AOT to be deployed on bare-metal scenarios such like the SDKs being sold by PTC and Aicas (just two examples, there are other companies)
https://www.ptc.com/en/products/developer-tools/perc
When it is used on Android Things to write user space drivers.
Even 16 or so years earlier in 1990, Sun played with the idea of putting a PostScript interpreter in the SunOS kernel.
Like NeWS was the Network extensible Window System, so NeFS was the Network extensible File System, or NFS 3.0.
It was actually a great idea, just a wee bit before its time, and very poorly named and positioned!
For example: If you want to make a copy of a file on the server, you can send a PostScript program that runs in the kernel and copies the file locally on the server in the kernel with ZERO context switches, instead of sending it over the net to the client, then back from the client to the server. Even if you rsh'ed the user command "cp" on the server, it would still incur context switching, but if your copy loop was running in the kernel then it didn't need to switch in and out and in and out for every block it copied.
There are more examples of why it's a great idea in the paper.
This comparison of NeWS to AJAX also applies NeFS, which is like kernel NeWS with file operations instead of a graphics library -- it also saves you lots of user/kernel context switches even if you're not doing any networking:
https://en.wikipedia.org/wiki/NeWS
>NeWS was architecturally similar to what is now called AJAX, except that NeWS coherently:
>- used PostScript code instead of JavaScript for programming.
>- used PostScript graphics instead of DHTML and CSS for rendering.
>- used PostScript data instead of XML and JSON for data representation.
It didn't go over very well because the unenlightened philistines of the time couldn't get their head around an API to the file system that wasn't compatible with creat open close read write and ioctl.
http://donhopkins.com/home/nfs3_0.pdf
Network Extensible File System Protocol Specification
1.0 Introduction
The Network Extensible File System protocol (NeFS) provides transparent remote access to shared file systems over networks. The NeFS protocol is designed to be machine, operating system, network architecture, and transport protocol independent. This document is the draft specification for the protocol. It will remain in draft form during a period of public review. Italicized comments in the document are intended to present the rationale behind elements of the design and to raise questions where there are doubts. Comments and suggestions on this draft specification are most welcome.
[...]
Example: Copy a File
Make a copy of file (foo) called (bar). Both files exist in the same directory dfh. The request starts by looking up the filehandle for the file to be copied and creates a filehandle for the copy. The loop operator executes a procedure that copies the file using 1K reads and writes. It maintains a running count of the number of bytes yet to be copied.
Love HN for comments like these.
Many thanks for the overview, NeWS had lots of great ideas, pity we got stuck with X11 on UNIX systems.
Here's some old but interesting discussion about NeFS that I saved from Comp.protocols.NFS. (they were SHOCKED I say SHOCKED!!!)
http://donhopkins.com/home/archive/NeWS/Comp.protocols.nfs.N...