I can't seem to monitor unix servers in jruby (using JRuby 9.1.13.0 btw). I'm getting the following error:
mode not supported for this object: rw
org/nio4r/Selector.java:107:in `register'
...
It might be that nio4r just doesn't work with unix sockets in jruby, but I still had to ask, as they're selectable in JRuby using IO.select.