Why is it almost routine, whenever anyone looks for advice on this
Forum, to be advised to use things like RVM and Bundler (apparently
there is now even a JBundler).
These things may be useful for MRI Ruby (RVM certainly is) but JRuby
doesn’t need them.
As far as I can see the simplest way to use JRuby is to download the zip
file with your preferred version and extract it into the directory where
you will build your project. Then create a short shell script or batch
file that will (a) add the JRuby /bin directory to the PATH and (b) open
a terminal at the project directory.
From that point on if you add gems (the usual way with gem install XXX)
they will be stored within the project. You can create a sub-directory
for jars to keep things tidy (perhaps /lib) and include them with
Everything is within the project directory and nothing can be mixed up
with any other project.
And if you want to run a copy of your project on another PC all you have
to do is copy the project directory and all its contents. The only thing
needed on the other PC is the JVM.
I can’t understand why people spend dozens or hundreds of hours creating
something like Bundler (or JBundler) when a half dozen hours writing an
explanation of what needs to be done and how to do it would be a lot
“cheaper” in programmer-hours and more useful because then the users
would actually learn something rather than blindly following “black box”