Installing Your Own JRuby to Use With the NetBeans IDE
By divas on Feb 09, 2009
The Ruby support for NetBeans includes a bundled JRuby installation. This is great for quickly getting started with the IDE, but I recommend that you download and install your own version of JRuby and use that one instead. There are a few reasons for doing so, one of which is that the next time you install a NetBeans version, you will get a new bundled JRuby installation, most likely a different version. If you have added gems to the old bundled JRuby, you will have to reinstall those gems to the new bundled JRuby.
Another reason is when you want to work with more recent JRuby version. For this reason alone, it is good to learn how to install JRuby and register it with the IDE. Below are the steps that I do to add a JRuby installation.
First download JRuby from the JRuby site and install it by following the Getting Started instructions.
TIP: If you are downloading the 6RC1 version, after you unpack it, rename the directory from jruby-1.1.6RC1 to jruby-1.1.6. For some reason, The GlassFish app server barfs on the RC1 in the path name.
Put JRuby's bin in your environment path. I remember reading some recommendation that if you have both Ruby and JRuby, put JRuby after Ruby in the path. Because I switch out JRuby versions often, I created a JRUBY environment variable that points to the bin directory of the JRuby that I am working with, and I added the JRUBY environment variable to my path. To test it, I type jruby -v on the command line.
Now you can register your new JRuby installation with the NetBeans IDE. Choose Tools > Ruby Platforms from the main menu. Choose Add Platform, and navigate to and select the JRuby executable in the bin directory. If you are on Windows, this is jruby.bat. Click Open.
This step is optional, and I don't suggest it if you are new to Ruby and installing gems. I get tired of having to install the same gems over and over every time I upgrade JRuby, so I create a separate repository (outside of the installation folder) for the gems. If you want to do this, click the Browse button to the right of the Gem Home text box, type the path to your gem repository, and click Open. (If you don't have one yet, use the New Folder button in the dialog box to create it, such as some-ruby-repo-path/jrubygemrepo. When you click Open, it will ask if you want to set up your repository there, click OK.)
Next click the Add button to the right of the Gem Path text box and add the repository to the gem path.
You will need the debugger gems. Follow the instructions on the NetBeans Ruby Debugger wiki page. Make sure you get the correct versions -- the ones noted on the wiki page. If you opted for a separate gems repository in the previous step, then add --install-dir your-repo-path to the gem install commands.
Next, I install Rails. You can do this from the command line, or from the IDE's Ruby Gems Manager, which is available from the main menu. When you open the Ruby Gems manager, click the Settings tab and select Fetch All Versions so that you have a choice of which version to download. Then click the New Gems tab and click Reload Gems. Select Rails and click Install. You will be asked to select a version. If you want to follow the 6.5 tutorials, be sure to install Rails 2.1.2 or 2.1.0 because you need Rails 2.1.\* for the tutorials. Version 2.1.1 is not compatible with JRuby.
Some other gems you might want to install right away are jruby-openssl, Active Record JDBC Adapter, and the JDBC adapters for the databases that you use. See Using Database Servers With JRuby for more information about the JDBC adapters.
Hopefully, this is complete enough to get you going. Please add comments if you have suggestions or steps to add.