Skip to main content

Setting JRuby to run in 1.9.2 mode by default

JRuby comes with both 1.8.7 and 1.9.2 (currently) and the default is 1.8.7. If you want to change it you have to feed an option at the command line:

$jruby --1.9

This weekend I had to migrate a rails program that I hadn't written and the author used 1.9.2 notation so it would not run on JRuby with the default settings. So I had to add the version option with every command which gets old quick. I looked online for a way to make this automatic (and on my JRuby books) but could only found the way to do it on a Mac or Linux but all Windows references just mentioned nebulous concepts such as environmental variables and seemed to be different from which version of Windows you are using. Here is how to do it.

Windows 7:

Got to Control Panel, System.












Wine (Crossover 10):

Java 6 version 21 will run on Wine (at least on Crossover 10) and you can install JRuby on top of that. To set environmental variables you have to go to regedit and set it there manually. Follow the screen-shots below.

Find the HKEY_CURRENT_USER option on the side bar, hit the plus sign and select "Environment" from the sub-options. Set the Key to JRUBY_OPTS (don't forget the s) and the value to --1.9 (two dashes). Then go to the right pane, right click on a white space and select "New - String Value" to create a new key. Right click on the area shown in the screen-shot. Then add a New string key with the name JRUBY_OPTS and the value --1.9 per the screen-shot.






Mac OS X and Linux:

The Mac and Linux uses a command line to set the environmental variable so it can be done with one command.

$export JRUBY_OPTS=--1.9



 

This command will set the version for the session, to make it permanent add it to your .bashrc file in your home directory.




On the mac you look for the .bash_profile file in your home directory and add the same line to it.

Comments

  1. Thanks for posting, this was pretty useful.

    ReplyDelete
  2. Thanks David. This post has helped me to run Jruby in 2.0 mode on Windows.

    ReplyDelete

Post a Comment

Popular posts from this blog

Building my own home.

I've decided. I want to build my own home. There is something special about building your own things. I built a desk for my tiny room when I first moved to L.A. My room was so small that I had to sit on the bed to use the computer so I build a high desk so I could sit on the bed and work on the computer. My roommate Trentity helped me cut the ply-wood to the right side. I still have that desk. It now sits on the living room covered by a cloth hiding the surplus of costume parts my current roommate Sean uses in his creations. Learning to build and fix things continue. And the feeling of satisfaction from fixing even small things is great. So a few years ago I heard on the NPR program the Story about a couple of educators that moved to a tent in their back-yard so they could rent their house and afford to send their kids to college. They had a special type of tent called a yurt and cooked and showered in an RV they had parked next to it. I thought I could do that. Housing in Lo

Contrasting Styles of Writing: English vs. Spanish

There is interestingly enough a big difference between what's considered good writing in Spanish and English . V.S. Naipul winner of the 2001 Nobel prize for literature publish an article on writing . In it he emphasizes the use of short clear sentences and encourages the lack of adjectives and adverbs. Essentially he pushes the writer to abandon florid language and master spartan communication . This is a desired feature of English prose , where short clipped sentences are the norm and seamlessly flow into a paragraph. In English prose the paragraph is the unit the writer cares about the most. This is not the case in Spanish where whole short stories (I'm thinking this was Gabriel Garcia Marquez but maybe it was Cortázar) are written in one sentence. Something so difficult to do in English that the expert translator could best manage to encapsulate the tale in two sentences. The florid language is what is considered good writing in Spanish but unfortunately this has lead t

My Fake Resume

Inspired by the over aggrandized bio of Joseph Rakofsky I want to write my own. If you don't know who he is; Joseph Rakofsky is a lawyer who earned a mistrial for a criminal client due to his (alleged) incompetence as reported on the Washington Post . There has been quite a few commentaries on his "Streisand-house" approach of suing all the bloggers and even the Washington Post and American Bar Association for reporting his (alleged) ineptitude. ("Streisand-house" is what happened to Barbara Streisand who wanted to have a picture of her mansion removed from the internet and she sued to have it removed. Unfortunately suing requires the filing of public documents with a picture of her house. The lawsuit had the direct opposite effect it intended. Everybody now could see legally, since it was a public document, a picture of her house.) But all that internet gossip aside I'm most impressed by his resume. Here is a quote from the website: Prior to stud