Today I read a nice post - in Portuguese - by Fábio Akita on how to manage multiple ruby versions on your machine. I've tried it once with some tool I can't even remember the name but failed miserably. But this time things look very different. The tool here is the rvm - short for Ruby Version manager - and it works just great. Let's cut to the chase and imagine that you, like me, want to run/develop/test your code on both ruby 1.

Yesterday I've done something I should do more often: Revisit some code written a while ago for our current project and make it better. Let's face it. We all write crappy code the 1st time. The difference is in what we do about it afterwards. We might decide it's good enough and keep moving, or we could (and should!) stop and refactor it! The code I revisited worked as a refactoring exercise and it's initial version is shown below: class Jphoto .

I'll be speaking at this year's Rails Summit Latin America in Sao Paulo, Brazil. It will be a good opportunity to meet some amazing people and visit friends back home! :) Overall I'll be spending 12 days in Brazil, with 2 of them dedicated to the conference. The other 10 I'll be in Rio de Janeiro visiting my family and friends. I strongly advise you to spend some time in Rio too, if at all possible.

- Overall results First off, I'd like to thank everyone who voted on this poll. With a total of 236 votes, here is the summary of the first two questions: - Are you currently working with or researching about language alternatives for the JVM? - e.g. JRuby, Scala, Groovy {% img /assets/images/scala_improvements.png %} Tooling. The majority of comment urge for better tooling and IDE support. That simple. - Others

The motivation for this post came from a couple of messages I've seen on the jruby's google group and because I think it's pretty cool to share how we tackled this problem. - A little bit of context We, as a vast amount of people out there, have legacy Java code. A lot. In our case this legacy is pretty much crucial to our business. We can't just trash it and start from scratch.

I've just watched a video from Google IO where Martin Fowler and Rebecca Parsons went through some of the aspects that involves the development of an application for the cloud - focusing on the JVM. In terms of the Google App Engine, you don't have access to a relational database, thing I found out when I first tried it. Instead you get a Big Table. Martin put out a good analogy and you can just think of it as a nested hash map.

Wanna help improve JRuby? Make sure you read this post by Charles Nutter first. There he explains how to run Ruby specs with JRuby. Start with fixing Ruby specs is a great way to get acquainted with the code. And it’s also a important task in order to make sure JRuby is the most complete and compatible ruby implementation out there. But before you get your hands dirty, it will be a lot easier if you can actually debug JRuby’s source while fixing any specs - or bugs/features for that matter.

As always I expected a good talk from Ola and once more he delivered it. But this one was different. It might have been even boring to some ruby developers since we saw a fair amount of java code in this presentation. Ola gave us a tour through the main classes that make JRuby possible with a single purpose: so we can check out the code and hack ourselves. You can download his slides here.

The rcov_plugin project is a rails plugin for rcov that adds some useful rake tasks to your application. And since I'm currently working in a JRuby project it made sense to use this plugin. The thing is, among other stuff, an rcov report from a JRuby project includes some files that shouldn't be there at all, plus you also need to change the way you call rcov as such. Thus, I thought I'd contribute these changes to the plugin and my pull request was approved this morning - just install the latest version and you should be good to go.

As many of you know the new language supported at GAE now is Java, as officially announced on their blog. As a Ruby/Rails developer you might not be interested on it but here is a reason you should be: JRuby. It was only a matter of time until we saw some people deploying JRuby on Rails apps on GAE, like Ola Bini's mini blog app. Guess that was the first one really, as he was beta testing the service in secret.

Update: Follow up link to this issue on JRuby's Jira, here As I told in my last post, it was time to give JRuby a serious try. So I took one of our rails projects at work and decided to migrate it to JRuby and see what happens. We heavily use the XML capabilities of DB2 and this was a huge problem. Every query would work just fine through the activerecord-jdbc-adapter - part of the JRuby Extras .

Most of last QCon's presentations are available for download here. Highlights to Ola Bini's on JRuby(pdf) and Randy Shoup's on eBay's architectural principles(pdf). And while we're talking about JRuby, it's impressive how it's becoming a recurrent and big subject. Fast. It had its own small space at big event like QCon and in the last Euruko in Prague, we had a presentation by the JRuby Core Developers Charles Nutter and Thomas Enebo.