In The future is now -- Java development in 2008, Andy Glover writes:
The year 2007 was full of exciting plot twists, punctuated by growing excitement about dynamic languages, the open source evolution of the JVM, and the rise of Google as a strategic contributor to the Java community. The question is, what does all that tell us about the year ahead?
And so, despite some rumors to the contrary, I would argue that Java isn't going anywhere but up in 2008. Rather than peer into a crystal ball and try to divine the future, let's reflect on the major events and trends of the past year. Taken together, they reveal all we need to know about what's ahead in 2008.
He concludes the article with:
An African proverb states that Tomorrow belongs to the people who prepare for it today. Thus, the future of Java (at least for the next year) has already been brewing for some time. The events of 2008 will largely be shaped by the JVM itself, as languages like JRuby and Groovy grow in popularity and eventually gain enterprise-wide adoption. The promise of using Java to develop consumer mobile applications also seems more accessible than it has for some time, given Google's foray with Android and Sun's with JavaFX Mobile. Most of us will also be concerned with leveraging the emerging multicore systems and looking to Java 7's
java.util.concurrentpackages for answers. Lastly, open source Java and the business model surrounding it will continue to grow.
I agree that learning about JRuby and Groovy is a good way to be prepared for the future. Reading Ola Bini's Practical JRuby on Rails Web 2.0 Projects and/or Stuart Halloway and Justin Gehtland's Rails for Java Developers seem like good ways to get started with JRuby. With Groovy, Groovy in Action has received a lot of good reviews. For Grails, it's a bit more difficult as it's evolved so quickly w/o any updated books. I like the look of Scott Davis's Groovy Recipes, but that won't be released until March.
One thing to note: just because you learn these languages and frameworks doesn't necessarily mean you'll find a new job doing them. In my experience, there's still way more Java jobs than there is Rails or Grails jobs. I sat on a Consulting Panel last night at Denver's Ruby on Rails user group (DeRailed) and this was confirmed (at least for Ruby) by the recruiters on the panel. There were three recruiters and combined they've only seen 2 Rails positions in the last 6 months.
So if you're looking for a new job, I doubt you're going to find one that allows you to leverage your new-found JRuby/Groovy skills out of the gate. However, I do believe you can leverage these tools in your existing jobs and hopefully make your development life more efficient.