A couple months ago a few of us at work thought it would be worth looking into some of the newer programming languages and frameworks that have been receiving a lot of buzz. We were particularly interested in some of the productivity boosts that have been preached as a result of using these solutions. We decided to focus on the creation of a proof-of-concept (PoC) for one of our major web sites (sort of a stripped down CMS solution). The PoC consisted of two implementations, one using Groovy and Grails, and one using Ruby on Rails. On the Ruby side of things, we decided to look into JRuby, rather than the MRI or Rubinus implementations, since the majority of our development efforts rely on the JVM. Based on the success of this process, we are even open to considering these technologies as a possible replacement for ColdFusion and its assortment of frameworks that we currently use in our web tier.
I decided to move forward with Groovy and Grails in the first implementation. Its syntax seemed to be the most like Java which is what I am most comfortable with. I spent about 4 weeks learning the basics needed for Groovy and the Grails framework. From the little I’ve used it, I really like Groovy as a language. Learning Groovy was a cinch. The availability of closures, the use of builders to simplify configuration, and the emulation of formal properties using Groovy Beans are all great features. After seeing the amount of work being put into Groovy Swing integration, I can’t think why anyone would want to write a Swing UI in straight Java again; the syntax was just as simple as MXML without the markup. I am curious if any classpath conflicts would occur between dependencies in Groovy and our own projects, but I didn’t look into this any.
As far as Grails goes, I am really impressed at the work put into combining the technology stack on which the framework is based. The biggest and most notable feature I like is its tight integration with GORM. The use of GORM as the relational mapper truly makes working with the database effortless. Integration with legacy databases is fairly simple if you want to re-use your Hibernate mapping files, or if you want to do the configuration yourself in your domain classes. Because of GORM, you can approach pretty much any web application focusing solely on your object model; our shop follows this practice already as do most Java shops, so this is a big plus. On the templating side of things, I am pleased to see the work put into GSP. One of the main reasons we went with ColdFusion was because of the simplicity it provided over JSP, so GSP is a welcome attempt at change. Another feature I really like about Grails is the ability to create service classes to hook into, and expose, JEE endpoints with the utmost of ease. I didn’t get a chance to play with these, but from what I’ve seen in the plug-in section, it looks like working with JMS, SOAP, JTA, and a few other standards is ridiculously simple. Yet another feature I really enjoyed was the integration with Spring Web Flow. The scoping in Grails seems so natural; flows are very simple to construct and alleviate a lot of the hacking most developers have to put up with in the session scope. Finally, bundling an application into a WAR is provided out of the box so creating a Grails app and dropping it on your favorite JEE server is fairly effortless. From the little I got to work with the Grails framework, you can tell the team’s focus is clearly to improve Java in the web tier and they are on the right track. I know offering Spring integration is definitely a big draw for me since we use it so heavily in most of our initiatives.
Keeping in mind I worked with Grails 1.0 RC1, I did run into some difficulties with the framework. The first and biggest frustration I encountered was when working with domain classes. When I changed a domain class, while the built-in Jetty server was running, the server would attempt to reload the Spring context but just hang. As a result, I would have to take about 30s or so ever time I changed a domain class to bounce the built-in Jetty server. I’m not sure if this has been fixed since I played with it, but this really deterred me from working with Grails. One thing that I got frustrated with was what seems like a limitation in GSP. I wanted to create a view to edit a domain class which had a one-to-many relationship with another class. A pre-selected multi-select list box seemed like the perfect HTML widget to use. I was unable to find a way to automatically have GSP generate this for me. I searched the user forums, but I only found a post that said an implementation wasn’t available at that time. I didn’t search for a JSP library that may help, but maybe this could have been a viable alternative short of writing the code to render the HTML myself.
So after the Groovy and Grails experience, I dove into JRuby and Rails. Being that I scare easily at the sight of anything new, a colleague recommended Dave Thomas’ Rails book to get started; I also had other colleagues as resources to help in times of need. Since I’ve become more familiar with the Ruby syntax I must say there are some language aspects I do like. Mixins available at the language level are a lot handier than I would have thought, especially in the context of Rails. Properties and module level methods were nice to work with as well. I can definitely see where the “enough rope to hang yourself” analogy comes from however; I encountered a lot of variations on how to syntactically accomplish the same task. From a configuration standpoint, I also had to do some work to setup my environment. In the end, I had to pull down JRuby (1.03) and install the rails (1.2.6), activerecord-jdbc-adapter, and warbler gems as well as update my JDBC driver. Since JRuby is just an implementation of the Ruby language, however, I was able to use any Ruby reference, tutorial, or example I could find and had no issues.
As far as Rails goes, I was pleasantly surprised by how easy it was to get started. One of the biggest things I like about the framework is the inclusion of data migrations. You are required to interact with the database at a certain granularity but those interactions are abstracted by writing Ruby code. I’m not necessarily a fan of this granularity, but from a maintenance perspective, this is one of the best solutions I’ve encountered for managing an application’s database. I am also glad to see to see the FormOptionsHelper class. When data binding isn’t sufficient, the FormOptionsHelper class provides a lot of convenience methods to help work with select boxes. Tasks such as pre-populating a multi-select list box were extremely simple using options_from_collection_for_select. Lastly, I really liked the work done to integrate the use of REST into the framework. Working with ActiveResource seems fairly straightforward and doesn’t require as much configuration as I expected; that being said I haven’t worked much with this feature yet.
Based on my limited experience with JRuby and Rails, there were a few things of which I am wary. I haven’t looked into this much, but having two language cores available in JRuby freaks me out a bit. Without guidance or standards, I can definitely see a junior developer using Java implementations when Ruby ones are available forming a strange mixture of code. Another point to watch is the current maturity of the tools to migrate a Rails application to the JEE platform. ActiveRecord JDBC and Warbler are still under active development (although close to 1.0 releases) and it did take quite a bit of investigation to get my PoC working with our existing environment. Additionally, I don’t like ERB as a templating language. This is a personal preference, but it reminds me of PHP which I dislike for its heavy use of scriptlets; I really prefer using tag-based markup for templating. Finally, and probably the biggest thing I don’t like, is Rails’ implementation of ActiveRecord. ActiveRecord is cripplingly associated with the relational model rather than your application’s object model. A simple relationship such as belongs_to doesn’t relate to a composition relationship between a parent and child object, it relates to which tables contains the foreign key in your relational model. I designed my PoC with an object model in mind and had quite a bit of frustration, semantically speaking, trying to migrate that model into the mold for ActiveRecord. I felt like my focus was on the database for the most part and that seemed contrary to the goal of the framework.
Ok, so enough for my probably useless feedback, let me tell you what we decided to do. My personal preference lies with Groovy and Grails. The side of me that needs a solution in the immediate however, led to my choose JRuby on Rails. Let me explain. When I worked with Groovy and Grails, my learning curve wasn’t with the language, but with the framework. I found myself having lots of difficulty accomplishing tasks that I had expected to be fairly effortless. I associate a lot of these difficulties with the current state of the Grails framework. This is not meant to come off with a negative connotation, but with the perspective that Grails is the “new kid on the block” and still needs polish. When I worked with JRuby on Rails, the learning curve was with the language, not the framework. Rails met my expectations regarding the work needed to accomplish my goals (short of the ActiveRecord hoopla). Rails has the current advantage over Grails since it’s had the opportunity to be exposed to its community for 2 major iterations now. Getting an environment configured and working is a one time cost; I don’t count this again JRuby on Rails although it was easier to manage with Groovy and Grails. Additionally, running on JRuby provides us with the minimal level of Java integration that we need to re-use our existing architecture. JRuby 1.1′s focus on performance and very eminent release as well as Eclipse tooling support via RADRails are also an added plus.
So that’s the verdict from my PoC, but its not the end of my opinion. Anyone who has read this far and thinks I’m full of shit, ignore this next paragraph unless you want to flame me. I ultimately believe that Groovy and Grails will win out for the majority of users utilizing Java in the web tier. All of the arguments I have made for JRuby on Rails are based around the availability and maturity of its resources. These are arenas in which Groovy and Grails have just recently entered into competition. Groovy is quickly becoming the alternative for those in the Java community who are looking for a syntax with which they are more comfortable that brings a dynamic flare. Although it may have helped, Grails doesn’t seem to have the influence yet to cause the recent spike in popularity that Groovy has received as compared to what Rails did for Ruby. I think Java interop will also become more of an issue as people begin using languages running on the JVM. From the little I’ve seen, I really like Groovy’s approach, it feels familiar. I also think developers, like myself, are looking for re-use from the Java libraries and frameworks that we’ve relied on and with which we have experience. Grails’ tight integration with Spring, Hibernate, and other JEE standards (defacto or not) will make these approaches even simpler. It seems like since Grails explicitly chose to support the enterprise and Rails is choosing to stay out of it. I think Grails over time will have more to offer than Rails for those looking for new solutions on web that are currently using Java. Please keep in mind I’m not saying that Groovy/Grails isn’t currently ready for the enterprise (despite the FUD going around). As I understand it, many have been successful by using these technologies; I’m just saying I’m going to wait a while and see how others have been successful and learn from their examples.
In the end, I definitely think these new languages and frameworks provide a huge amount of productivity compared to how we are currently building applications for the web at the office. Tooling definitely needs some work on the Eclipse side of things, but Netbeans and IntelliJ are providing some great alternatives in the interim. I’m really looking forward to using JRuby and Rails to create our stripped down CMS application, which has recently received the green light. I’m even more excited about continuing to work with Groovy and Grails as their communities grow (and even pushing for its use in the office). Thank you to LaForge, Rocher, Nutter, Bini, and everyone else who has contributed their time and hard work into making Java on the web productive (and fun). I really see potential in the languages being built for the JVM and can’t wait to see what the future holds.
NOTE: Sorry to Jython, Django, Scala, and Lift for not including you in this PoC. For now I’ve spread my wings enough to be dangerous, and by dangerous I mean screw up enough software to retain job security.
I hope to find the time later this year to do some more exploring.