Graeme Rocher's Blog

The main portal for Sky television has relaunched written in Grails. Sky, also known as British Sky Broadcasting or BSkyB, employs 17000 people in the UK and operates the largest satellite network in the UK.

The site receives a million+ hits per day and joins all the other subsites also written in Grails:
Congrats to the Sky team!

Update 07/10: Couple of new things have arison since this was posted. Firstly, Sky actually employ 17000 people not 11000. Seems the Google sample data I obtained was out of date.

Also Glenn Saqui has a nice write-up on the architecture of Sky.com on Marc's Blog. Altogether the 4 subsites listed above receive over 110 million hits per month and run on a cluster of web layer machines and 2 db machines. Checkout the aforementioned link for more info.

Our busy community of plugin developers have been at it again and now there is a brand new plugin for Grails that adds support for the Terracotta data grid. It was always possible to do this with a bit of manual configuration, but now the plugin automates things nicely using a few new Grails command line scripts.

This is one of the really great things about Grails and Groovy, because Groovy classes are just standard Java classes it is possible to integrate Groovy or Grails applications with any existing Java infrastructure, including data grids like Terracotta and Coherence. Awesome stuff.

Wow, the Groovy/Grails community is really getting it together. First we had the launch of grailscrowd.com, which is a social networking site for Groovy/Grails people to connect with other Groovy/Grails people. The site is built on Grails and its only been up for a few days but aldready over 600 people registered. If you haven't done so do so! The source code for GrailsCrowd is also availabe at Github

Not to be outdown, however, Glen Smith has launched the Groovy Awards ! A site dedicated to nominating the best contributors and to the Groovy / Grails community. Awards up for grabs include Groovy / Grails t-shirts and other goodies. Check it out.

On my front, I know I have been rather inactive posting. Books are really all consuming beasts. I have given a go to twittering now and again about what I'm writing about, although I'm still not sure I "get" twitter.

I'll be giving a talk on the state of Grails at the London Groovy+Grails user group meeting on the 31st of July. Skills Matter are hosting it as usual, be sure to sign-up here.

Apologies for not posting as frequently recently, I've been hard at work on the second edition of "The Definitive Guide to Grails" and also working on feature development for Grails 1.1 (we now have JSP tag library support in GSP and massive improvements to the plug-in system).

Nevertheless, on to the topic of this post, we (G2One Inc - The Groovy/Grails company) have launched our public Groovy & Grails training programme in the US. Announcing this exciting news is Jeff Brown, our main guy in the US, who has this to say:

"Our training events are a fantastic experience. G2One are the folks who lead and sustain the development of both Groovy and Grails. No one understands the technology better than the people who build it. G2One training events give developers an opportunity to spend several days with a technology expert covering everything from fundamentals to advanced language and framework features.

The sessions include a perfect mix of lecture and reinforcing lab work. That hands on approach is a great way for developers to internalize the details. There is no better way to quickly get a team up and running with the technology."

Check it out!

Brian Guan, one of the pioneers of Grails use within LinkedIn, has started a blog series about their experiences with Grails. The first post presents the slides the LinkedIn guys presented at the recent Groovy/Grails meetup at JavaOne. It makes for an interested read so check it out!

We've just released Grails 1.0.3, which includes 230 issues resolutions and improvements since the last release. The release notes go through the full details, including outlining some of the new features like enum support and interactive mode.

Grails has come a long way, since the release of 1.0 Grails has been downloaded over 186000 times averaging out to around 50000 times per month. That puts it on par or not far behind some of the biggest open source projects like Spring, Hibernate and Struts in terms of downloads.

The most exciting thing for me though is the plug-in community with over 70 plug-ins in the repository some of the new ones include Axis 2 support, Java2D with GraphicsBuilder and profiling (contributed by one of the biggest Grails users LinkedIn) and debugging plug-ins. Awesome stuff.

Now I'm shifting my focus to the second edition of the book, and feature development for Grails 1.1.

G2One, Inc. and Callista Enterprise AB have announced a partnership to support Advanced Groovy and Grails training in Scandinavia.

Göteborg 2008-09-08
Stockholm 2008-09-15
Malmö 2008-09-22

The 3 day comprehensive course covers details from intro to advanced for both the Groovy language and the Grails framework. The course description may be found here.

As with all G2One training events, students will receive a free 12 month license for IntelliJ IDEA. IDEA's JetGroovy brings fantastic support for both Groovy and Grails to the IDE.

Please contact us at training at g2one dot com with any training related inquiries.

Although I wasn't able to make JavaOne due to my bought of pneumonia, Guillaume did an excellent job of delivering my presentations and then did everyone a favour by posting them online! Here we go for those who haven't seen them yet:

We've just launched a re-write of the Grails.org site in Grails. Previously the site was powered by Confluence (the Atlassian wiki), now in the spirit of eating ones own dog food it is a fully Grails powered site.

Ever since the Seam guys launched seamframework.org powered by Seam I felt something had to be done, before we could look them in the face again ;-)

Now its there and its more than a simple page turner, but a full featured wiki engine including versioning, diff'ing etc. and the source code is available at Codehaus. Enjoy!

As I write this JavaOne 08 is being wrapped up and I am horizontal in bed. I somehow managed to get pleurisy and pneumonia a few days before the event so missed it completely.

Luckily, the awesome Guillaume Laforge delivered my talks on Groovy and Grails instead of me, but sorry to those who were expecting to see me there, health comes first in this case.

It seems to have been another successful conference from what I could infer from the twitter feed and various blog postings. Was nice to hear Groovy in Action was 3rd and The Definitive Guide to Grails 6th of the best seller list after day 1.

On that topic of the books, being bed bound for a couple of weeks has given me the chance (when I'm not sleeping and feeling too ill) to spend some time planning and writing the second edition of the "The Definitive Guide..".

I'm co-authoring with Scott Davis, so the book should be bigger badder and more impressive this time. Target release date is the end of the year. Lets hope the codene doesn't make my ramblings to incoherent!

For those of you interested, Grails applications deploy and execute on SpringSource's new Application Platform without any issues. I have updated the Grails deployment page to that effect.

Great to hear that Grails won second prize at the JAX innovation awards, Guillaume was there to accept the award as I was away on annual leave in Thailand.

Would have been nice to win first prize, but since Groovy won last year I guess that would be too much to expect :-)

There is a remarkable amount of innovation going on within the Grails community itself, just in the past week or so we've had new releases of the Selenium plug-in, the JSecurity plug-in, a JAWR plug-in, an OpenID plug-in and the new simple Authentication Plug-in.

All contributed by our awesome user community. Amazing.

The news that Ext-JS has, from one release to the next, changed from a modified LGPL to a GPL based license nearly made me fall off my chair. There have been many poor judged, and ill advised decisions made by software companies over the last few years, but this has got to be up there with the stupidist I've seen and I'm not even personally an Ext-JS user.

What they have effectively done is built up a community, taking full advantage of the open source model by accepting user contributions and patches and then turned around and kicked their own community up the backside. It is projects like Ext-JS that give open source a bad name. How can a company have faith in open source if the people behind it can't even decide how to license the thing?

When you start off in the software business you have to very early on decide whether you are an open source company or whether you are a commercial software company. If you choose the former then you need to choose an appropriate license. For platforms the GPL license can make a lot of sense (think Linux and Java) to prevent forks, force contributions etc. although I'm still not a big fan of it.

On the otherhand for libraries or frameworks only a few licenses make sense (Apache 2.0, MIT, BSD and to a lesser extent LGPL). With Grails we went for Apache 2.0 as one of the most liberal licenses out there. Once you've decided on the license as an open source company your job is the grow the community by attracting users who put faith in your product and the fact that its licensed in a liberal way. Those users would not come in the first place if you had a restrictive license.

By choosing the open source route you have made a decision as a company to promote the community driven approach. Of course this doesn't stop you from releasing a commercial version, you could dual license it as Ext-JS have done for those who want the comfortable feeling of paying for something. You cannot however, have it both ways you are either an open source company or you are not. Ext-JS seem to be stuck in 2 minds as to whether they really are an open source company, it is this indecisiveness that is going to see their community go elsewhere.

It is not like they're unique either, the Ajax framework space is super competitive and they've just dropped the ball and given their competitors a big advantage. My personally prediction on this one is that they'll lose a lot of users, probably to Yahoo UI and jQuery UI or possibly Dojo. Something else will soon come along to fill their space and soon they will have lost their competitive advantage, their users and all those license renewals.

Sky (commercially known as BSkyB), who are the biggest satellite broadcaster in the UK and largely owned by News Corporation (Rupert Murdoch et al), have re-launched their Sky showbiz news portal, powered by Grails.

The site was put together by energizedwork, a consulting firm in the UK, well done guys!

This represents one of the largest, commercial public facing Grails applications (that we at G2One Inc are able to talk about at least ;-) out there at the moment with traffic in the region of 186 million page views a month. Its great to see so many huge companies taking the leap to Grails, long may it continue!

This year, along with Guillaume, I will be presenting 2 talks at JavaOne 08 on Groovy and Grails:

As well as a single talk at Monday's CommunityOne 08 event:
See you there!

Checkout my new Groovy Zone article Using Groovy & BeanBuilder for Spring + Hibernate Integration Testing

There is a new dynamic language shootout featured on InfoQ where Groovy comes out on top as the JVM language of choice for a variety of reasons and one of the reasons cited was that it is a near superset of Java. Queue the comments from the Ola Bini brigade that:

"If you're going to use Groovy the same way you use Java, there is absolutely no gain. Just a performance hit."

However, this sadly is missing the point. Sure, if you write Groovy like Java you get no real benefit, but it provides that migration and, crucially, learning path onto a Groovier way.

Learning a programming language is for the most part trivial and can be achieved in a few days. Learning the libraries is what takes the time. Groovy shares the same Java APIs as standard Java, you know things that you know and love like java.io.File, java.lang.String etc.?

The real difference comes in what it adds to these standard libraries through the GDK. For example great stuff like this:

myFile.eachLine { println it }

def contents = new URL("http://google.com").text

def list = ['a','c','b']
list = list.collect { it.toUpperCase() }.sort()

def text = "Hello World"
text = text - "World"
println text // prints "Hello "
println text[0..-3] // prints "Hell"

Once you learn the "new way" combined with meta-programming capabilities that Groovy has on offer you'll never look back.

Scott Davis came up with a great quote to describe this at the recent 2GX: Groovy/Grails Experience:

"Groovy is Java AND Groovy is not Java at the same time"

In other words, you get the best of both worlds.

Sven is back with his Grails podcast, now a fortnightly event, and even better Glen Smith, the brilliant ozzie behind Gravl and Groovyblogs (2 great Grails sample applications), has joined him!

Check it out.

The Atlassian guys (creators of JIRA, Confluence etc.) are using Grails for some of their projects and have written a nice article on how to setup Grails, with the Acegi plugin, and Atlassian's single sign-on (SSO) solution Crowd. Nice work.

The nice chaps at eWeek turned up at the 2GX:Groovy/Grails Experience and interviewed me and Scott from aboutGroovy on the subject of Groovy and Grails and its relationship to Java. Check it out

At 2GX - The Groovy/Grails Experience, I did a presentation on empowering Spring with Groovy DSLs which demonstrated Grails' Spring BeanBuilder in action.

The demo showed how Spring and Hibernate can be dynamically configured at runtime using BeanBuilder and then interacted with via the Groovy shell. I promised a few I would make it available so here it is.

You'll need Groovy 1.5 and Gant setup before you start then just type:

gant start

Enjoy.

So, I'm back from the 2GX - The Groovy/Grails Experience which was yet another event, brilliantly put together by Jay Zimmerman and the No Fluff crew. The good news is, if you missed out there is another one in the fall/autumn months in San Jose, CA.

The attendance was excellent for such a focused conference with close to 200 people in total all buzzing about Groovy & Grails. I delivered my "State of Grails" keynote on the Thursday evening which went into some analysis of where we are since the release of Grails 1.0 from a growth perspective, but also from a technology perspective.

I wasn't planning to, but a few people at the conference asked me to post my slides to help persuade managers etc. of the viability of Grails, not just from a technical perspective, but from a growth and community perspective. So if you're in the same position, check out my slides, the following is a summary of the contents.

When we released Grails 1.0, Codehaus' bandwith usage went up by a staggering 40gb. The downloads have been in the 10s of thousands since the release and luckily Contegix, the kind folks who host Codehaus, have freed up some extra bandwith for the servers.

The mailing list traffic on the Grails user mailing list has gone through the roof, averaging close to 140 messages a day in January and looking the same for Feb:


The traffic is contributing to make Grails one of the most vibrant communities around anyone one Java web framework according to Nabble:

Further evidence of the growing community is the Grails plug-in eco-system where Grails now has no less than 47 user contributed plug-ins in the plug-in repository representing nearly 2 million lines of user contributed code:


Blog traffic is also on the up, a year ago the blog traffic for Grails was merely a blip on the horizon (all probably posted by me ;-). Now according to technorati people are talking about Grails, a lot:

Clearly, we still have a long way to go to make Grails as hugely popular as things like Spring and Hibernate, but we're heading in the right direction which is great news.

Last time there was a major Groovy/Grails conference, we promised to get Grails 1.0 out in time for the conference, somehow we slipped a few months ;-)


This time there is no such slippage and the 2G - Groovy/Grails Experience is coming to Reston, Virginia on the 21-23 of Feb! Organised by the No Fluff crowd, it features an amazing amount of great Groovy & Grails talks from some great speakers (other than me of course ;-).

I'll be doing 3 talks on various aspects of Grails and can't wait, its going to be a great event. See you there!

We've put the finishing touches on Grails 1.0 and its out. Time to celebrate with some sleep.. enjoy!

There is a report that is being pushed around comments on blog posts with the aim of spreading FUD. The report can be found here:

http://www.huxili.com/index.php?cat=reports&id=ID000188

It is entitled "Groovy and JRuby: Enterprise Ready?" and its conclusion is that Groovy is not due to "memory leaks". The report is complete nonsense of course, and it put together by someone who doesn't understand the different language idioms.

The report provides no code examples, further bringing to question its validity, however it states that Groovy runs out of memory when running these steps:
I'm going to have a go at guessing the Groovy code they used. I can bet it goes something like this:

shell = new GroovyShell()
while(true) {
shell.evaluate("x = 100")
sleep(2000)
System.gc()
}

So what is the problem with this code? And why would it result in a memory leak? The answer is that each GroovyShell instance has an internal class loader. Groovy is a compiled language. Even little scripts like this are compiled into classes so over time the class loader just gets bigger and bigger. The solution? Here we go:

while(true) {
new GroovyShell().evaluate("x = 100")
sleep(2000)
}

So what this does is allow the GroovyShell (and its class loader) to be garbage collected by the JVM. When the class loader is garbage collected so are the classes loaded within it. JRuby of course doesn't have this problem as its interpreted.

Judging whether a language is "enterprise-ready" without knowing the language idioms and basing it on a 4 line script is to be honest quite ridiculous, so remember beware of silly "official" looking reports without verifying the facts for yourself.

Something interesting has been happening in the blogosphere over the last few days. It seemed to all kick-off with Rick Hightowers post on Why Syntax Matters. It seems a mini-backlash is brewing against the Ruby hype.

Rick feels (and this is his opinion) that Sun should ditch JRuby and support Groovy because the syntax and migration path is so much easier for Java developers. He and several commenters on his blog, feel that Ruby is too different to Java. The post was features on JavaLobby and InfoQ.

This is of course the main reason I was sold about Groovy as it eliminates the context switching between languages as they are so similar, but a blog post that got me thinking the most was Cedric's entitled I'm not Tired of Java Yet. And you know what? I agree with him.

Unlike Ola Bini (JRuby committer) who is repeatedly questioning Java, I love Java and still believe it is a great language for many common tasks. Its just not great for everything. In the past Java was seen as "the one language to rule them all". Now as alternative languages like Groovy start to mature, its about picking the right language to solve the problem at hand and that tool is often Java.

Things like processing strings, doing really dynamic stuff and heavy manipulating of collections can get painful in Java. However, its death is highly, highly exaggerated. One of the reasons I believe so strongly in Groovy and Grails is that it is not about ditching Java or the Java platform, it's about embracing it.

Groovy supports true polygot programming when combined with Java thanks to the seamless way they integrate with one another. I, and most Groovy programmers, still love programming in Java and have no plans to ditch it anytime soon. Use each language when it makes sense. It is about using the best tool for the job.

Grails 1.0-RC4 is out. Download here. In three weeks 1.0 final will be with us, fun times :-)