Planet Acceleo

Laurent Goubet: User interface improvements in Acceleo 3.1

noreply@blogger.com (Laurent Goubet) — Mon, 16 Aug 2010 08:10:00 +0000

Acceleo 3.1.0 is due June, 22 2011 along with Eclipse Indigo ... seems far, but not as far away as we sometimes hope for with all the features we'd like to add in our products.

Because of this, we've already started implementing some of the (many) improvements we'd like to make in the Acceleo editor : support for template, query and module documentation, support for more markers to display feedback to the user (information, warning, "overriding" link...), support for tasks in the template (TODO, FIXME, ...), improvement of the oultine, feedback on the non-printable characters that will be generated ...

Stephane Begaudeau is reponsible for most of these first additions, you can find a list, detailed explanations and screenshots in this great post.

Most of these improvements have already found their way in the source code and will be available in the 3.1M1 release of Acceleo tomorrow, care to test? Or are there features you would like to see in the Acceleo module editor? Don't hesitate to take part in the discussions, raise bugs or provide feedback on either bugzilla or forum :).

Stéphane Bégaudeau: User interface improvements in Acceleo 3.1

Mon, 16 Aug 2010 08:03:00 +0000

Three weeks ago, I started to work on some new features for the next release of Acceleo next year. Jonathan and Laurent told me to use Acceleo as a regular user and to find any feature that would be missing. Quickly I had some ideas to improve Acceleo and I started to work on some of them.

In Acceleo 3, we have a system to report errors to the user with red markers in the editor. Starting with Acceleo 3.1 we will have a support for new markers like warnings or informations such as the green arrow to quickly see if a template overrides another template (if you click on the green arrow, we will open the overridden template in another editor).

We will also have a support for two new tags in comments “@TODO” and “@FIXME”. Those two new tags will create new tasks in the tasks view just like with the JDT.

We will have a new block for the documentation “[** … /]” because the comment block “[comment … /]” is a bit too long. With that documentation block, we will have a new refactoring process which will allow us to quickly generate a documentation block by typing Alt+Shift+J on a query, a template, a macro or a module. Just like in the JDT, it will create a documentation block with “@param” tags for each parameters of the selected template or query.

The documentation will be saved in the “emtl” files (Acceleo modules when compiled) and this documentation will be available when the cursor of your mouse is over an element.

Or during the autocompletion.

We will also have an improved outline view with new icons in order to see the visibility of an element and new actions in order to sort elements inside the outline view or to hide non public elements, templates or queries. All imports will be put under an “import declaration” node in the outline view.

Finally we will have a support for deprecated elements with the “@deprecated” tag in documentation blocks. It will create a warning on the deprecated element (a query, a template, a macro, or a module) and if used on a module, all elements of the module will be considered as deprecated.

And the last, but definitely not the least. The AcceleoEditor will have an action to show all the invisible characters that will be generated by Acceleo. If you look carefully, you will see that after the end of the header of the “[for (attribute : EAttribute | e.eAttributes)]” the new line will not generate a new line in the generated file.

You can see most of those improvements in this screenshot and when they will be available (they won’t be all in Acceleo 3.1 M1) don’t hesitate to send us your feedback in the forum or in the bugzilla.

Cédric Brun: Eclipse Helios - a whole year of goodness

noreply@blogger.com (Cédric Brun) — Tue, 27 Jul 2010 13:09:00 +0000

Eclipse Helios is a release, but it's also a complete development cycle in a global and distributed team of commiters. Since I choose 3 features I especially liked in Helios this kept bugging me : what is Helios to me ?

Helios will have its place in my memory, not the bits themselves but good things we had as a community.

1 - The Acceleo Community joins Eclipse.org and starts by using black magic to build bits

It's just the begining of this move but so far it went pretty well :)

2 - Eclipse Summit Europe is the best Eclipse conference to meet friends

3- The dreaded diamonds of the Simultaneous Release are still haunting my dreams...

4- Our friend Hudson is now serving way more projects, but not always happily.

5 - The Foundation keeps moving things forward

6 - EMF Compare rocked at Eclipse Con 2010

Last but not least, this Helios cycle was filled with more interactions with end-users and adopters leading to nice enhancements in Eclipse as a whole, thanks for your help !

Stéphane Bouchet: worlcupForecast : final results

noreply@blogger.com (Stéphane Bouchet) — Mon, 19 Jul 2010 11:29:08 +0000

Hi,

If you played with our special forecast application, you can see here the results.

Thanks for the 71 people who used this application, feel free to comment/ report enhancements/bugs to the project.

See you in next competition ! football ? basketball ? hockey ? ;)

Jonathan Musset: Spain are world champions and Fanny wins the Eclipse forecasts

jonathan.musset@obeo.fr (Jonathan Musset) — Mon, 12 Jul 2010 09:02:00 +0000

España Gana la Copa!

Spain victory is the fruit of a lot of work. Andres Iniesta was the man of the match for the final game. He is to be congratulated for that. However, I would like to highlight another person today, the woman who wins the Eclipse EEF world cup forecasts. She isn't an Eclipse commiter but she lives with an active Eclipse modeling commiter. This is something that needs considering, isn't it? ;) Thanks for all those who share our life, like you... I'm surprised that you have more points than me ;) I also give you thanks for showing us that women know soccer as much as men, and above all that an Eclipse RCP application is also usable by a non-computer scientist ;)

Thanks to the EEF and the Acceleo teams that created this nice application in few days. EEF deserves to be adopted.

This is the final ranking table of the Eclipse World Cup forecasts 2010.

Congratulations to Laurent and Florian for finishing second and third! And finally, congratulations to Nathalie who won the Obeo version of the game. A revolution is in process!

Jonathan Musset: Eclipse WC 2010 Final round - 7 persons can win now

jonathan.musset@obeo.fr (Jonathan Musset) — Thu, 08 Jul 2010 12:49:00 +0000

You can win 16 points this week-end for the final round of the world cup forecats. Here is the ranking table. I will come back with the final results on monday 12.

Have fun! Don't forget the Eclipse DemoCamp in Nantes today!

Freddy Allilaire: Eclipse DemoCamp in Nantes this week

noreply@blogger.com (Freddy Allilaire) — Tue, 06 Jul 2010 18:28:09 +0000

Don't forget this Thursday if you're closed to Nantes to attend to our Eclipse DemoCamp.

Here we have the program:
18:00 - 18:10: Welcome
18:10 - 18:35: Modisco, by Gabriel Barbier, Mia-Software
18:35 - 19:00: WTP with Glassfish, by Laurent Ruaud and Evariste Konkolé, Serli
19:00 - 19:25: Acceleo, by Stéphane Bégaudeau, Obeo
19:25 - 19:50: Eclipse SOA, by INRIA
19:50 - 20:15: ATL in the AtlanMod Model Management Architecture, by Hugo Bruneliere, EMN/INRIA
20:15 - 20h45: GMF Showcases, by Etienne Juliot, Obeo
20:45 - 21h00: Open discussion

Our goal: few slides, lots of demos!

If you want to attend, please use the wiki page: http://wiki.eclipse.org/Eclipse_DemoCamps_Helios_2010/Nantes

See you on Thursday!

William Piers: How to improve your forecasts using ATL

Mon, 05 Jul 2010 14:26:51 +0000

In order to extend the Eclipse World Cup 2010 application with other modeling tools, I made a simple ATL transformation which helps football ignorants like me to improve their results…

The ATL refining mode allow to modify an EMF resource in-place, by defining a minimal set of transformation rules. It is also possible to query informations from an input model.

So I created the ATL module below, which updates a given forecast model - mine - by copying forecasts from another player - better than me .

The following screenshot shows my updated model, improved with the new results:

Anyway, I didn’t have to use that cheat as my initial forecasts were not bad at all !

Laurent Delaigue: Acceleo 3 and properties

noreply@blogger.com (Laurent Delaigue) — Fri, 02 Jul 2010 13:43:00 +0000

Since I'm often brought to develop acceleo generators, I often had to design my templates so that they can be easily parameterized by users.
This is important since by doing so, acceleo modules are flexible enough to fit my users needs and (hopefully) I don't have to update modules too often.
Of course, you need to carefully design your templates to achieve this modularity. But for simple needs, simple solutions are the best.
Acceleo natively supports the use of properties files which is an efficient and simple way to parameterize generation module: Properties are generally simple to understand and users can use them easily.
Well, Acceleo 3 is out, and of course properties are still supported. I just wanted to point out something I stumble upon just recently: Properties files are now accessed via the java ResourceBundle mechanism. And consequently, they need to be in the classpath in order to be accessed at runtime.
So, as a module developer, you'll place your default properties files (those you provide with your modules in order to have a sensible default behavior) in a package of your module project.
Well, don't forget to check that this package is exported at runtime, otherwise your properties won't be accessible when you run your generations!

You probably already know how to do it but just in case: open the META-INF/MANIFEST.MF file, and in the Runtime tab just add the package(s) that contain your properties files.
And since you need to do this also for your entry point templates, it may be a good idea to place default properties files in the same package as the entry point template files?

Laurent Goubet: Using code generation under ClearCase

noreply@blogger.com (Laurent Goubet) — Wed, 30 Jun 2010 08:25:00 +0000

Those of you that know ClearCase also know that it requires the user to check out the file he wishes to edit before any editing can be done; kind of trying to edit a read-only file : you need to remove the read-only flag before anything else. Of course, this doesn't fit well with code generation tools such as Acceleo since the aim of such tools is to edit (or create) a number of files at once.

Until now that is :). Acceleo can now be used in conjunction with ClearCase or other pessimist-locking Version Control Systems (VCS). How does it work?

You might have noticed the "getGenerationStrategy()" method of the Java class we generate for your main mtl files; this is the method that matters for us. You simply need to change it from its default "return super.getGenerationStrategy()" to "return new WorkspaceAwareStrategy()" and you're done! Acceleo will now prompt the users of your generators to check out the files before attempting to modify them.

Two things to note :

You must change the javadoc of "getGenerationStrategy()" so that it doesn't contain "@generated" anymore : delete this tag, change it to "@not-generated", change it to "@generated NOT"... just don't leave this tag as-is or the Acceleo builder will override your change.
You cannot use this strategy in standalone mode, its goal is to integrate with the Eclipse workspace and its team providers.

The use case with ClearCase or pessimist locking VCSs is obvious, but you might realize that there is more to it that just these. You could be trying to regenerate a file that you set as read only, a file under SVN that requires a lock...

For example, with SVN you can set the property "svn:needs-lock" on a file to prevent any edition without prior locking. If you attempt to regenerate a file with such a property set with Acceleo, here is what you will get :

"java.io.FileNotFoundException: [...]\Library.java (Access denied)"

Pretty mean, huh? If you make use of the WorskpaceAwareStrategy though, you will get this instead :

All you have to do is to tick off the files for which you wish to take the lock. Files you do not check will not be locked for edition.

Jonathan Musset: Women on top of the Eclipse World Cup Forecasts

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 30 Jun 2010 08:10:00 +0000

I'm glad to see that a woman is on the top of the Eclipse World Cup forecasts table. Will Fanny win the competition? Who said that women don't know anything about soccer? Nathalie is 10th. Loredana is 21th. Each day, Lynn is better and better. She's now 25th in the table... There are 70 players in the game and the identified women are on the top of the results table. Well done!

It's not too late to come into the game! For the final phase, the score is multiplied by 2! So you keep a chance.

Freddy Allilaire: Acceleo 3.0.0 is released!

noreply@blogger.com (Freddy Allilaire) — Tue, 29 Jun 2010 17:08:18 +0000

Acceleo 3.0 has just been released and it comes with compatibility with Eclipse 3.4, 3.5 and the latest 3.6 versions. Acceleo 3.0 is a pragmatic implementation of the OMG Model-to-text specification. It supports the developer with most of the features that can be expected from a top quality code generator IDE: simple syntax, efficient code generation, advanced tooling, features on par with the JDT... Acceleo also has a unique tooling around example-based design of code generators with all the pragmatism we had with the 2.x stream.

Acceleo can be downloaded and installed in a number of ways. If you have an existing Eclipse installation and simply wish to install Acceleo in it, installing through the update site is the easiest way. If you'd rather install a new Eclipse with Acceleo, you may want to take a look at the facilities provided by the amalgamation project. Amalgamation is the project that leads the creation of the modeling bundle, it has an easy one click discover and install wizard. Thanks to it you could also easily install also ATL 3.1 (the model-to-model transformation language in Eclipse), EEF (a way to improve the EMF model creation), EMF Compare 1.1 and many other modeling components.

Acceleo 3.1 will be released in June 2011 with the Eclipse Indigo release train. We also planned several corrective versions for the 2.x maintenance stream: a 2.7.1 version will be released this year and a 2.8 version in 2011. Meanwhile, the Acceleo team is investigating towards Eclipse 4 (e4) compatibility. All the links and information to download and install Acceleo are available from here: http://www.eclipse.org/acceleo/download/

Note that examples are available from the menu right-click => New => Examples => Acceleo Plug-ins.

Do not hesitate to give feedback through the mailing-lists, the bug-tracker or the web forum, a Wiki is available to ease the collaboration and the gathering of tips and tricks.
Support information: http://www.eclipse.org/acceleo/support/
Developers information: http://www.eclipse.org/acceleo/developers/

Thanks to all the developers and contributors involved in this release!

Cédric Brun: 3 Good Reasons to use the Helios Modeling Package

noreply@blogger.com (Cédric Brun) — Mon, 28 Jun 2010 12:31:00 +0000

Now that the entire world noticed that I don't know even one thing about soccer and I'm even trying to cheat, I should get back in sharing what I understand instead of those silly forecasts.

Helios has been out for a little while now, the mediatic storm is pretty much gone and it's a good time for me to have a look back.

This year one of my goal was : "I want to transform the Modeling Package in a product which I would use myself". I've been using it quite extensively lately and I'm pretty happy with the results, the Galileo package is far from being usable but the Helios version is just great :)

Why ? a few reasons...

1. because it's including hidden EMF goodness !

EMF generates code... which is good as any code you don't need to write means less bugs. But sometimes you don't even want to see that code !

If so, you're lucky, there is a specific filter for your workspace !

And the integration goes even further, code you manually changed is highlighted with different colors !

Oh, and you can compare and merge any kind of emf model, starting from the Ecore ones.

2. It provides Class diagram support

As a developper you always ends up needing some kind of graphical support for your communication, a class like diagram is well known by others, the modeling package includes support for Ecore thanks to the EcoreTools project.

And you even have specific views to browse your design hierarchy or usages.

While I'm at it, if you're interested in contributing to this project which is highly popular, you should really get in touch with Ed ! We're looking for fresh people to reboot this project, it's not as active as it deserves to be !

3. It's an SDK

As the modeling project provides a lot of high quality frameworks, you often need to have access to their source and as such it's one of the few packages providing SDK's.

All those reasons are making the modeling package the best one to get started with any modeling task but also any RCP development planning to leverage those great frameworks.

Oh yes, that should make this package a nice starter for e4 too :

post scriptum : 4. It's easily extensible

Of course the modeling community is way more active than that, I would strongly encourage you to have a small click on this button and have a try on the latest hot contributions which were not part of the Helios release the Agent Modeling Platform :

And the Papyrus UML modeler

And now it's time for you to download this package !

Jonathan Musset: Don't forget the Eclipse Modeling webinar

jonathan.musset@obeo.fr (Jonathan Musset) — Mon, 28 Jun 2010 12:11:00 +0000

Don't forget the Modeling webinar today at 3:30pm UTC!

The Eclipse Modeling Project is one of the most active projects within the Eclipse community. Ed Merks will give a quick overview of the Modeling projects in Helios and Sebastian Zarnekow will show Xtext. Cedric Brun will mainly talk about Acceleo and he will demo what Obeo has done for this Helios release.

Cédric Brun: Forecasts Comparison For The World !

noreply@blogger.com (Cédric Brun) — Mon, 28 Jun 2010 08:04:00 +0000

I have to admit I know nothing about soccer. Yes I'm a french guy, but I know nothing about soccer. That said I'm not against having a few beers in front of this broadcasted green field and I'm always in when its about having fun with a small game leveraging Eclipse technologies.

Obviously I played with the EEF based rich client for the forecasts, and from the moment the source code has been made available I started hacking the code.

The forecasts, matchs and results are all kept in a model accessible through an http uri, and as EMF rule them all, find them, bring them all and in the darkness bind them, you can leverage any Eclipse Modeling component to hack something quite easily.

That's what I did with Compare.

I extended the EMF editor adding a specific action, "Compare with / Player with Best Rank"

This action allows you to compare your own forecasts with the best ones, and then merge your own forcast with the best player one (Noooo, that's not cheating ! )

And here is the user interface you get for free*, with a pure semantic comparison :

* you have to depend on EMF Compare though...

Here is the logic needed to launch the comparison :

I had to use a few tricks, I had to provide a specific match engine enforcing the match of two players, otherwise the Compare component stop matching the forecasts from the beginning as the players are differents.

That's all for today, If I can free more time for this hack I'll provide a diff extension to change the score delta representation to a more meaningfull one, so far it's left as an exercise for the reader ;)

Jonathan Musset: How to migrate from Acceleo 2 to Acceleo 3?

jonathan.musset@obeo.fr (Jonathan Musset) — Fri, 25 Jun 2010 11:59:00 +0000

Acceleo 3.0 has just been released and we have a lot of questions about how to migrate from Acceleo 2.x to Acceleo 3.x? Acceleo 3 has some differences with Acceleo 2, especially for the new syntax elements based on the Model-to-text OMG standard.

The question is : How to create the 3.x '.mtl' file from the 2.x '.mt' file?

The tooling will initialize the migration process... Just right click on the Acceleo 2.x project.

We know that the migration can't be perfect, because the MTL standard is statically typed. Sometimes you need human understanding to provide the right context and get the right equivalence. You will probably have to change the way you organize your code generators. We are confident that Acceleo 2.x users will move easily to Acceleo 3.0.

Don't worry, the Acceleo Team will continue to maintain the 2.x syntax of Acceleo. However, the new major versions and the new features will take place on Eclipse.org.

There aren't a lot of differences between the old version of acceleo and the new one. It's not so long to migrate from a syntax to another, but you should do that only if you have at least one day free. Note that it can be a little bit more for big code generation modules. Acceleo 3.0 comes with an equivalence documentation.

I hope that it will be useful...

Yvan Lussaud: How to create an Acceleo 2.x generator for composed metamodels

noreply@blogger.com (yvan) — Fri, 25 Jun 2010 01:56:53 +0000

Imagine you have a metamodel that reference other metamodels and you want to create a generator for this metamodel. Let's take an example :

The first metamodel contains an EClass named Object that have a reference package of type EPackage. That create a reference to the ECore metamodel.

First we have to create a template for the first metamodel :

%
metamodel http://www.obeo.fr/first

import manymetamodels.ecore
%>

%script type="first.Object" name="default" file="test.txt"%>
Object %name%> :

%package.default%>

Then we need to create the template manymetamodels.ecore.mt :

%
metamodel http://www.eclipse.org/emf/2002/Ecore
%>

%script type="ecore.EPackage" name="default"%>
EPackage %name%>.

And that's all. So you just need to create at least one template per metamodel and then inport them according to the way you navigate your metamodels.

Jonathan Musset: Acceleo 3.0 is out and Modeling webinar

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 23 Jun 2010 21:56:00 +0000

I'm really proud to announce that Acceleo 3.0 is out. It comes with Eclipse 3.6. Acceleo 3.0 combines nice tooling, simple syntax and efficient code generation with all the pragmatism we had with the 2.x stream.

As you probably know, Eclipse Helios is out! Obeo was greatly involved in this release. Note that there will be an Eclipse Modeling Webinar today (June 24 at 7pm CEST). I'll talk about the new features we have added this year.

Wanted : 70 players for the EEF Eclipse World Cup forecasts! 3 players more and it's done. I'm really glad to be on the top 10, but the first guy is flying... Don't miss the final phase, the score will be multiplied by 2! It's easy to come into the game. Come at any time! See the rules.

Obeo was involved in several projects of the Helios simultaneous release :

Acceleo 3.0 is a pragmatic implementation of the OMG Model-to-text specification. It supports the developper with most of the features that can be expected from a top quality code generator IDE: simple syntax, efficient code generation, advanced tooling, features on par with the JDT... Acceleo also has a unique tooling around example-based design of code generators.

ATL 3.1 is definitively THE model-to-model transformation language in Eclipse.

EEF is another way to improve the EMF model creation and it aims to improve the EMF.Edit and EMF.Editor JET code generators.

Amalgamation is the project that leads the creation of the modeling bundle, it has an easy one click discover and install wizard.

EMF Compare 1.1 mainly brings performances enhancements : ID based matching and heuristic based matching have been enhanced by a 10 factor. EMF Compare has now better support for fragmented model during the comparison.

SCA Tools provides a set of tools for the Service Component Architecture (SCA) set of standards. The 2.1 release brings compatibility with the OASIS specifications. The SCA Designer has been updated to work with Tuscany 2.x...

Stéphane Bouchet: Helios is Here !

noreply@blogger.com (Stéphane Bouchet) — Wed, 23 Jun 2010 22:00:01 +0000

Hi all,

I am proud to announce that Helios is shipped in time this year !

you can find it here :

www.eclipse.org/helios

EEF is also shipped with the modeling package :
http://www.eclipse.org/downloads/packages/

Want the update site ? no problem, it is here :

http://download.eclipse.org/modeling/emft/eef/updates/releases/

Finally, if you want to download the release version of EEF ( 0.8.0 ), it is here :

http://www.eclipse.org/modeling/emft/downloads/index.php?project=eef

I hope this year again eclipse simultaneous release will provide you the best tools for developing your applications !

Goulwen Le Fur: Eclipse Wordlcup : Bye Bye France, Hello source code !

noreply@blogger.com (Goulwen Le Fur) — Fri, 18 Jun 2010 12:31:00 +0000

Very sad day for french people, French team is probably out of the competition, thanks to Nicolas, Sidney and ... of course Raymond. Anyway, Here is the current rating in the Eclipse community :

Came from the end of ranking ldelaigue lead now the game. lredor is second, arichard third and Jens fourth. Finally fmaillet is always in top 5.

Sorry for Jonathan and Cédric who are now ranked 8th and 10th of the game. More information on : Forecast ranking.

I've just added the source code of the Eclipse Worldcup Forecast application on the Eclipse CVS. You can find it in the test directory of the eef project. Here is a PSF file.

Feel free to create you're own extension for the Eclipse WorldcupForecast Application ;)

Cédric Brun: Eclipse Modeling Survey results

noreply@blogger.com (Cédric Brun) — Fri, 18 Jun 2010 08:50:00 +0000

The survey has been going on for more than one week now and the trends are only enforcing themselves. Let's summarize it:

First, the audience represents many non-commiters (2/3) though the commiters are still quite represented. That's quite consistent with what I was expecting, the survey was published on the planet, some newsgroups and through twitter and as such targeting commiter or adopters following quite closely what's happening in Eclipse Modeling.

Concerning the package size, we're right now at 250MB, it looks like it's mostly ok but being a bit smaller would still be nice.

As the package is an SDK we could probably drop most of the dupplicated javadoc in the plugins.

This one is interesting, it's something we're hearing and hearing again at each Eclipse conference, users do want more documentation, moreover best practices are hard to reveal through the wiki, newsgroup and online help jungle.

There is probably something to do here but, hey, there is an EMF Book already, an Eclipse Modeling one and everybody can contribute on the wiki, so why isn't this urgent need covered yet ?

It might be because:

People are not even aware of these books or books are old fashioned now : all content should be on the web !
It's so hard to understand what each project is providing that one really needs some Modeling Guide.
As a user you always want doc even if you won't ever read it, it just gives you the confidence that the technology is not going to vanish in a glimpse.
[ ] ----- any opinion expressed through the comments

It's even more disturbing when ...

yes, most people would be willing to give time to make this happen. We might need to do something here, maybe crowdsourcing the doc would do the trick... What is pretty sure is I wouldn't like it if Eclipse Modeling commiters spent half of their time documenting : we should make it easier for the adopters to contribute back.

And yes, writting doc and books takes a huge amount of time !

I asked another related question in the survey about "examples". In fact examples are way easier to provide and in my opinion are more valuable in most cases. And when you look at it, each project is already building its own examples, but these examples cannot be composed in some way. Just like Toast is a best practices application for OSGi, we would need a modeling one.

At its beginning the Amalgam project was providing some; yet since these examples were not part of their target Eclipse project (EMF examples in EMF, ATL examples in ATL) they were not maintained correctly. As a result they are not reflecting the "state of the art" of Eclipse Modeling anymore... Maybe for the next release !

I'm done for the strong trendes, others questions like "Having on the shelf design and generation tools" or "Domain focused UI instead of component focused one" were quite uncertain.

A few more ideas or questions have been given through this survey,

It will take another blog post to describe those.

Thanks again for your feedback !

Jonathan Musset: My 2 cents HTML export for the WC 2010 application

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 16 Jun 2010 04:30:00 +0000

I would like to go further with the Eclipse World Cup 2010 application, to help skeptical people to believe in modeling technologies. The EEF team created an RCP 'forecasts' game. Yersterday, someone said that exporting the results in HTML could improve this game. No sooner said than done.

The RCP application comes with a metamodel project : 'fr.obeo.dsl.worldcupforecast'.

Here is a short description of how to make a simple HTML generator with Acceleo, based on this 'forecasts' metamodel.

It is recommended to use a bottom-up approach when developing generators; Acceleo eases this process by allowing you to initialize the content of a generation module with an HTML example, and offering specific actions to transform these examples (static text) in dynamic OCL expressions.

Let's create the 'results.html' example file which contains an image and a single row line.

We create the code generation project with the new HTML code generation file.

The main template is initialized with the example content. It is based on the 'forecasts' metamodel.

We would like to create a row line for each player, starting from the best to the least score. Thus, we create a 'for' statement to iterate over the players.

Finally, we run the coge generator on the forecasts model. It's done!

Note that you can directly access the online model in your launcher.

Here are the files : the results page, the Acceleo project, the MTL file.

Goulwen Le Fur: Eclipse Worldcup : First results

noreply@blogger.com (Goulwen Le Fur) — Mon, 14 Jun 2010 07:45:00 +0000

3 days of world cup, we can do a first check of the game results :

lredor and Cedric lead the game with 18 points. After, there is SMonnier, Jonathan and fmaillet with 17 points. Well played !

It's not too late to start playing if you want to join us in the game. To play, just download the application :

windows windows64 linux linux64 macosx macosx64

And add a new player. You're 18 points late but it remains 224 points to win !!

To finish, let me remind you the process to validate your forecasts :

Fill out your forecast in the application
Save the modification
Then use the menu "World Cup Forecasts > Commit" to send your datas

If you not save before commit or you not commit, the default score (0-0) we be validate and use to compute your score !

Let's play !

Jonathan Musset: WC 2010 powered by EEF and Acceleo - Results and Rating

jonathan.musset@obeo.fr (Jonathan Musset) — Sat, 12 Jun 2010 06:42:00 +0000

The first day is complete and results are online. Get the results with the menu "World Cup Results and Rating".

I'm glad to be in the first part of the Rating view ;-)

This post is also a reminder. Goulwen validates the 'forecast of the day' at 6am UTC. It's easy to come into the game. Come at any time! See the rules.

Stéphane Bouchet: EEF Final almost here

noreply@blogger.com (Stéphane Bouchet) — Fri, 11 Jun 2010 11:29:10 +0000

hi people,

Helios is almost here, just 2 weeks to wait !

We had some hard times during all the RC release process, but we succeed to provide the final bits of EEF.

If you want to test it now, and see a sample of what you can creates with EMF and EEF, check out our great sample :

http://wiki.eclipse.org/EEF_Sample_World_Cup_Forecasts

Go play ! :)

Laurent Goubet: Package with URI '*' not found

noreply@blogger.com (Laurent Goubet) — Fri, 11 Jun 2010 09:08:00 +0000

I believe most of the users of EMF (developers or adopters alike) have seen this message at least once; and most probably wondered what was going on :).

This error message indicates that the package which NsURI is '*' hasn't been registered in the Package registry. Most of the time, that means you either a) launched your program standalone and didn't register the package correctly or b) you haven't installed the plug-in that provides that metamodel.

With Acceleo, encountering this exception is even more likely than normal, as the launch configuration for our generations allow for both standalone or plug-in generations. Selecting standalone without registering the needed package will inevitably lead to this error.

Solving it is easy : it is a matter of registering the needed packages (and, optionally, resource factories). How is it done? Here is the most classic example with UML :

Package with uri 'http://www.eclipse.org/uml2/2.1.0/UML' not found.

What do I need to do for my UML model to be loadable :

EPackage.Registry.INSTANCE.put(UMLPackage.eNS_URI, UMLPackage.eINSTANCE);
Resource.Factory.Registry.INSTANCE.getExtensionToFactoryMap().put(UMLResource.FILE_EXTENSION, UMLResource.Factory.INSTANCE);

The same goes for every metamodel you might need, simply change UMLPackage by XxxPackage according to your metamodel. The Resource Factory is mandatory for UML, but your metamodel might not need one; simply ignore this line if you don't have a custom factory.

You need these two lines to be before the point where your model is loaded. For Acceleo, this is done in the generated Java launcher : simply change the implementation of the registerPackages and registerResourceFactories method to add these needed lines.

Jonathan Musset: Last Call : Now boarding for the Eclipse World Cup 2010!

jonathan.musset@obeo.fr (Jonathan Musset) — Fri, 11 Jun 2010 07:58:00 +0000

A bit of sweetness during the final Helios release build...

Want to play to the Eclipse World Cup 2010? Want to believe in modeling technologies?

Download it!

windows windows64 linux linux64 macosx macosx64

Goulwen posted the rules yersterday.

Exceptionally today (june 11th), you can play until the beginning of the first match!

Freddy Allilaire: Eclipse DemoCamp in Nantes

noreply@blogger.com (Freddy Allilaire) — Thu, 10 Jun 2010 19:31:48 +0000

Obeo and INRIA organize an Eclipse DemoCamp at Nantes on the 8th of July: http://wiki.eclipse.org/Eclipse_DemoCamps_Helios_2010/Nantes

Don't be afraid, we looked at the world cup agenda and there will be no game on this day! So you could attend quietly and maybe take a break about soccer for few hours.

However don't miss the first Eclipse World cup experience where I hope lot of people will join us (Go! Go! Go France!). If you're interested, take a look to the post made by Goulwen.

For the DemoCamp, we have started to work on the agenda and already several interesting demos will be presented: Acceleo by Obeo, MoDisco by Mia-software, WTP by Serli and more to come.

If you want to propose a demo or simply attend, please sign up on the wiki.

See you in Nantes!

Goulwen Le Fur: Share the Worldcup experience with the Eclipse Community !

noreply@blogger.com (Goulwen Le Fur) — Thu, 10 Jun 2010 09:43:00 +0000

Dear Eclipse community, we want you!

The World cup 2010 starts tomorrow and as most of the french companies (and maybe worldwide) it's time for us to use our internal forecast game to see who will be the best soccer expert!
Most of the companies use an excel sheet to do it and others more "organised" developped a dedicated web service.

But as Obeo guys are Eclipse lovers, this year we created a new RCP application for this world cup event based on several Eclipse modeling components!!! This is an EEF sample application made in three days so it's not perfect yet !

Other people could say that it will be a good and cheap way to test our products (EEF and Acceleo) ... yeah yeah but we did it also for fun. So, you soccer lovers join us! We are looking for more beta testers so the whole Eclipse community is invited to use it and of course to have fun with this experience.

Want to play with us? Want to support your favourite team? The RCP application are available here :

windows windows64 linux linux64 macosx macosx64

How to use it? A short tutorial is on the wiki.

One main rule:
- Your forecast for the 'game of the day' should be committed at 06:00AM (UTC) (link timeanddate).

Exceptionally tomorrow (june 11th), you can play until the beginning of the first match !

For more information, you can consult the Game FAQ.

A few words to conclude:

- It's free, no registration and easy to use (only 3 menus to create and commit your forecasts)

- If you find a bug don't hesitate to report it, this game was built in 3 days thanks to EEF, Acceleo and others modeling components. Don't forget your are also a beta-tester!
- The application will evolve during the world cup by using other modeling tools. Feel free to make an extension and contribute it!
- Source code will be accessible very shortly.

I hope you will enjoy it and let's get the game started!

Go! go France!

Cédric Brun: Eclipse Modeling Package Survey

noreply@blogger.com (Cédric Brun) — Thu, 10 Jun 2010 06:49:00 +0000

I've been quiet in the planet lately, it doesn't mean I've been inactive, quite the contrary in fact, just like all the other commiters I've spent the last few weeks polishing the Eclipse Modeling Helios release. (As a sidenote, I'm giving more update from here --> )

And now the final bits are almost here ! More info about what's new in the Modeling Package soon, but you might have already seen that we have a pretty good feedback :) .

Helios is almost public now, we're already wondering what shape Eclipse Indigo will have, and to do so I'd like to have your opinion. I compiled a tiny survey, 6 questions you can fill in seconds.

I'f you're interested in Modeling in General, and Eclipse Modeling in particular, please spend the next seconds filling this survey.

the survey is embedded in the post or accessible here

William Piers: New ATL homepage

Wed, 09 Jun 2010 08:58:36 +0000

The ATL homepage now makes use of the template provided by Heiko Behrens

Here is the new appearance:

I hope this will make ATL resources lookup easier !

Jonathan Musset: Two billion years of software evolution

jonathan.musset@obeo.fr (Jonathan Musset) — Tue, 08 Jun 2010 19:46:00 +0000

The Acceleo planet, the Modeling solar system, the Eclipse galaxy, and the software development universe...

The only conclusion that could be derived from a universe where everything moves away from everything else is that the universe constantly expands.

Today, more than 400 000 objects roam the solar system. The stars, planets and galaxies are in constant motion. The gravitational force acting on these celestial bodies, attracting them to each other, leads to collisions. 65 millions years ago, the impact of an asteroid on Earth has caused mass extinction of living species such as dinosaurs. In two billion years, scientists predict that our galaxy will be struck by Andromeda to form a single galaxy. Related to the origins and evolution of the universe, cosmic shocks created in the past affects the present and shape the future. The Dinosaur Extinction has probably cleared the way for us. Thus, we can also consider a collision as the beginning of something else...

Image courtesy of NASA/JPL-Caltech License

I posted this because it sounds like Eclipse plug-ins development and software evolution... Sometimes, you want to blow everything up, to go further... But, it's not easy to do...

The JDT has been re-written several times in ten years, isn't it? I think that the Eclipse XText version is really more cool than the old one. E4 will probably be a revolutionary development platform... What an exciting challenge to rewrite everything without losing the best of what you have already done? We've tried to do our best for the Acceleo MTL mutation. Now, thanks to the team, the new Acceleo version seems to be on the road... Thanks for all the positive feedbacks we have received about the collision between the Acceleo planet and the MTL celestial object. Where does MTL come from? the OMG galaxy!

I can't imagine how Eclipse could be in two billion years... It would be an ordered bloody mess, like the universe ;-)

Laurent Goubet: New Acceleo homepage

noreply@blogger.com (Laurent Goubet) — Tue, 08 Jun 2010 14:21:00 +0000

The Acceleo homepage now makes use of the template provided by Heiko Behrens.

You've seen it with MoDisco, you've seen it with Xtext, it's now our turn to change skin :).

This also makes use of the changes brought to the CSS by Fred Madiot.

Thanks to both of them !

Jonathan Musset: How an Android file could become a code generation template in few clicks?

jonathan.musset@obeo.fr (Jonathan Musset) — Mon, 07 Jun 2010 15:11:00 +0000

Let's take a simple Android metamodel with different kinds of Widgets, like Text, Spinner, Button...

Acceleo provides a way to customize quickly your Android code generator, and manage the different code generation alternatives. With the For/If menu item, you can apply a specific treatment to each kind of Widgets.

In the Java file which contains Android widgets declarations, select them and then right-click and run: Source > As For/If (Alt+Shift+F).

Each kind of Widget is isolated as a new code generation alternative.

Then fill the appropriate kind of Widget in each condition (This is the link between the metamodel concept and the textual alternative to produce for this concept).

Leave just one TextField declaration and delete the other ones. Complete it by changing the static name of Widgets with a dynamic Acceleo expression by using the Quick replacement tool.

Repeat for the other files. The Alt+Shift+F feature is more useful the second time you use it because it tries to fill automatically the alternative condition.

Acceleo 3.0 comes with an Android Tutorial. This is meant to give beginners a tutorial to get them started with defining their own code generators... and advanced users a way to discover some of Acceleo 3.0 features.

I have shown this feature at the Eclipse modeling runaway 2010 and some of you asked me to have more details...

I hope it will be useful for you.

William Piers: ATL Presentations Slides

Fri, 04 Jun 2010 12:59:05 +0000

Now ATL presentations are available on slideshare. Below are the EclipseCon 2008 & 2009 tutorials:

http://www.slideshare.net/wpiers/modelt-to-model-transformation-withatl

http://www.slideshare.net/wpiers/model-refactoring-with-atl

And a short presentation of the ATL Industrialization project given during the mtATL2009 workshop:

http://www.slideshare.net/wpiers/atl-industrialization

Jonathan Musset: 1-minute fully-functional example for ATL and Acceleo

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 02 Jun 2010 11:45:00 +0000

This message will help you to install and use ATL and Acceleo in 2 minutes or if you need to make a quick demo for your client or for your boss... Don't waste your time! Use the Modeling discovery UI of the Amalgamation project.

Amalgamation Note :

The Eclipse Modeling Package is a base and sound platform one can rely on for development tasks leveraging the modeling technologies. The Package is focusing on EMF and its complementary frameworks and tools : we call that the "base platform". That said the modeling community is way more diverse than that and provides complete IDE's for dedicated langages. Those are provided through the discovery UI.

Here is the easiest way to install and try the modeling technologies like ATL and Acceleo, by downloading the Amalgamation bundle :

Download the last EPP modeling bundle

The final release (June 23) will be available at http://www.eclipse.org/downloads

Use the modeling discovery button to install ATL and Acceleo

Examples are available for these technologies in the right-click menus New > Examples > Acceleo Plug-ins and New > Examples > ATL

Now, your workspace contains the new examples...

I will come back with some little information about the interoperability between these 2 technologies...

Coming soon...

Laurent Goubet: What's new in Acceleo 3.0?

noreply@blogger.com (Laurent Goubet) — Tue, 01 Jun 2010 14:15:00 +0000

Acceleo 3.0 is on its way out. It is currently accessible in its third Release Candidate (RC3) version. The complete list of improvements and bug fixes that have been implemented in this version since the last stable release (version 0.8.1, see my previous post for explanation on this branch's version numbering) is humongous; following is the list of the most important ones. I may be succinct on the description of some of these, but you can get a full explanation of all of them in the Acceleo documentation, namely the User Guide. Be warned though, this will be a huge post :).

Compatibility and upgrading

Acceleo 3.0 is compatible with the three latest releases of Eclipse; Eclipse 3.4 (Ganymede), Eclipse 3.5 (Galileo) and Eclipse 3.6 (Helios). However, there are some limitations to this compatibility we maintain due to the changes that were implemented in OCL since then. For one, Acceleo modules that compile in Helios may or may not compile in Galileo and Ganymede (this will depend on the OCL features you make use of). However, Acceleo modules that compile in a given version will always compile in the subsequent Eclipse releases. Likewise, a module that has been compiled in Helios may be launched in Ganymede regardless of whether it would compile or not in that version, as our runtime shouldn't suffer from OCL breakages and improvements. All information about the compatibility will be maintained on the wiki.
We provide migration facilities for those of you that own Acceleo 2 templates. Specifically, we allow for the automatic migration of Acceleo 2 generation projects to Acceleo 3 projects. The automatic migration takes care of everything that could possibly be automated, leaving for you to fix no more than the Acceleo 2 features that don't have an identified mapping to Acceleo 3, or those few features that require a human hand to convert intelligently. The team is at your disposal for help if there still remains things you don't know how to convert to Acceleo 3 on the usual communication channels : the M2T newsgroup, mails, comments on this blog...

Tooling improvements

New views have been introduced to help you on several aspects of the generation cycles : module definition, launching, debugging. I'll detail each of these views one after the other.

First of all, the Result view allows you to get feedback on the traceability information we could retrieve during the evaluation of your modules. As long as this view has been opened, Acceleo will record every bit of information it can to synchronize your generated text with the generation module and source model. Ever wondered why such or such portion of text has been generated one way or another? What part of your generation module has generated the name of such or such method? From which element of your model has been generated such or such import? This is the view you can use to retrieve these pieces of information.
Next comes the Overrides view, which can be used to easily create templates or modules overriding other that are present in your instance of Eclipse. It will display every single module located either in your installed plug-ins or your workspace. All of these can be browsed down to the template level and a check box allows you to select those you wish to override. Once selected, you simply have to use the content assistant in the Acceleo Editor (CTRL+SPACE by default) and validate selected overrides for all of the overriding templates to be added to your module.
Last but not least, the Generation Patterns view has been introduced to help you implement behavior for an interface/class and all (or a subset of) its subtypes. For example, let's say you wish to implement a template named javaName which will generate the name of any classifier. This template will need some default behavior for interfaces and specific behavior for some classifiers. Open the Generation Patterns view, tick [template] for all selected types in its top part, and all of the types you wish to generate a template for in its bottom part. Once done, the content assist in the Acceleo editor will give you the choice [template] for all selected types which you just have to choose in order to generate all of the templates you asked for. Now that you no longer risk forgetting one or more subtypes, it is left to your discretion to implement the behavior for each of them.
Acceleo now provides a built-in profiler that can be used to keep track of evaluations and identify (and, hopefully, fix) bottlenecks in your generation process. The profiler is accessible through a right click on the module which execution you need to profile and the menu item Profile As => Acceleo Application.
The Acceleo debugger now provides you with the list of available variables at a given point in the evaluation process, along with the values of these variables for a given stack frame. Moreover, the displayed stack frames now represent Acceleo module element corresponding to your current expression stack. As for the previous release, debugging templates only requires you to set breakpoints in the Acceleo modules as you would usually with Eclipse : open an editor, double click in the left margin on the line you wish the breakpoint to be set, and launch the generation through the menu Debug As => Launch Acceleo Application.
Whenever possible, the warnings and errors Acceleo logs when an evaluation fails now sport the expression stack (with the lines they're at in the module files) instead of a stack trace corresponding to the Java code that was being executed at the time. This will allow for way easier debugging that ever before.

Editor Improvements

Apart from the performance improvements and minor bug fixes, the Acceleo module editor now provides refactoring actions and quick fixes.

First of all, you can now use the “usual” shortcut ALT+SHIFT+R to rename either modules, templates, queries, variables, ... in a coherent manner. This very same action can be accessed from right-clicking and selecting Refactor => Rename. The interface will allow you to preview the changes before validating them.
Portions of the module elements can be extracted as new templates through right-clicking and selecting Refactor => Extract Template (or simply using the shortcut ALT+SHIFT+T). Do note, however, that the selected text needs to be consistent. You cannot randomly select text that spans blocks of code and expect an adequate result.
The module editor now highlights all occurrences of the selected element when you click on it. For exemple if you place the cursor on the name of a template, all invocations of this template will be highlighted and markers will appear on the right ruler of the editor to indicate them.
Acceleo now provide quick fixes for some of the syntax errors detected in the editor, notably the possibility to create template or queries of a corresponding name.
It is recommended to use a bottom-up approach when developing generators ; Acceleo now eases this process by allowing you to initialize the content of a generation module with an example, and offering specific actions to transform these examples (static text) in dynamic OCL expressions. For example, changing all occurrences of MyClass to [c.name.toUpperFirst()/] in a single click.

Improvements and simplifications of the language

The MTL specification defines a standard library that offers a set of utility operations; in addition, Acceleo provides a non standard library to provide operations that greatly simplify the language and allow you to write more concise expressions, but are not part of the specification. This library has seen many additions since the 0.8 version, with things like Collections::sep(String) to insert a separator in-between every element contained by a collection, String::matches(String) to check whether a given String matches a regular expression, Collection::filter(Type) that can be used to filter out of a collection all elements that are not instances of a given type, Collection::reverse() to reverse the content of a given Collection... Take a look at the Acceleo documentation for a full reference of both standard and non standard library, along with the reference of the OCL standard library.
Acceleo allows you to alter the build mode, either Strict or Lax MTL compliance. Strict compliance meaning you'll get a warning for each use of a “non standard” operation.
Those of you that are familiar with the 2.x stream of Acceleo will be pleased to know that Acceleo 3 now provides the same post-processing facilities as its ancestor through the addition of a post directive on templates. Which allows for the modification of the text generated by a template “after generation”. For example, post(trim()) allows you to properly indent the content of the template while still leaving you the possibility to trim all unnecessary white spaces from the generated text.
The “+” operator can now be used whenever one of the operands is a String for concatenation, in order to avoid the verbose concat(String) OCL offers.
You can now use properties files to customize your generations through the addition of 4 variants of a getProperty operation in Acceleo 3. Once again, the operation reference can be looked at for the description of those services.
We made use of the facilities OCL provides in order to further simplify the navigation language : iterators of our [for] blocks are no longer mandatory (they'll be implicitly declared if needed and self can be used in their stead), you no longer need qualified names for your types when the metamodel is declared on the module header (or if it can be inferred from another of the declared metamodels), casting through oclAsType for all redundant expressions is no longer necessary...
For those expressions where OCL doesn't allow us to simplify the language, we added non standard operations. For example, sequence->select(oclIsKindOf(Type)).oclAsType(Type) is obviously redundant, but OCL doesn't allow for this expression not to define the explicit cast. In Acceleo, you can now write sequence->filter(Type) instead (see also my post on this specific issue).
Acceleo now allows for control characters (\n, \t, \'...) in OCL expressions.
Acceleo [for] blocks now declare an implicit “i” variable that can be used to retrieve the iteration count. For example, [for (Sequence{4, 5, 6})][i/], [/for] will generate 1, 2, 3.

Documentation

As advertised by Jonathan in one of his latest posts, the Acceleo documentation is complete and can be accessed from the integrated Eclipse Help through Help => Help Contents, in the Acceleo Model To Text category. We provide everything you need in order to get started with Acceleo; quick start, tutorial, user guide... and the full reference of OCL standard library and Acceleo standard and non standard libraries complete with explanations of the operations and examples.

Jonathan Musset: The Acceleo editor provides refactoring actions and quick fixes

jonathan.musset@obeo.fr (Jonathan Musset) — Mon, 31 May 2010 16:22:00 +0000

You can use the usual shortcut ALT+SHIFT+R to rename either modules, templates, queries, variables... in a coherent manner. This action can also be accessed from the menu Refactor > Rename. The interface will allow you to preview the changes before validating them.

Jonathan Musset: Code Generation Patterns

jonathan.musset@obeo.fr (Jonathan Musset) — Fri, 28 May 2010 08:29:00 +0000

The Acceleo IDE provides an extension point to help you to define your own code generation pattern proposals.

Here is an example available in Acceleo 3.0 (use the same way to define your own proposal) :

The extension point is org.eclipse.acceleo.ide.ui.proposal

The Java class implements "org.eclipse.acceleo.ide.ui.views.proposals.patterns.IAcceleoPatternProposal"

Generation patterns have been introduced in acceleo because we noticed that something that happens really often when developing code generators is the need to implement some behavior on an interface and all or part of its subtypes.

For example, let's imagine you are implementing a java generator from UML. What you want is to have a template called javaName which will generate the name of any classifier, with some default behavior and some specific behavior on classes and interfaces.

This is where the Generation Patterns view comes into play:

Locate the cursor in the template, at the position where you want to insert your javaName templates
In the Generation patterns view, select "[template] for all selected types" in the top part
Select the types for which you want to create javaName templates for

Note the bottom part of the Generation Patterns views presents a hierarchical view of the metamodel you are using. Each node represents a type of the metamodel and contains all of its subtypes. So, one type can appear several times in this view, one time for each of its super-classes or super-interfaces. When you select a node (by checking the combo-box before it), all its descendants are also selected by default, but you can uncheck those you don't need.

Once you have selected the types you need, go back to the editor and activate the completion by hitting Ctrl+Space. The first choice should be "[template] for all selected types", select it.

New templates are then inserted into you Acceleo module. They are called "name" by default but you can immediately rename them by just entering the name you want. All templates will be renamed simultaneously.

Here, Acceleo has done his job, now it's time for you to do yours: implement these newly created templates!

Laurent Goubet: Acceleo : OCL made simple

noreply@blogger.com (Laurent Goubet) — Thu, 27 May 2010 11:44:00 +0000

It was recently asked on a mailing list how one would order the elements they iterate over in an Acceleo for loop. The elements were UML ControlFlows as in :

- Package
|-- Activity
   |-- ControlFlow1
   |-- ControlFlow2
   |-- ControlFlow3

The first answer that came to mind, using standard OCL, was :

[for (cf:ControlFlow |c.ownedElement->select(a|a.oclIsKindOf(ControlFlow))->sortedBy(e: Element | e.oclAsType(ControlFlow).name))]
...
[/for]

Pretty verbose ... If we instead make use of the implicit iterators Acceleo offers, the expression can be simplified to

[for (c.ownedElement->select(oclIsKindOf(ControlFlow))->sortedBy(oclAsType(ControlFlow).name))]
...
[/for]

But this still sports the redundancy of filtering from a list only the elements of a given type (select) and then casting the elements to ... that very same type (oclAsType). This is due to OCL not allowing Acceleo to infer the return type of the select operation. Starting from Acceleo 3.0, this expression can also be written

[for (c.ownedElement->filter(ControlFlow)->sortedBy(name))]
...
[/for]

Now that's better!

Jonathan Musset: The Overrides View - Customize an existing code generator

jonathan.musset@obeo.fr (Jonathan Musset) — Thu, 27 May 2010 08:11:00 +0000

Thank you for following me on my "New Acceleo features" week ;-)

The Overrides view shows every Acceleo element that is accessible in your workbench (no matter your current project's dependencies). You can select one or several elements (use the checkboxes) and override them.

Note: If the meaning of "override" is not clear, you may want to refer to the official MTL Specification.

Templates displayed in this view can be anywhere in your workspace or in your plug-ins.

So, this view can be used for:

Selecting templates you want to override (which is its main purpose)
Navigating to templates in your plug-ins to see their implementation without having to explicitly import their plug-in(s) in your workspace.

To override one or several existing templates, just select them in this view by checking their checkboxes. Then, edit the module in which you will override the templates, place the cursor where you want to insert the overriding templates, and hit Ctrl + Space.

Select the first choice ("Selected Overrides") and hit Return. The overriding templates are then created. Note that by default, their implementation is initialized with their original implementation.

Note: A marker indicates whether a given project is accessible from yours. If this is the case, a green mark indicates everything is fine. Otherwise, a red marker indicates that you need to import the project in yours to be able to override a template it contains. For example, in the screenshot below, org.eclipse.acceleo.module.other.sample needs be imported in your current project before you can successfully override one of its templates.

Nevertheless, you can declare the overriding, it will just not compile while you have not imported the relevant project (which is done in the MANIFEST.MF file of your Acceleo project).

Jonathan Musset: Rapid Text Replacement in an M2T approach

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 26 May 2010 18:44:00 +0000

Here is a very useful trick in Acceleo. Rapid text replacement allows you to quickly replace all occurrence of a chosen piece of text by some template invocation. Case differences are inferred generating toUpper() or toUpperFirst() depending on what's needed.

Here is an example:

In a classical bottom-up approach, you have written your code first, and you now implement the Acceleo template from this code. What you want to do here is to replace all occurrences of "att1" by a dynamic behavior, i.e. by a template call.

The easiest way to do this is to select one of the "att1" in the editor, and invoke the content assistant by hitting Ctrl + Space.

The completion assistant proposes to replace all occurrences of the selected text by a template call. A preview of the result is displayed in a tooltip close to the completion window.

When you accept this option, all occurrences are replaced and you can immediately enter the template invocation needed, which is simultaneously replaced in all relevant locations.

All occurrences of att1 have been replaced by [javaName()/] (because javaName() is what was entered manually), but Att1 has been replaced by [javaName().toUpperFirst()/].

The next thing you'd want to do in the above example is to replace all occurrences of int by something like [javaType()/], and implement the javaType template to write the java type of the class attributes.

Just proceed the same way and you're done. No risk to forget any occurrence of your type anymore!

Jonathan Musset: Acceleo 3.0 Non-Code Aspects

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 26 May 2010 12:55:00 +0000

I was preparing the Eclipse Helios Release review material for Acceleo 3.0 and I had to compute the following information... I thought it could be interesting to share these Non-Code aspects with the Acceleo community...

JUnit Tests metrics :

706 unit tests are launched on every build
1219 unit tests are launched every day

JUnit Tests Code coverage :

71 % for the code generation engine
84 % for the MTL compiler
29 % for the Eclipse UI - We plan to reach 50% in the next few weeks

Code quality information :

Checkstyle is activated on each distinct plug-in
Eclemma is used on a regular basis to improve test coverage
Yourkit is used on a regular basis to improve performances
Javadoc represents more than 46% of the Java source code

A code analysis page is available on Ohloh.

Don't hesitate to become a friend ;-)

Jonathan Musset: Acceleo - Documentations are available

jonathan.musset@obeo.fr (Jonathan Musset) — Tue, 25 May 2010 14:02:00 +0000

The documentation that comes with Acceleo 3.0 is ready. Everything is available in the Help menu : Help > Help Contents > Acceleo Model To Text Transformation Language.

Each document of the documentation set deals with a different aspect of mastering Acceleo :

Plug-in Overview : This will give you at a glance a quick overview of what Acceleo offers.
Quick Start : This document is meant to help you get started with Acceleo as fast as possible. No details, no explanations, just the facts!
Android Tutorial : This is meant to give beginners a tutorial to get them started with defining their own code generators... and advanced users a way to discover some of Acceleo killer features.
User Guide : This document describes each and every feature of Acceleo. From the installation to the execution with a trip through the editing features, it will give you an in-depth description of everything there is to know about Acceleo.
New Acceleo Project : A short description of what a new Acceleo project has to offer (and how it should be laid out) in terms of files and features.
New Acceleo UI Project : Acceleo allows you to create "UI Projects" to ease the bundling and deployment of Acceleo generation modules. This short document will lead you through this process.
OCL operations reference : This is more of an OCL documentation, but this will give you an exhaustive list of the available OCL standard library operations, a short description and examples for each of them.
Acceleo operations reference : Same as the above, yet this time for the Acceleo standard (and non standard) libraries. Once again, a short description and examples for each of these operations will be listed.
Text Production Rules : This document is more of a normative document than it is an end-user documentation; it will help you understand the rules that Acceleo uses under the hood in order to determine when indentation should be swallowed, when lines should be indented, when lines should be trimmed...

Have fun and do not hesitate to give feedback through the mailling-lists, the bugzilla or the Eclipse M2T newsgroup! (you have to put the tag [Acceleo] in the message subject)

Jonathan Musset: Acceleo Pre-Conditions to improve adaptability

jonathan.musset@obeo.fr (Jonathan Musset) — Tue, 25 May 2010 12:59:00 +0000

Imagine you want to implement different behavior for a code generation template depending on certain conditions.

One way to do that would be to use if blocks to distinguish between those cases.
Another, more elegant, way is to use pre-conditions. Let's say that you want to generate different code for associations whether or not they are declared ordered.

The above example shows the ? (condition) syntax that tells Acceleo that the template must only be run if the pre-condition is satisfied.

Jonathan Musset: The Acceleo Result View

jonathan.musset@obeo.fr (Jonathan Musset) — Thu, 20 May 2010 17:56:00 +0000

In Acceleo 3.0, the Result View shows how the text, the templates, and the models are synchronized. After a code generation, select any element in the Result View and the associated generated code will be highlighted. Likewise, select any piece of code in a generated file, and you will see the associated element in the Result View.

You can also right-click on an element in the Result View and run: Open declaration. This will open the Acceleo expression associated with the element.

Yvan Lussaud: Agility 1.4 is out

noreply@blogger.com (yvan) — Thu, 20 May 2010 06:36:57 +0000

Agility is a product based on Eclipse that help migrating code. You can find more details here. This new release comes with several improvements :

- Custom link resolution
- OStore reflective editor
- Export to product parser

There are also bug fixes of course :)

Jonathan Musset: Dynamic Ecore with Acceleo - Editing and packaging

jonathan.musset@obeo.fr (Jonathan Musset) — Tue, 04 May 2010 08:39:00 +0000

In the Android example I presented at Eclipse Con 2010, we start by creating an ecore file with a set of domain model elements, including the "Activity" and the "Widget" concepts. When editing the code generation MTL module files, we need access to the Android ecore concepts. We need to improve both the ecore file and the code generator. It's easier to do if we are able to edit the code generator and the domain metamodel in the same eclipse instance.

We identify the domain ecore metamodel with its NsURI. In Acceleo 3.0, it is now possible to defined, in the MTL module file header, the NsURI of a dynamic Ecore/EPackage (even though it is defined in the same eclipse workspace). For instance, in the following picture, we are editing the "edit.mtl" file based on the "android.ecore" metamodel which is located in the same workspace.

The packaging of an Acceleo project is not more complicated than the packaging an Eclipse plug-in. In this case of a dynamic ecore file, you have to know that you need to export all the required plug-ins, including the project which includes the "android.ecore" file.

Jonathan Musset: Acceleo 3.0 : a pragmatic implementation of an OMG specification

jonathan.musset@obeo.fr (Jonathan Musset) — Fri, 30 Apr 2010 08:28:00 +0000

With Acceleo 3.0 included in Eclipse 3.6, our goal is to provide the de facto or reference implementation of the MTL code generation standard. Yet some parts of the specification are still quite vague and ambiguous and collaboration with OMG isn't smooth ... We follow as much as possible the standard but sometimes we need to introduce some deflections with the specification because we would like to keep the exemplary pragmatism of the Acceleo.org 2.x version.

For instance, we sometimes need to wrap Java services. It is useful to invoke some java code from inside an Acceleo template. The acceleo non-standard library provides a service "invoke" which allows just that. The invoked java service is wrapped in an Acceleo query. Such a service isn't defined in the specification but it is necessary in an Eclipse pragmatic implementation. For this reason, we decided to define 2 compilation modes in the Acceleo Compiler properties page. The default value is "false" for the "Strict MTL compliance" property. "unchecked" means that we allow to use the pragmatic non-standard library. When you check this value, some syntax errors could appear on your MTL files (each time you use the non-standard library) but the code generation execution still works...

Etienne Juliot will discuss about that (both the specification and the implementation) at the OMG Meeting Special Event on Tuesday 22nd June 2010 in Minneapolis...

Cédric Brun: Compare/Helios - Every Second Counts

noreply@blogger.com (Cédric Brun) — Wed, 28 Apr 2010 12:43:00 +0000

I tend to break a lot of keyboards. Not because I release all the aggression that I hold deep within me on them, but because I drool testing the product Obeo is going to launch really soon now.

During EclipseCon 2010 It struck me that some keyboards might have died because of EMF Compare. Ok, no more drooling here, the colors are nice, but when you are using compare with pretty decent models (like thousands of elements) you end up thinking it could be faster.

Hold your breath, order your very last keyboard which you'll use for a long time now, Compare's scalability has been improved a lot both in terms of performances and memory.

This work was pretty focused on the matching pipeline, there is room for improvements in the other parts of compare (especially the UI) but the matching was just so obviously slow and is even called 2 times for the 3 way match. That wa just making sense to fix things there.

The performance test case is using UML models containing 1,000 to 256,000 elements organized in a decent way and is matching them several times, here are the results before the scalability sprint:

Yes we have quite a strange value for the 1000 elements model, after investigation it looks like it's just some kind of corner case.

The last models have no time result for the simple reason they use all my memory and I end up with this dreaded OOM error.

Here are the figures after the sprint:

Now I can feel from here that you've been thrilled by all these figures and you only want one thing : to get your hands on this release. The Helios M7 release will be a good time to do so, wait for a few more days and go ahead: give us feedback !

Not only will the Helios release provide these major performances enhancements but the future looks even better: Stefan will work on a new match engine implementation focused on scalability for his google summer of code.

Waking up as every morning, getting up but being a bit happier than usual as I know I made progress on something important for adopters :)

Please, keep in mind that your feedback made me work on this, thanks again.

Laurent Goubet: Acceleo API and properties files

noreply@blogger.com (Laurent Goubet) — Wed, 28 Apr 2010 12:32:00 +0000

This post is aimed at anyone that depends on or make use of the Acceleo versions built and provided within the Helios release train, namely 0.9M1-0.9M5 and 3.0M6. If you are not concerned, feel free to ignore it altogether ^^.

We added support for ".properties" files in Acceleo in the latest development version (this support appeared for 3.0M1, at the time named 0.9M1). However we realized that this first version of the properties handling left no place for customization/overriding of properties ; no place for internationalization ; and deployment of generation modules as plugins would most likely cause issues with properties lookup. Bug 311045 and bug 311068 have been opened to track these issues.

If you are one of the early adopters that made use of the property support, you'll need to cope with a little change for the M7 build : in the generated class was an "addProperties" method which allowed you to registered the full path to the properties file that was to be loaded. For example if you had a file named "messages.properties" in package "sample" of plugin "org.eclipse.acceleo.sample", you had to register the path "platform://plugin/org.eclipse.acceleo.sample/sample/messages.properties".

You will now have to return a list through the method "getProperties" (well, "addProperties" is still there yet deprecated), and this list will have to contain "sample.messages" (that is, .) ; and properties file need to be located in source folders.

Likewise, if you had set anything as "generated NOT" in the generated launcher, you will have to manually go through some minor API changes as we ended up creating a common superclass for all launchers. Specifically, launchers now "extends AbstractAcceleoLauncher", and what was once private or protected is now mostly public. This means previously generated launchers that had set any method as "generated NOT" might have to enhance the visibility from private to public. Take note that previously generated launchers that have been built and deployed will not fail and can still be used as is, though enabling re-use of your generator can only be done by letting Acceleo regenerate it (or simply code yourself to take these changes into account).

Sorry about these changes (especially past M6), but we really thought best to remove the bug-prone behavior instead of trying to maintain it since it had never been released in a stable build. The new API should allow for a real use of property files and enhance the re-usability of any generation module.

If you wish to have a look at these changes and cope with them before M7 goes live, they are all accessible in the integration build I201004291415 that went live today (see the download page for the zip or all-in-one update site downloads).

If you have any doubt or questions about these issues, feel free to answer the m2t newsgroup thread I started with a copy of this post.

Laurent Goubet: OCL tips and tricks

noreply@blogger.com (Laurent Goubet) — Tue, 13 Apr 2010 13:45:00 +0000

Acceleo is entirely based on OCL (Object Constraint Language) for all of its model navigation syntax. Though we did simplify it as much as possible for Acceleo (getting rid of redundant casts, increasing the standard library, overriding operators, ...), there are still some things that might cause problems to any beginning user.

Here are a few of the most unsettling language particularities :

Operations or features conflicting with reserved OCL keywords (UML anyone?). For example, if your model has a class "Operation" with a feature named "body", then writing "myClass.body" in OCL will result in a somewhat cryptic error : "invalid token 'body'".
The trick to access such features in OCL is to prefix the feature name with an underscore. For this example, you should have written "myClass._body".
For the record, the full list of OCL reserved keywords as per the last available OCL version, 3.0, is as follows :
- and
- body
- context
- def
- derive
- else
- endif
- endpackage
- if
- implies
- in
- init
- inv
- let
- not
- or
- package
- post
- pre
- static
- then
- xor
Accessing enumeration values. This might sound obvious to OCL experts, but how would one compare feature values to set enumerated values? The trick here is to qualify the access. For example if you wish to check that an UML operation's visibility is "public", here is what you would do in Java : "if (operation.getVisibility() == VisibilityKind.PUBLIC".

The OCL equivalent is "if (operation.visibility = VisibilityKind::public)".

There is no "elseif" in OCL ; remember to close each individual if properly with endifs : "if (...) then ... else if (...) then ... else ... endif endif"

I believe these are the most annoying (as in "the most subject to cause weird compilation errors") OCL features ; don't hesitate to add yours :p.

Yvan Lussaud: Acceleo 2.7 is out

noreply@blogger.com (yvan) — Mon, 12 Apr 2010 02:17:35 +0000

There are several improvements and bug fix :

- Profiling now profile compilation of templates. EObjects profiling can
be also disabled. It's very useful when generating from big models.
- EA models import has been improved
- Some improvements have been done on resource caching
- A template extender have been added. It allows to explicitly extends
template from a module. It relay on extension point.
- It's now possible to add custom services as system services. For those
services the import statement is not required.
- The import order error has been changed into a warning.

For a more complete list you can visite the official Acceleo web site.
To download this new version you can use this update site http://www.acceleo.org/update.

Stéphane Bouchet: Acceleo Tip #3

noreply@blogger.com (Stéphane Bouchet) — Thu, 08 Apr 2010 16:31:03 +0000

Will the helios M6 release, each project have freezed their API. This was the last chance to implement or break API if needed !

I will just point something that changes with the last OCL 3.0.0M6 release.

This version introduced 'body' as reserved keyword for OCL so every metamodel that use 'body' as attribute name will have parsing errors from Acceleo !
see bug 305517.

But wait !

For EEF, we changed the metamodel to avoid collision, but for those who cannot change it, like UML ?

If you try the acceleo examples, there is the case with the UML2java example. for comments, there is the initial template used :
[for (cmt : Comment | o.ownedComment)] [cmt.body/][/for]

Acceleo will not be able to parse it, due to the 'body' keyword.

Here is the solution : prefix with the '_' character, aka '_body'. Acceleo will parse correctly and generates the correct code :

[for (cmt : Comment | o.ownedComment)] [cmt._body/][/for]

This may be disturbing the first time...

Freddy Allilaire: The new acceleo release before the 3.0 version

noreply@blogger.com (Freddy Allilaire) — Wed, 07 Apr 2010 18:59:21 +0000

Acceleo 2.7 has just been released. The Acceleo profiler has been improved in particular when generating from big models. A template extender was added; it allows to explicitly extend a template from an Acceleo module. Custom services can now be added as a system services. Several fixes were done on the models import from the Enterprise Architect modeler. Concerning the Acceleo modules, the C and Java modules have been improved. A new build is available on the update site.

Furthermore some bugs have been fixed; you may want to have a look on the new and noteworthy page for the 2.7.0 release: http://www.acceleo.org/pages/new-and-noteworthy-acceleo-2-7-0/

The "Acceleo modeling bundles" providing the Eclipse platform, Acceleo, its prerequisites have been updated. These bundles are the way to go if you want to test the power of modeling within Eclipse: http://www.acceleo.org/pages/download-bundle/ They provide as usual the ATL workbench for model to model transformations, EMF Compare for model comparison and others components composing the official Eclipse Modeling Package.

We planned several corrective versions for the 2.x branch: a 2.7.1 version will be released this year and a 2.8 version in 2011. But as you may know, the next major release of Acceleo is currently implemented and this new version is an official Eclipse foundation project (http://www.eclipse.org/acceleo). The most obvious change of this new version is the overhaul of the syntax as we now follow the OMG standard "MOF Model To Text Language" (MTL) based on OCL. In incubation since a little more than two years within Eclipse, Acceleo 3.0 is coming soon with the Eclipse Helios train (June 2010). Acceleo 3.0 already supports a level of functionality close to its 2.x stream. “Pre-release candidate” milestone could already be tested: http://www.eclipse.org/modeling/m2t/downloads/?project=acceleo

Do not hesitate to give feedback through the mailing-lists, the bug-tracker or the web forum, a Wiki is available to ease the collaboration and the gathering of tips and tricks. http://www.acceleo.org/pages/take-part-in-acceleo/

Thanks to all the developpers and contributors involved in this release!

Jonathan Musset: Acceleo 2.7 is released... Destination 3.0!

jonathan.musset@obeo.fr (Jonathan Musset) — Sat, 03 Apr 2010 14:32:00 +0000

Acceleo 3.0 is coming soon, with the Eclipse Helios train... Acceleo 3.0 already sports awesome stability and a level of functionality close to if not equal to its 2.x stream. We have planned several corrective versions in the next few years for the 2.x branch, the 2.7 version is out now! An official announcement will be done next week... Several improvements and bug fixes have been done for this release. You may want to have a look on the new and noteworthy page for the 2.7.0 release. We also plan to release a 2.7.1 version this year and a 2.8 version next year.

Do not hesitate to give feedback through the mailling-lists, the bug-tracker or the web forum... Note that Acceleo 3.0 users should use the Eclipse M2T newsgroup! (you have to put the tag [Acceleo] in the message subject)

Last news for Acceleo 3.0 users... We have just changed the MTL file editor icon because we would like to be as close as possible of the Eclipse user interface guidelines.

Here's an example of what we had before (the green icon) and what it looks like today...

Stéphane Bouchet: EEF M6 : ready to use for eclipseCon !

noreply@blogger.com (Stéphane Bouchet) — Tue, 30 Mar 2010 09:51:48 +0000

Just in time for EclipseCon, we are happy to announce the availability of EEF M6.

Some important news :
- EEF use the latest Acceleo 3.0.0M6 version. For those who wants to know why we are jumping from 0.9.0M5 to this version, read this
- EEF use also the latest OCL 3.0.0M6 version. Due to this bug , i urge you to validate your EEF models if you used filters.
- EEF is available in the helios update site.
- Goulwen will talk during eclipseCon, along with having free beer :)

Cédric Brun: I'm a poor, lonesome cowboy ..

noreply@blogger.com (Cédric Brun) — Fri, 26 Mar 2010 07:54:00 +0000

I'm a long long way from home.

And this poor lonesome cowboy.

Has got a long long way to roam ...

That's right, EclipseCon 2010 is over, each year it gets better and better and leaving it is always a bit sad.

I'll use this blog post as a memento of my feelings and the things I noticed during this week:

Many people are using EMF Compare. That should not be a surprise as it provides a key feature for anybody working with models, but still it gives me a warm feeling :) The ECon attendees provided me a lot of very relevant feedback, among others it looks like scability is not so nice when one is using a big model. Don't worry, I'll work on that (In fact I already started) and you can expect a performance boost, even for the generic engine. More of that in a future blog post with figures.

People are now used to the idea of e4 is going to exist, it will provide new means for writting application, I also have the feeling that people understood that e4 is going to be what WE as a community, wants it to be.

Chocolate fountains are not mandatory, but some bugs will always arise.

ATL is definitely THE model to model transformation language, it's mature, and now thanks to William's work the tooling is a bit closer to the perfection.

CDO is one of the most amazing framework I had the change to use, it's quite unbelivable that such a small and slim framework can provides you such a power. You need years of engineering and professionalism to achieve this. congrats to the whole CDO Team !

I have a lot of hope for the Mylyn Review project, the approach is simple but perfect for people like me, it will just be "yet another key feature" of the IDE. In fact the whole Mylyn project is providing, as usual, innovations.

The Sharks Rocks ! They blasted the Dallas Stars ! And I guess I'll be more interested about hockey now :)

Pascal has not been abducted by aliens, he is still the same although being transformed in a Maven guy now.

Modeling is everywhere. It's just pervading on everything : from your IP Log to the next generation platform you'll rely on.

End users really appreciated the work I did on the modeling package, Here again, thanks for your feedback.

Xtext was everywhere, and will be a key asset for the upcoming IDE generation.

The Eclipse Foundation did a tremendous work for this event, and it' s been perfect ! Thanks again !

Acceleo is so powerful that many people expressed their wish to use it for their code generation needs : step one on the "taking over the world" plan is validated.

Nasa, Rockets and Robots are cool.

The Architecture Council is taking more and more initiative and Martin is doing a great job driving it.

Now that EMF is everywhere everybody wants to use EEF

Huge companies like SAP or Thales are building their tooling strategy around Eclipse - not only as a platform but also as a community.

I already said "No" to my manager at least two times !

Such a conference in an hotel can work, and it's actually even better than in a Convention Center, we have nice couch, a bar, it makes discussion way easier.

Having tutorials in the morning during the whole week is great, then you start smoothly, learn things and code : I can fill my addiction.

It's possible to create a conference program of high quality (the best I had in the previous four years to my opinion), with such a diverse community. Kuddos to Oisin !

I'm pretty sure I'm forgotting things, but anyway, I really need to sleep now...

In a nutshell : the best conference ever :)

Jonathan Musset: Eclipse Con 2010 and Acceleo community feedbacks

jonathan.musset@obeo.fr (Jonathan Musset) — Wed, 24 Mar 2010 22:12:00 +0000

Eclipse Con seems to be a great success this year, like every year ;-)

I have particularly liked the Jeff Norris keynote this morning. What a standing ovation! Thank you Jeff for the road trip on mars...

Thanks also to you Kenn for the nice Eclipse Modeling Runaway 2010. It was a pleasure to talk a little bit about Acceleo. For those of you who are interested, here is the fash demo I have shown during this session : Acceleo at Eclipse Modeling Runaway 2010.

Here are the slides of my 25 minutes session Acceleo Code Generation - Let's start with an Android example. I hope that you liked it... Let's me know if you have learned something. I had 3 goals when I made this quick tutorial :

Acceleo beginners could see a simple but concrete case-study

Acceleo addicts could discover some new "killing" features, for the Obeo guys also ;-)

Android experts could learn enough of the basics to be able to create advanced code generator in a few days

I'm not an Android expert but I like this technology and I have liked to make a quick example on how to use Android and Acceleo together. To be continued...

Cédric Brun: Diff, Merge and Patch your Models with Helios

noreply@blogger.com (Cédric Brun) — Wed, 24 Mar 2010 06:12:00 +0000

Ok, you're stuck at home, you are one of the numerous budget shortcuts victims ? You did not had the chance to come at EclipseCon ? Here is some kind of transcript of the talk I just gave:

This talk will tackle team-working with models. Once you use models in your development proces, they matters as much as the source code. Don't you want to be able to diff, merge or even patch your models just like with text files ?

The good news is that unlike text files models have a semantic structure defined thanks to their ecore model, as such we're able to semantically compare the models, comparing the serialization (XMI or other..) is often meaningless.

By the way I'm the project lead of EMF compare, the project has been contributed in Eclipse in early 2007, at that time many EMF adopters realized that this piece was missing in the Modeling ecosystem and this lack was often a blocker !

So here we are, three years later. EMF Compare - in the EMF Technology project at first- graduated and is now part of the EMF project itself !

Just like Transaction, Validation or CDO, Compare is one of the many pieces you can reuse as a framework, or just as a tool. Its focus is quite narrow : comparing, merging and patching any kind of EMF model, the later being an UML model or a domain specific one.

As we graduated we've been focusing on keeping stable API you can rely on. We really think that EMF popularity is highly due to the fact that depending on it is easy as it is completely forward compatible. Working nicely as a pure Java jar library is another key asset of EMF, we tried to stick to that for the Compare project: our framework can be used as a Java jar, not depending on Equinox or any extension point.

We could phrase the Eclipse IDE spirit in : be extensible, be customizable, be integrated. We are sticking to this motto too, you can extend or customize any part of the comparison process.

The compare and merge features are completely integrated with the Eclipse Team API. When you launch a comparison from the workspace or from an history, if the file is in fact a model, EMF Compare will be opened and will show you the differences, allowing you to merge, or switch back to the serialization diff.

Let's have a look on the tool through a demo. This demo goes higher and higher in coolness, as such it's starting by comparing an old fashioned UML model on a dying CVS Repository.

A bit more cool : comparing a domain specific model on a SVN repository.

Total coolness : comparing an XText DSLsemantically, merging it, on top of a GIT repository !

That's just the tip of the iceberg, EMF Compare has a few more features and is especially useful in a lot of contexts, rather than listing all these details I'll focus now on the inside, revealing you which kind of magic make this clock ticking.

As I said at the beginning, the good news comparing models is that we've got semantic information we're not comparing plain text. There is a drawback though: models are graph and as such being able to match similar graphs is a complex and tricky problem.

The first thing we have to do for a comparison is to match the elements from both versions of the model.

If you've got ID's that part is trivial, EMF Compare will use your ID's (either business one or technical ones). On the other hand if you don't, we are providing what we call the "generic match engine", this engine uses a few statistical metrics to match the elements.

For a given element this engine will extract it's type information, the content values, its relations with other elements and its name if we can detect one. Each piece of this extraction will be compared with other elements to compute a similarity coefficient, from this one we can try to get closer and closer to the perfect match.

Once this engine has done it's job, it provides a Match Model grouping all this information and weaving the other models.

It gets more complicated, (and then more interesting) when using source control management systems. Then you have to match three versions of a model: yours, the remote one, and the common ancestor between those versions.

To do so we builds two match models, between your local version and the common ancestor, then between the remote version and the common ancestor, and we combine those two match models into one, weaving the three models altogether.

At this stage it should be obvious that the faster the match engine is, the faster you'll get a result.

To be honest the generic match engine is not so fast, having little clue about the models it's matching it spends a lot of time browsing the structure, trying to match things which probably have no possibilities of being the same..

Being aware of that we eased the definition of your own match engine specific to your Ecore model. In doing so no doubt you'll get better results and way faster.

Let's take a step back. What are we trying to do ?

We are trying to change two versions of a graph into a set of events, in reality we are trying to re-construct "a posteriori" the history of the graph: what changes have been made to transform the original one to the new one.

Match computation is done by the Match Engine, the Diff one by the Diff Engine. This processor has to provide a Diff Model from a Match Model.

In fact, when you have the MatchModel, deducing the DiffModel is not a huge task, you basically have to browse the matched elements, checking for changed attributes and reference, and then create for each "unmatched element" the corresponding deletion or addition event.

Here again, you can plug in your own diff engine, and you can even define your own diffs specific to your formalism. Instead of having a "stock value changed from 12 to 34" event you can define yours as being "stock value has been increased from 12 to 34" and even aggregate several atomic diffs in a single top-level one.

Being a first class model itself, the diff model can be leveraged through model to model or model to text transformation to publish the changes to another format.

Now you should have a basic understanding of what EMF compare is trying to solve and in which way. We've seen that stability both in term of API and code was our primary goal right now but does that means nothing new is being done in Compare ?

For Helios we fixed many issues thanks to the community feedback, support for fragmented models and matching of referenced resources has been greatly improved.

The primary feedback is bug reports, but we also had quite a few contributions among those a new API to scope the matching process and a whole new set of plugins to create model independent diffs resilent to transformations in the model you want to apply the diff on.

So many things to discuss in such a short time frame.

Give it a try, EMF Compare is part of the Eclipse Modeling Platform SDK, download the package and you're done.

I would be happy to discuss with you, either IRL or through electronic means. Please uses the EMF newsgroup, the bugzilla or the #eclipse-modeling IRC channel on freenode. We're also available and new trendy channels like Twitter : @bruncedric.

Want's more ? Have a try downloading the Eclipse Modeling Package !