Friday, December 12, 2008

Equinox Aspects 1.0 M4 available for download

The forth milestone build of Equinox Aspects is available for download. This build focuses on improving stability and reliability. Take a look at the 1.0 M4 New & Noteworthy page for more details and a list of fixed bugs.

Wednesday, December 03, 2008

Next version of AJDT uses Equinox Aspects

This morning I read this mailing list posting about using Equinox Aspects on the AJDT and AspectJ lists. Great to see that the AJDT team is going to use Equinox Aspects as supporting technology for the 1.6.2 release coming up at the end of this month. If you are interested you can find more details on this wiki page: JDT weaving features.

Friday, November 21, 2008

Slides and more from Eclipse Summit Europe 2008

I am back from the Eclipse Summit Europe 2008 in Ludwigsburg and found the time to put the slides from the talk on Equinox Aspects online (pdf). The slides are pretty much the same as from the previous talks I gave on aspect weaving for OSGi during the past weeks, so you won't find real new stuff in it. Nevertheless, giving this talk is just plain fun.

The RT symposium (I helped Heiko and Jeff a bit to organize it) on Tuesday morning was more or less an open discussion about topics around the RT project. We asked for answers to some questions upfront to the meeting and discussed those during the first part of the symposium. For sure some nice and interesting discussions came up during this. Nevertheless the second part of the symposium was a lot more lively and interesting from my point of view. We collected some topics, prioritized them and discussed them in the prioritized order (maybe something like "Open-Space Light"). There was a lot more discussion going on, more participation, sometimes even a bit controversal. Great. If I will participate in organizing such a symposium again sometime in the future, I will definitely vote for doing more (if not all) of the symposium that way.
A rough outline of the symposium can be found at the RT-Symposium-at-ESE-2008 wiki page. And I can recommand watching the video podcast that Ian Skerrett recorded together with Jeff about the RT symposium. Its fun watching... :-)

This was not the only video that Ian recorded at the event. He interviewed all the symposium organizers and published these great video podcast episodes (series 1, series 2). Thanks a lot, Ian, for these video podcasts. Absolutely great!!!

Wednesday, November 05, 2008

Slides from WJAX 2008 online

Still being at the WJAX conference in Munich I took the time to put the slides online from all the talks I am involved in: Enjoy!

Sunday, November 02, 2008

Equinox Aspects 1.0 M3 available for download

The third milestone build of Equinox Aspects is available for download. This build focuses on improving stability and reliability and implicates major enhancements to some internal implementation details of Equinox Aspects. Take a look at the 1.0 M3 New & Noteworthy page for more details and a list of fixed bugs.

Saturday, October 25, 2008

Looking forward to WJAX and Eclipse Summit Europe

Saying goodbye to OOPSLA I am already thinking about the next two conferences coming up on my schedule and which are highly promising to be very very interesting. In a bit more than one week there is the WJAX conference in Munich, Germany. The program is fully packed with interesting stuff and I am quite happy to talk about some cool stuff as well.

Starting on Monday I will participate in the Agile Day at WJAX where I will talk together with Norbert Grosz about experiences from introducing agile development to an insurance company.
Next is the OSGi Special Day on Tuesday. Together with my colleaque Matthias Lübken we will talk about moving existing applications towards using OSGi. Later that day I will give my fun talk about classloading and type visibility in OSGi - I still love classloading stuff. :-) Wednesday I have the pleasure to share my experiences from using and adapting "The Eclipse Way" (the famous development process of the Eclipse team) for general in-house projects. And finally on Friday, at the OSGi Experts Day, Heiko Seeberger and I are going to showcase Equinox Aspects to the attendees. This will be a real fun week in Munich!

Not far away from WJAX is the Eclipse Summit Europe, starting at Tuesday, November 18th, in Ludiwgsburg, Germany. Together with Jeff McAffer and Heiko Seeberger I am organizing the Runtime Symposium on Tuesday morning. Take care you don't miss this symposium to meet people who are also interested or involved in the runtime projects at Eclipse. In addition to that I will give (together with Heiko) a short talk on Equinox Aspects on Wednesday.

And last but not least I would be really happy to hear from you what you would like to know from the talk on classloading and type visibility in OSGi. If you have any questions you would like to get answered within that talk, please comment on this blog entry. I will try to incorporate them into the talk.

See you there!

Thursday, October 23, 2008

Slides from OOPSLA 2008

The slides of my OOPSLA demo on Equinox Aspects are now online - together with those of my tutorial about Spring Dynamic Modules:
Enjoy!

Thursday, October 09, 2008

Building Platforms with Jeff McAffer on SE-Radio

Two days ago the episode that I recorded together with Jeff McAffer about building platforms was published at SE-Radio. I enjoyed a lot asking Jeff so many questions about how to build successful platforms, good APIs and those things and got many very valueable insights. Don't miss it!!!

Saturday, October 04, 2008

New version of Spring Extension Factory available

When retrieving an OSGi service its good practice to use a timeout. Otherwise the operation could be blocked forever (in the case the service never appears). In past versions the Spring Extension Factory used a hard-coded timeout of 5 seconds. I chose this value more or less randomly, guessing that no bundle would hopefully need for than 5 seconds to create its application context. But I was proven wrong... :-)

Therefore I made the timeout setting configurable. Now you can define the timeout value (in milliseconds) via a system property called "org.eclipse.springextensionfactory.timeout". To set the timeout to 20sec, for example, start the JVM with this option:

-Dorg.eclipse.springextensionfactory.timeout=20000

I also added some more readable exceptions if no application context can be found or if the name of the bean to be used cannot be determined.

The new version can be downloaded from here:
Thanks for reporting the problem, Matthias!

Thursday, October 02, 2008

Eclipse Demo Camp in Hamburg - November 2008

After the great success of the Eclipse Ganymede Demo Camp 2008 in Hamburg in June this year Peter Friese and I are organizing another Demo Camp in Hamburg at the 10th of November. It will take place at the East Hotel, a very fancy design hotel in Hamburg.

The schedule for the demo camp is not finished yet. What we already know is that Harald Wellmann will talk about "Geodata Processing for Car Navigation Systems" on top of OSGi and Gerd Wütherich will give a quick demo on Spring Dynamic Modules. And there will be some more, I am sure.

Don't miss it! You just need to register at the wiki page, come by at the 10th of November and enjoy the demos, food, drinks and other Eclipse enthusiasts. I am looking forward to seeing you all there!

Tuesday, September 30, 2008

Dynamic OSGi Applications (at WJAX 2008 and OOP 2009)

In the past years I have used OSGi mostly because of the modularity features. I loved to create small bundles with clear dependencies and visibilities between them - and I still do. I missed this kind of modularity in Java for so many years and I think that many teams still disregard this important modularity for their systems.

But I always knew that the module layer (the one I love so much) is only a small part of the OSGi world. The real coolness of OSGi comes with its dynamics. Using OSGi you can install, update and uninstall bundles at runtime without restarting the JVM. Wow! Doesn't this sound cool?

But wait. What the hack does OSGi do in those situations? If I start my applications, maybe thousands or millions of objects are created, relaxing in memory, referring to each other, talking to each other. Now this thing called OSGi updates a bundle at runtime. And my lovely objects? Are they updated magically under the hood and I don't need to take care of anything? Unfortunately (or I would say fortunately) not!!!

Nothing is done to my objects automatically. Instead I need to take care of those situations myself (which is good news in some way). I need to understand what it means having bundles that can come and go while my system is running (maybe under high traffic). And I need to carefully design my bundles to behave nicely within those situations.

Although its mentioned in every presentation on OSGi I assume that many people still don't know what this really means for building typical business applications. So many (and this includes myself) are used to build systems that are more or less a static set of deployed classes - once a release is deployed and used. Developers typically don't think about parts of the system being installed, updated or uninstalled at runtime without shutting down the application itself. And I think the structure of those systems reflects this. Even if the application is built out of a set of small bundles with clearly defined dependencies - in the end the transitive closure of the main application bundle contains everything. And the app assumes that once I have a reference to an object, this object will stay with me (and be fine) forever.

I observed this situation in some projects and it made me think about it from time to time. I talked to colleagues (namely Gerd Wütherich and Kai Tödter) about this and we discussed our experiences. The result is that we currently try to find some common best practices and patterns to write more dynamic systems than we did in the past for an upcoming talk at WJAX 2008 and OOP 2009.

I am pretty excited that there is so much more to learn how to build really dynamic systems with OSGi and I am sure that this will change the way I write and structure OSGi bundles in the future. Yours, too?

Monday, September 22, 2008

"About-us" episode at SE-Radio

In between the general 10-days-schedule the SE-Radio team has published a short episode about SE-Radio itself. So if you want to know more about our download statistics, the team members, sound quality and more go to: SE-Radio Episode 111: About Us 2008 and enjoy!

Saturday, September 06, 2008

OOPSLA 2008 Podcast is Online

The first episodes of this years OOPSLA podcast are now online and it should be fun to hear what is coming up at the conference. The list of interviewees sounds very promising. :-)

It's again produced by DimSumThinking and SE-Radio. I am pretty excited and feel honored to be the one at SE-Radio who coordinates the episodes and records some of them. But again, without the enormous help of Markus (who records the other half of the SE-Radio-produced episodes) this won't be possible at all. So thanks again for all your help with this, Markus!

Wednesday, August 13, 2008

Bugfix for Spring Extension Factory available

I fixed a problem that prevents the Spring Extension Factory (which I originally described in this post) to work for bundles with Eclipse-LazyStart set to true. The new version works for bundles with or without the layz start setting:
Thanks for reporting the problem as well as a solution, Jimmy!

Friday, August 08, 2008

Equinox Aspects 1.0 M1 is out

The first milestone build of Equinox Aspects 1.0 is available for download from the Equinox Aspects download page. Take a look at the M1 New & Noteworthy page for details.

I am especially happy that this milestone brings OSGi dynamics to aspect bundles. This makes AOP a much better citizen of the OSGi world and gives you a feeling of dynamic AOP, which is really cool... :-)

And I need to mention that the performance of the standard caching has improved a lot. We are now very very close to our goal of running a woven system from cache at the same speed as without aspects.

Monday, August 04, 2008

Demo on Equinox Aspects at OOPSLA 2008

I am happy to announce that a demo on Equinox Aspects is accepted for presentation at the upcoming OOPSLA 2008 conference in Nashville, Tennessee (Oct 19th-23rd). So I would be very very happy to see you all there!!!

Monday, July 28, 2008

ObjektForumNord about OSGi with Peter Kriens

I am pretty exited that Peter Kriens will join us for the ObjektForumNord (website in German, sorry), a series of talks in Germany. This time the session is in Hamburg (my hometown) and Peter is going to give a tutorial and a talk about OSGi. During the afternoon of September 9th, he will give an introductory tutorial about OSGi together with my colleague Matthias Lübken. The evening is filled with Peters talk on "Why Modularity is Important". I am really looking forward to it. Don't miss it.

Sunday, July 27, 2008

News from Equinox Aspects

Some people might have noticed already that some changes are going on inside the Equinox Aspects incubator. Heiko posted the details to the mailing list: http://dev.eclipse.org/mhonarc/lists/equinox-dev/msg04653.html.

I am pretty exited that we are moving towards being a better citizen of the Eclipse world. We have re-arranged our development process and aligned it with the process of the other projects at Eclipse. Take a look at our milestone planning and details on what keeps us busy at the Equinox Aspects Plan wiki page.

The first milestone is targeted at the 8th of August, less than two weeks from now. And on the way from milestone to milestone you can watch and test the progress by using the development builds from our download page.

Friday, July 25, 2008

Episode on Plugin Architectures at SE-Radio

Last weekend SE-Radio published an episode about plugin-based architectures. Within this episode I talk with Klaus Marquardt about different kinds of plugins and different kinds of systems build with or out of plugins.

This episode was actually my first episode as host and we recorded it a long long time ago. But listening to it today disappoints me somehow. The episode contains a larger number of repetitions from my side and I didn't achieve to make it a condensed episode. Just to be clear: This was not the fault of Klaus, whom I interviewed in this episode - not at all. Again it reveals that recording podcast episodes is a learning process - just like software engineering is.

"Silver Medal" for Equinox Aspects Talk

The attendees session ranking from Java-Forum-Stuttgart 2008 is now online and I am more than happy to see that my talk about Equinox Aspects (slides, code examples) won the silver medal. How cool is that? And its great to see that more and more people are interested in Equinox Aspects. Wonderful...

Saturday, July 12, 2008

Dependency Injection for Extensions, Third Edition

As you might have read from my previous posting I created an example that demonstrates the usage of Equinox Aspects as the load-time weaving engine for Spring Dynamic Modules. Now its time to describe this in more detail. :-)

My first idea behind this combination was to use the @Configurable annotation to use Spring's dependency injection mechanism for arbitrary objects which you typically don't create via the application context of spring. The default examples for this are plain domain objects, extensions are another example (they are typically created by the extension registry of Eclipse). Spring realizes the dependency injection for those objects by weaving an aspect into their classes. This aspect takes care of injecting the dependencies after each object creation. And this is the point where Equinox Aspects comes into play.

Fortunately Spring ships as a set of OSGi bundles. This is also true for "spring-aspects.jar", the JAR archive that contains the aspect that is responsible for making the @Configurable annotation work. And you can use Equinox Aspects to weave this aspect into your bundles wherever you would like to use the @Configurable extension. Sounds good, eh?

Ok, what do you need to do? Let’s go through the example step by step. First you need a target platform that contains the following:
Now you have a class that would like to use @Configurable. In my example it is a view for an RCP application that looks somewhat like this:

@Configurable
public class View extends ViewPart {

private Service service;

public void setService(Service service) {
this.service = service;
}

public void createPartControl(Composite parent) {
...


Then you define in the spring context of the same bundle the view as a spring bean, including the "service" property (the dependency that should be injected):

<bean class="org.eclipse.example.springdm.rcpview.View" scope="prototype">
<property name="service" ref="myservice"/>
</bean>

<bean id="myservice" class="org.eclipse.example.springdm.rcpview.Service"/>


Take care to define the bean for the view as of scope "prototype". This is necessary to tell spring that this bean definition should be used as prototype for various instances.
Now we need to tell your bundle to be woven with the spring aspect. Therefore you just define the aspect bundle as required bundle:

Require-Bundle: org.eclipse.ui,
org.eclipse.core.runtime,
org.springframework.bundle.spring.aspects


Now Equinox Aspects (if started correctly) weaves the aspect into your bundle wherever the @Configurable annotation is used. The next step is to tell the spring context that it should use load-time weaving and annotation configuration (plain old spring configuration for load-time weaving, nothing special here):

<context:spring-configured>
<context:annotation-config>
<context:load-time-weaver class="org.springframework.instrument.classloading.InstrumentationLoadTimeWeaver">


This also requires some more import package statements within your manifest:

Import-Package: org.aspectj.lang,
org.aspectj.runtime.reflect,
org.springframework.instrument.classloading,
org.springframework.beans.factory.annotation


The first two import statements are necessary because they are needed if an aspect gets woven into one of your classes. A more elegant solution for this would be to reexport those packages from the spring-aspects bundle, but they didn’t define the reexport in their manifest. Therefore you need to import them manually.
The last step is to take care of the startup sequence of your bundle. If the extension is created, your bundle should be activated to get the spring context created. This creation of the spring context should happen synchronously to ensure that the context is created when your extension object is created – otherwise the dependency injection would not work. Therefore I declare in the manifest:

Eclipse-LazyStart: true
Spring-Context: *;create-asynchronously:=false


If you would like to take a look at the complete example that I used, you can download it here:



Feedback and questions are always welcome!

Code Examples from "Aspect Weaving for OSGi" Talk

As promised, here are the projects of my live demos from "Aspect Weaving for OSGi" at last weeks Java-Forum-Stuttgart 2008.

Eclipse Monitor Demo

This demo features the relatively old Eclipse Monitor application that Chris Laffra wrote a while ago. It visualizes plugin activities within your Eclipse application and you can analyze what is going on. This monitor uses Equinox Aspects to weave an aspect into all your bundles at load-time to gather the information of what is going on at runtime. It uses AspectJ advises for all methods and object creations. While this is a pretty heavy use of load-time weaving (you will notice a huge performance impact at first startup) it demos nicely the caching feature of Equinox Aspects. The second startup of your monitored app will perform very similar to a startup without any aspect weaving.

To run the example: Within your development environment you should have AJDT installed to work with AspectJ. In your target environment you should have included your favorite IDE (as example RCP app to monitor), the matching AJDT version, and the latest Equinox Aspects development build from here: http://www.eclipse.org/equinox/incubator/aspects/equinox-aspects-downloads.php. Notive: You need to install the latest dev build, not one of the archived builds. Once you have this you should be ready to run the example. Just import the projects in your workspace and use the included launch configuration.

Dependency Injection with Spring Dynamic Modules and Equinox Aspects

Spring provides this nice mechanism to inject dependencies in domain objects via the @Configurable annotation (see more here: http://static.springframework.org/spring/docs/2.5.x/reference/aop.html#aop-atconfigurable).
The main difference to general spring beans is that the creation of those domain objects is not done by the application context of Spring. Therefore Spring uses an aspect to call the application context after object creation to inject all necessary dependencies. In plain old Spring applications this aspect is woven into the system using load-time weaving.
Wouldn't that be a nice mechanism to inject dependencies into Eclipse extensions (like views or editors)? Just annotate your extension with @Configurable and define the dependencies to be injected inside the application context of your bundle (using the Spring Dynamic Modules stuff)?

One way of doing this is to use Equinox Aspects together with Spring Dynamic Modules. Just use the spring-aspects.jar from your spring distro (its already an OSGi bundle) and enable Equinox Aspects weaving - and you are done. It just works! :-)

To run the example: You don't need any special support within your development environment. Instead your target platform should be configured carefully. For the example projects I used Eclipse 3.3.2 as target platform, added AJDT, added the latest dev build of Equinox Aspects, Spring 2.5.4 bundles and Spring Dynamic Modules 1.1.0 bundles. Import the example projects from the zip file into your workspace and use the included launch config to run the demo. The example injects a spring bean into the view extension.

I will give more detailed information on how this Equinox Aspects weaving can be used together with Spring Dynamic Modules in an upcoming post.

If you observe any problems or if I forgot something in this description, please let me know.

Have fun with the examples!

Thursday, July 03, 2008

Slides from "Aspect Weaving for OSGi" Talk

This morning I gave a presentation at the Java-Forum-Stuttgart conference on Aspect Weaving for OSGi. The slides of this talk are now available for download:
The code for all live demos from the presentation will follow shortly.

Tuesday, June 24, 2008

Reminder: Equinox Aspects at Java-Forum-Stuttgart 2008

This is just a friendly reminder that you have the chance to see Equinox Aspects live and in action at the upcoming Java-Forum-Stuttgart 2008 next week at the 3rd of July. I will give a talk at this nice conference in Stuttgart, Germany, about Aspect Weaving for OSGi. And the talk will be fully packed with a number of live demos including:
  • Monitoring Eclipse with aspects
  • Installing, updating and uninstalling aspects at runtime (dynamics for aspects)
  • Using Equinox Aspects together with Spring Dynamic Modules
It will be really really cool, don't miss it! :-)

Sunday, June 22, 2008

Slides and Examples from Spring-Dynamic-Modules-Talk at the OSGi Community Event 2008

Already more than a week ago I gave a talk at the OSGi Community Event 2008 in Berlin about the Spring Dynamic Modules project. Giving the talk was fun, I used a number of live demos to showcase Spring DM in action. The slides are now online:
The code for all the demos can be found at the JAX blog entry of my colleque Gerd Wütherich, who prepared most of this talk. Thanks again for the great work, Gerd!

For those who are new to Spring Dynamic Modules: This project of the Spring portfolio basically allows you to use the Spring framework within an OSGi environment in a very nice and easy way. You can find more information on the Spring Dynamic Modules homepage.

Thursday, June 19, 2008

Report from Eclipse Demo Camp in Hamburg

Last Monday the Ganymede Eclipse Demo Camp took place in Hamburg. More than 40 attendees showed up and enjoyed a number of great presentations. Peter Friese wrote up a nice summary of the demo camp. I enjoyed the event a lot and I am looking forward to organizing the next Eclipse Demo Camp again together with Peter. Was a lot of fun! Thanks Peter!

Also many many thanks to Arne Roock for his great support in organizing the event and finding this cool location! His support is absolutely priceless!!!

Tuesday, June 10, 2008

Eclipse Demo Camp in Hamburg is Approaching Fast

Don't forget to register for the Eclipse Demo Camp in Hamburg - it is approaching fast. Starting next Monday at the EM-2008-friendly time of 6pm we will see some interesting demos, have free drinks and food (thanks to our sponsors: Eclipse Foundation, itemis and it-agile) and a lot of fun, I assume... :-) The demo camp takes place at the former coffee exchange - a really cool location:


So, have fun at the demo camp and many thanks to my colleague Arne Roock for his organizational support. Absolutely priceless.

Sunday, June 08, 2008

Equinox Aspects at Allianz

Some days ago I got a copy of the latest German Eclipse-Magazine (Vol. 15, 3/2008) and I found an experience report article about using Equinox Aspects. Cool! Great to read that people are using Equinox Aspects in large strategic projects. This report is about using Equinox Aspects for advanced performance tracing in a large production system at Allianz, a major insurance company in Germany. So if you are happy reading articles in German, take a look at it!

Thursday, June 05, 2008

SE-Radio Live at the OSGi Community Event 2008

The OSGi Community Event 2008 starts next week in Berlin, Germany. And there will be a special event taking place after the reception on Tuesday evening: We will host a live SE-Radio recording session. Isn't this cool? We are going to have a panel like discussion session with some interesting people and hopefully questions from the audience - all going into the se-radio recording and becoming part of that episode. So if you are going to the OSGi Community Event make sure you don't miss the SE-Radio live session - from 8pm to 9pm in the main room.
And many many thanks to Peter Kriens for making this possible and helping so much in organizing this!!!

Wednesday, June 04, 2008

Open XP-Days Germany 2008

The XP-Days conference series is a nice event series throughout Europe for people interested in agile software development (not reduced to Extreme Programming) and related topics. This years XP-Days Germany will take place in Hamburg from November 27th to 29th.
In opposite to the past XP-Days this years conference has an open review process in parallel to the submission process. This idea has two great advantages: everybody can review and comment on submissions via the submission system and people who submit sessions can benefit from those reviews and feedbacks by improving their submissions before the program committee decide. Sounds good, eh? I am used to this kind of open submissions from the EclipseCon conference and I must say: I like it a lot.
So don't forget to submit a proposal or give feedback on existing proposals - or simply join the conference this November!!!

Wednesday, May 28, 2008

Dependency Injection for Extensions, Second Edition

At this years EclipseCon I implemented an extension factory utility that could be used to delegate the creation of an extension object to a spring context (if you are using Spring Dynamic Modules). The result was that you were able to define your extensions as spring beans including all the nice spring features (dependency injection, aop, dessert topping, whatever...). That first implementation was nice, but had a number of stupid limitations (worked only for active bundles, for example). The good news is: A new version is available that includes some nice improvements... :-)

Firstofall, here is the new version of the Spring-Extension-Factory:

The new features are:
  • Ability to declare the bean-id explicitly within the extension definition

  • Automatic start of non-active bundles (and application context creation via Spring Dynamic Modules) when an extension is being created

How can I use this extension factory? Lets look at some examples. Lets assume you implement an RCP application and you would like to define a view as spring bean to inject some dependencies. First, you declare your spring bean inside the spring context:
<bean id="myview"
class="org.eclipse.example.springdm.rcpview.View"
scope="prototype">
<property name="myService" ref="serviceBean"/>
</bean>


Okay, this defines the spring bean called "myview" and injects a bean with the id "serviceBean" as a dependency into my view. The class of the view is the normal view implementation that you are familiar with. Don't forget to declare the bean as of scope "prototype". Otherwise spring would return always the same object every time an extension should be created (which is not the contract of the extension mechansim).

Now we define the extension in the plugin.xml file:
<extension point="org.eclipse.ui.views">
<view name="Message"
allowmultiple="true"
icon="icons/sample2.gif"
class="org.eclipse.springframework.
util.SpringExtensionFactory:myview
"
id="org.eclipse.example.springdm.rcpview.view">
</view>
</extension>


The class that is now referenced in the extension instead of the view itself is the spring extension factory followed by a colon and the id of our bean from the spring context. The rest of the extension definition looks exactly as before (without the extension factory).

The Spring Extension Factory includes two additional options to refer to the bean id within the extension definition. This is the strategy that I implemented into the extension factory:

  1. If a bean-id is explicitly defined (like in the example above), use this id to lookup the bean.

  2. If not, search for an id attribute within the contribution element of the extension and use it as the bean-id.

  3. If no id attribute is found inside the contribution element, try to use the id of the extension itself as bean-id.


The first option is the most explicit one. The second option works just for those extension definitions where the corresponding extension point schema defines an id attribute as part of the specific extension (this is the case for views, but obviously not for all extension points). The third option can be used for all extension points but is less explicit that the first one. In the end its a matter of taste which option you prefer.

Comments, feedback and improvements, of course, highly welcome.

Have fun with it!!!

Equinox Aspects and Spring-DM at the OSGi-Community-Event 2008

The OSGi-Community-Event 2008 in Berlin is less than two weeks ahead and I am pretty excited to give a talk on Spring Dynamic Modules there as well as some live demos on Equinox Aspects at the evening reception Tuesday night. The talk on Spring-DM will introduce the possibilities of using the Spring framework and Spring-DM within the OSGi world using some examples and live code. For the evening demo of Equinox Aspects I will do my very best to show the current state of Equinox Aspects together with some cool new features things like dynamics (aspects coming and going) with Equinox Aspects and (maybe) even load-time aspect weaving for Spring and Spring-DM within OSGi using Equinox Aspects. So please keep your fingers crossed for my live demos. :-)

Saturday, May 10, 2008

Finally aspects become dynamic

I recently committed some changes to the Equinox Aspects project which allows the Equinox Aspects runtime to handle dynamically uninstalled aspects correctly with regards to the woven bundles in the system. Having this it was only a small step to also deal with dynamic updates to aspect bundles as well as woven bundles at runtime. And now, finally, we are there: real dynamics for aspects. You can install, update and uninstall aspects at runtime as you like and the Equinox Aspects runtime takes care that everything will be woven and re-woven correctly. This is really really cool and a huge step towards real OSGi-enabled AOP, I think.

But what happens if aspect bundles are installed, updated or uninstalled at runtime? All other bundles that need to be woven, that need to be re-woven or that need to be un-woven from the aspect are updated automatically by the aspect runtime using the OSGi mechanisms. This means also that your system should be able to deal with OSGi dynamics and bundles coming and going (which is not a trivial thing to do). So be a good citizen of the OSGi world and your bundles will behave well when aspects are coming and going at runtime... :-)

Thursday, May 01, 2008

Aspect Weaving for OSGi at Java Forum Stuttgart

This years Java-Forum-Stuttgart 2008 is on the 3rd of July and takes place again at the Kultur- & Kongresszentrum Liederhalle (KKL) in Stuttgart, Germany. I attended this nice conference over the past years talking about various topics and listened to interesting talks there. Its well organized and its a pleasure to be there.
This year I will talk about one of my favorite topics: Aspect Weaving in OSGi. I will tell people what they need if they are going to adopt OSGi and AOP for the same system and how it is possible to modularize aspects into OSGi bundles. The talk will contain some live demos showing load-time aspect weaving for OSGi using the Equinox Aspects open-source project. It will be way cool, don't miss it! :-)

Saturday, April 26, 2008

When all is said and done I become a Guru ;-)

While reading the OSGi book from my colleagues I stopped by the dedication section on the first pages and found that Matthias dedicated the book not only to his wife and his daughter but also say thanks to me in this section, calling me his "personal Equinox Guru". Wow, I finally become a Guru... ;-)

Aside from not feeling like a guru at all and aside from the fact that there are hundreds or even thousands of developers on the planet knowing more about Equinox than I do - I feel somewhat proud to be mentioned in this book in such a nice way. :-)

Thank you, Matthias!

German OSGi Book

Colleagues and friends of mine have published a great introductory book on OSGi. Its called "Die OSGi Service Platform -Eine Einführung mit Eclipse Equinox". Its completely written in German (but don't be afraid, they told me an English version is somewhere in the pipe) and the first book on OSGi on the planet. Wow. Make sure you get a copy and learn about OSGi. I can just highly recommend to read this great book!

Friday, April 25, 2008

Slides from JAX 2008 Talks Available

So I am back from the JAX 2008 conference where I met people, gave a number of talks and listened to some other interesting presentations. The PDF versions of my slides are now available from the events section. Enjoy!

Wednesday, March 26, 2008

Update: Getting Hooked on Equinox - Article in German Eclipse-Magazine

I complied with the term of the publishing company not to publish the PDF file of my latest article on the hook mechanisms of the Equinox OSGi runtime for a certain period of time, but the waiting time is now over. I put the PDF of the latest article on "Getting Hooked on Equinox" (in German) for the German Eclipse Magazin online in the publications section. Enjoy!

EclipseCon 2008: Short Talk on Adopting "The Eclipse Way"

I put my slides from my short talk at EclipseCon 2008 about adopting "The Eclipse Way" online in the events section. Enjoy!

Tuesday, March 18, 2008

Dependency Injection for Extensions

While preparing the tutorial on Spring Dynamic Modules for this years EclipseCon I played a bit with using Spring Dynamic Modules to dependency inject beans into views or other stuff I typically define as extensions for my Eclipse Rich Client Platform application. The problem is that the actual objects for those extensions are created by the Extension Registry and do therefore not pass the spring context for dependency injection. I needed to find a way to combine those two technologies somehow.

I came up with a very small and trivial solution for this: I created a class called SpringExtensionFactory that implements IExecutableExtensionFactory from the Extension Registry mechanism. This extension factory takes an ID from the extension definition, finds the spring application context for the bundle that contributes the extension and tries to retrieve the spring bean with the same id from that application context. This bean is then returned as the extension object. This trivial solution does not require any additional programming work to be done, no load-time weaving (for @Configurable, for example), just plain nothing.

Yon can download this SpringExtensionFactory from here, its open-source under EPL 1.0:
The interesting question is which ID this extension factory takes from the extension definition to look up the bean in the application context. The answer is: It is a two-step process. It first tries to find an "id" attribute within the configuration element of the extension definition. This is typically the case for RCP views, for example. They have an "id" attribute to identify the view. If there is no "id" attribute found within the configuration element it steps back to the extension definition itself and takes the "id" attribute from there.

If you have any questions I am happy to help you with this stuff. Just leave a comment (to share your thoughts and questions with the community).

EclipseCon 2008: Tutorial on Spring Dynamic Modules

EclipseCon 2008 has started today in sunny Santa Clara. I ran a two-hour tutorial about Spring Dynamic Modules together with Adrian Colyer from SpringSource and BJ Hargrave from IBM. The tutorial went well and was full-packed with a lot of stuff that we showed and demoed (mostly Adrian). Therefore it was no real surprise that we completely ran out of time and that my final part on Eclipse RCP and Spring Dynamic Modules was mostly skipped. Nevertheless you have the chance to take a look at the slides, they are online at the conference site as well as on my events section.

Thursday, March 13, 2008

Release 1.1.0 of Equinox Aspects available

I am proud to announce that a new release of Equinox Incubator Aspects is available for download. Version 1.1.0 features a standard caching service for woven bundles on non-IBM VMs (contributed by Heiko Seeberger) and contains a number of big fixes and minor improvements.
Especially interesting is that you no longer need to define aspect bundles upfront in the config.ini when you start your runtime. The reworked supplementing mechanism can deal with such situations and handles even dynamically installed aspect bundles correctly (more details to follow in this blog).
This release works with all up-to-date and development versions of AJDT (1.5.1, 1.5.2, 1.6.0) and Eclipse (3.3, 3.4).

Monday, February 25, 2008

Getting Hooked on Equinox: Article in German Eclipse-Magazine

The current issue of the German Eclipse-Magazin publishes an article that I wrote together with Heiko Seeberger vom Metafinanz: Getting Hooked on Equinox. The article describes the adapter hook mechanism that is part of the Equinox OSGi implementation. Using this mechanism you can easily modify the behavior of the Equinox runtime or add additional features to it. This mechanism gives you a lot of power over the Equinox implementation without modifying the original code. And that means you can deploy your additions as separate bundles. Users don't need to manually install a modified osgi implementation!!!
I am using this mechanism for the equinox aspects incubator project to add load-time aspect weaving to the OSGi runtime. The article describes the basics of the mechanisms, who it can be used, and gives some examples where it is already being used.

Sunday, February 24, 2008

GetTogether 2008 Event from Software Engineering Radio

The se-radio team is going to be hosting a small conference called GetTogether 2008 in the fall of 2008. The conference will be in the open-space style, so its focussed on interesting discussions rather than formal paper presentations. Nevertheless in order to participate you need to submit a small position paper describing a topic to discuss at the event. Maybe some interesting keynotes will be at the conference as well. Thanks a lot to Markus Völter for doing a great job in organizing most (if not all) of this stuff.

Monday, February 18, 2008

The New Allianz Business System uses OSGi and Equinox Aspects

I picked up some really cool news: the german newspaper Computerwoche reports about the Allianz (the huge insurance company) is moving their complete IT to a new system called Allianz Business System. The article says that the new highly integrated system is based on Eclipse and OSGi technology. Wow! But its comes even better: They are using Equinox Aspects inside, the tiny little incubator project I am working on to integrate aspect weaving into the Equinox OSGi implementation (as you can read from this talk at the upcoming Eclipse Forum Europe).

Friday, January 25, 2008

Slides from OOP

Yesterday I gave a talk at the OOP conference together with Ivo Eitner, the technical project manager of a project I am involved in as a consultant over the past years. We talked about our experiences adopting "The Eclipse Way" within that project. If you are interested in the slides and are able to read and understand German, here are the slides as PDF.

JAX and Eclipse Forum Europe 2008

Seems like they added some more parts to the program of the JAX 2008 conference together with the Eclipse Forum Europe 2008. And I am happy to see that some of my sessions got accepted. :-)

Saturday, January 19, 2008

Recording of SpringOne Talk on Spring and Eclipse RCP

A complete video recording of the talk about Spring and Eclipse RCP that I gave at last years Spring One conference is now online at Parleys.com. Thank you guys for all the great work of recording all the sessions!!!

Saturday, January 12, 2008

New Release of Equinox Aspects

After a long period of quiet I started to work in Equinox Aspects again and fixed two bugs in the current implementation. The new release is available from the Equinox Incubator Aspects website. In general the project is about an OSGi extension that adds load-time aspect weaving to the Equinox OSGi implementation. By doing that you can modularize aspects in OSGi bundles. The runtime takes care that your aspects are woven into the system at load-time.