Monday, November 19, 2012

Thymeleaf & Magnolia: a prototype

I've been working with magnolia for a while now, and I tend to like it's simplicity. But I don't like freemarker and even less JSP's. So I tried to integrate thymeleaf with magnolia, which wasn't as straightforward as expected.

Magnolias rendering engine API is based on working on a character stream for creating it's output. It does so when including areas & components, which didn't work wout with thymeleaf, that does includes based on it's internal DOM representation. So what I've created by now is a little hackish, I started with thymeleaf's include processor and mimik'ed the spring controller invocation from blossom and provided the magnolia content/context objects locally to the dom for rendering.

I had to clone some code fragments from magnolia and spring (cruel final and private api), but it's working like a charm.

You can find the code on github, should be a good starting point if you want to use thymeleaf with magnolia.



Sunday, October 7, 2012

RAP, OSGi & HibernateSearch Infinispan Cluster

Whilst trying to setup hibernate search on an infinspan cluster for my RAP application I came accross another "hibernate doesn't like osgi" oddity.

The JMS setup for hibernate search is configured through JNDI. That wouldn't be a problem when running deployed on my tomcat instances, but how should this work in my develepment setup, where I use the RAP tooling and run on the embedded jetty http service? No JNDI there.

So I created a replacement for the JMSBackendprocessor from Hibernate Search, that looks up the jms connection through means of OSGi. Bye bye good old JNDI, never liked you either.

Now if I only had a failover for the workbench...

Thursday, September 6, 2012

Back from #mconf12 in Basel

I spent Tuesday and Wedensday attending this years magnolia conference in Basel. It was a rather small event, and it brought me some nice insights about how others solve things in magnolia, what problems other have and what crazy ideas come around sometimes. The most crazy ideas in my eyes came from Kimmo Björnsson and Åke Argéus, two guys from sweden, who integrated magnolia as a grails plugin. This is true spirit, guys. Tuesday evening we met at the magnolia headquarters, those magnolia guys know how to party!

Saturday, August 11, 2012

Eclipse RAP UI Testing cont'd

I made some progress with my UI testing efforts for the RAP port of eiswind book publishing software.

The obvious thing is that we can set ids on widgets by setting a widget id:
b1.setData( WidgetUtil.CUSTOM_WIDGET_ID, "myButton" );
The next step is a little hackish, but works for me: I reuse the contribution item ids from the workbench as widget ids (snippet from

With some help from the rap people I finally even got ids on table row items (Snippet from TreeRowContainer.js)

Have fun now:)

Sunday, July 29, 2012

From Hibernate to MongoDB - Part II

For those who are interested, I still don't have any large dataset results.
Last weekend I spent with datanucleus/mongo but I had some issues that noone did seriously take care of, so I decided better not to go that way (Sorry datanucleus folks, but I'm used to get support from the community). This weekend of course I started another approach with eclipselink which has jpa/mongo support, too.

Let me say, it was a whole lot more work than I expected it to be. EclipseLink has a different understanding of the JPA annotations, which caused some boring refactorings in the domain model. Mostly Fetch.Eager doesn't work with mongodb, and some other minor stuff, I found that ManyToOne(optional=false) doesn't work either, have a bugzilla for this one.

But the hardest work was making eclipselink play with spring dm, and gemini jpa. I had some issues with the latest spring release aop stuff, which didn't play with the osgi classloading anymore, so I went back to 3.0.5 which I knew was working. Then I created a FactoryBean based on the gemini jpa EntityManagerFactoryBuilder service, so that I can still use my spring managed transactions.

One word to the gemini folks: Bundle start order is not what osgi suggests. But restarting a blueprint/spring powered bundle (thats what gemini jpa does for weaving the entity classes) when their appContext isn't finished yet gives you an explosion of exceptions. By the way I am still running on dm 1.2 because of the namespace handler resolving still is a mess in blueprint. Just my two cents.

Inbetween I did some clean up work (pay your debts) that still needs some polisihing, as there was not enough time to pull through all the changes, so there are some compile errors now. But nothing evil.

One thing to say is that I have some logic that needs a complete restructruring, as there were many queries based on the relational thinking, that now don't work anymore, as eclipselink/mongo doesn't support joining. Even if it did, mongodb gives you a different persistence model and it makes sense to work with larger objects than I did with the relational model.

I have created plenty of tasks that still need to be done, I'm far away from starting to implement mutli-tenancy (which of course is the reason for all of that).

Up to now I spent round about 40hours on this (remember domain model is about 70 classes, that are fine now). Of my 20 DAO classes there are three left to restructure that depended too heavily on the relational stuff. All other stuff is working.

Load time is blazing fast now, most of the time goes into RAP UI code creating the editors. Guess this will be my new bottleneck :)

My overall impression is, that this is still young stuff. Speaking about eclipselink/mongo, most important things work, but things that don't, always throw completely insane errors, forcing you to debug into the code to understand what has gone wrong. For e.g. when there's a join in the query, a ClassCastException is thrown, that DatabasePlatform cannot be cast to MongoPlatform. eclipselink folks, there is plenty of work in there, too. But overall I am confident today that I can build my (non-profit:) business on it.

Saturday, July 28, 2012

RAP UI Testing

These days I'm evaluating UI testing methods for RAP Applications. I made some nice progress with a commercial tool called QF-Test. It has a click recording functionality, and works like a charm with the WidgetUtil.CUSTOM_WIDGET_ID way that rap offers to generate custom ids for the controls. It's really easy to setup, and seems to have no problems with the rap ui so far. I allows groovy/jython scripting and is able to evaluate JavaScript expressions on the dom under test. I am really happy that I finally can get up some ui tests quite easily. Plus I have to say that the folks at QF-Test took great care of getting me started with my evaluation license, +1 for their support.

This screenshot of a recorded Sequence is german, but it should be understandable (Klick means Click :)

Sunday, July 22, 2012

From Hibernate to MongoDB - The promise of changing the persistence layer.

This is not basically eclipse related, but it comes from my eclipse project, that I recently ported to RAP and now I plan to go multi-tenant with it.

This is not my first attempt in this direction, but this weekend I have a working proof of concept for changing my persistence layer from hibernate/hibernate search to mongodb.

I have about 80 domain classes and a bunch of handmade custom DAOs that are mostly based on the JPA Api. After playing with orientDB (I stopped that because of no "delete-orphan" there) this weekend I made an attempt with the datanucleus mongodb storage engine. To replace hibernate search, I decided to go for elasticsearch, which seems to be straightforward to build a multi-tenant index.

At first I struggled with some classloading issues, the datanucleus enhanced classes need a dependency on the jdo api at runtime. Then one major all-solution refactoring to use the mongodb string-based id on all my entities. I guess that took most of the time. I also changed  many dependend relations to embedded types, so that I can get the performance benefits mongo db promises.

Before I had load times for a single object graph (hibernate/sql server) from 3 to 4 seconds (yes one entity, you now know why I have to change that) and with mongo db and all the embedded collections you can hardly notice load time.

It's just that the relational model is not suited for complex object graphs. Even with massive parallel processing on an sql server cluster I had processing times around 10 minutes for 50k objects. I do not have values on that for mongo (need an importer first), but I guess it will work out.

I still have some exceptions and need to refine the elasticsearch integration, but over all I worked some 15 hours on it and at least I have a proof that it's doable.

Monday, February 27, 2012

Playing with RAP 1.5

Last weekend I started to try my RCP based app on a RAP1.5 target platform. Of sure I had to make some changes, most annoyingly I had millions of toolkit.paintBordersFor that isn't implemented in RAP. I could make the Nebula Gallery widget work with some restrictions. I still have some headache with the CkEditor integration as the RAP Browser does no Events. But I think with some hints from the community I can make this out. It started quite as an experiment, but after some 20 hours I now can get a feeling that I can make everything work.

Sunday, February 19, 2012

VAADIN and mod_proxy

Yesterday I tried to deploy a beta relase of my new Vaadin application on my debian box. I'm running it on an embedded jetty 6.x that I needed to get proxied by my apache web server. I found several posts about how to do this, and explanations that the VAADIN servlet has some troubles with beeing behind a proxy. The app on jetty on my side is running on localhost:8889/shop. It looks quite strange to me, but it works. I needed the /APP/ config to make StreamResources work. The proxy configuration that finally worked goes like this:

<VirtualHost *:80>
  ProxyPass /VAADIN/
  ProxyPass /APP/
  ProxyPass /
  ProxyPreserveHost On
  # Local reverse proxy authorization override
  # Most unix distribution deny proxy by default (ie /etc/apache2/mods-enabled/proxy.conf in Ubuntu)
  <Proxy *>
    Order deny,allow
    Allow from all

Tuesday, January 24, 2012

Rich Text Editor for Eclipse/SWT

I have been looking around, but a feasible Rich Text Editor for SWT seems to be hard to find.

Edit: 2013/06/15: As of today you should look at the eclipsesource example for RAP 2.0. It should give you a good starting point. 

Followup from 2012/3/12: I just modified the ckeditor example from
to include a server-side ready and dirty event. That's all I need.