Monday, August 22, 2005

Google Desktop Sidebar

Von der Windows-Desktop-Suche Google Desktop Search wurde eine neue Version veröffentlicht, die vorerst nur als Beta-Version zur Verfügung steht und nun mit einer Sidebar ausgestattet ist, die einen Infobereich links oder rechts auf dem Bildschirmbereich anzeigt. Die Sidebar informiert etwa über neue Nachrichten, aktuelle Aktienkurse, frisch eingetroffene E-Mails oder gibt einen Wetterausblick und kann noch einiges mehr.

Bin gespannt ob das neue Feature der Suche was taugt! Viel interessanter finde ich eigentlich das Gerücht, dass Google ins IM Geschäft einsteigen will, denn das wäre nun wirklich mal nen Kracher! 

Sunday, August 21, 2005

DAO Example

A couple of days ago I read an article about the Apache Ibatis DAO framework, which got me very interested. I decided to code a small example to get a closer look at the framework.

I use nearly the same domain logic as in the drools example, which is excellent to implement my "Liquor Store Example".... Anyways, I decided to use Apache Ibatis DataMapper, as an O/R-Mapping framework. Both frameworks I use here are Ibatis products, which lets them work perfectly together. Since everything comes from Apache nowadays, I thought Derby, the embedded database engine, is a good choice for a database.

So what does my example do? It implements a simple store application, which I like to call "Liquor Store". As I said, it is kept very simple. I just use a couple of domain classes to get an idea of how things could work in a real application. To get a closer look at the DAO framework, I decided to store the data of two domain objects persistently, for example the data of the "Item" domain object. I use the DAO framework, to manage the data in a persistent store, which is in my case the Derby database. For further information how things work, check out the readme file of the example.

Both frameworks, DAO and DataMapper, left a throughout positive mark! They are well documented with examples and an easy to read manual, which is sometimes a major setback when using free software. Using the DAO framework is very straightfoward and in conjunction with DataMapper very efficient. The configuration of Apache Ibatis DAO is quite simple, you just have to define the persistence mapping mechanism, in my case DataMapper, and the DAO Implementations which are being used to store the data. Configuring Apache Ibatis DataMapper is also very simple, there is one confguration file to define the database that you want to store your data to and for every persistent object there is another file which defines the mapping. The configuration part was the most time consuming task when I was developing this example. I hope there is tool support for configuration out there, which would speed things up. Programming with DAO is very straightforward, since you are programming to interfaces. This makes it easy to test your business logic with mock objects.

All things considered, I think these two frameworks are very useful and they are worth taking a look at.  

WP Plugin suggest version 0.6

This is just a maintenance release, nothing has really changed. I updated the readme file and tested the plug-in in detail. I found a couple of issues, which I am working on.

There are still small problems when using Internet Explorer, with my template they are pretty ugly though. There is also a new issue when using Firefox, which causes a lot of spacing at the bottom of my page. Altogether I am quite surprised that he plug-in works so well with WP 1.5. So I think I can anncounce WordPress 1.5 support from now on.

The latest version, which is 0.6 (I didn't do a 0.5.1, cause I wanna keep it simple), can be found at my download site or at the wp-plugins.org repository.

Saturday, August 20, 2005

Neues Blog, Neues Glück

Nachdem mein Blog vor zwei Tagen gehackt wurde, habe ich mich entschlossen auf Wordpress 1.5 umzusteigen. Da ich diese schon einmal probiert hatte, wusste ich was auf mich zukommen wird.

Der Hack fand in der Nacht von Mittwoch auf Donnerstag statt. Soweit ich das nachvollziehen kann, haben die Angreifer eine Sicherheitslücke in Wordpress 1.2 ausgenutzt, was mich dann doch zu einem Update bewegt hat. Die verwundbare Datei hat übrigens mit der Trackback-Funktion von Wordpess zu tun, die ich ja wenige Stunden zu vor gefixt hatte.

Da ich schon einmal versucht hatte auf eine neue Version von WP umzusteigen, wusste ich, dass mein Template nicht mehr funktionstüchtig sein wird. Nach einem kurzen Test hat sich dies bestätigt. Also habe ich mich entschlossen meinen Blog in ein neues Gewand zu hüllen. Das Template war im Originalzustand schon sehr hübsch anzusehen, allerdings habe ich dann doch jede Menge Anpassungen vornehmen müssen, um aus dem Gewand einen Minirock mit High Heels zu machen. Das Ergebnis kann sich meiner Meinung nach sehen lassen, auch wenn es ein wenig gewöhnungsbedürftig ist.

Was mich erstaunt hat: Meine beiden Plug-ins sind ohne größeres Customizing mit WP 1.5 einsatzfähig. Dazu gibts aber später mehr...  

Wednesday, August 17, 2005

Trackback gefixt

Nachdem ich festgestellt habe, dass das Trackback nicht mehr funktioniert, habe ich es gestern gefixt.

Aus irgendwelchen Gründen, hängt wohl mit den "Rewrite Rules" zusammen die ich definiert habe, hat die Trackback-Funktion nicht mehr funktioniert. Naja, jedenfalls hat sich jetzt auch die Syntax der Trackback-Url geändert, was manchmal zu Problemen beim Layout führt, nämlich dann, wenn die Url zu lang ist.

Mal sehen was man da noch machen kann, vielleicht findet sich noch ein Weg die Url zu kürzen.

Introduction to JDO

The Java Data Objects (JDO) specification, Java Specification Request (JSR) 12, defines an API for a standard way to transparently persist plain Java technology object and database access. Using JDO, Java application developers can write code to access the underlying data store without using any database-specific code. This article provides a tutorial on JDO. It covers the essentials of JDO and offers sample code to give a flavor of the effort involved in using JDO to persist your Java technology objects.

rating comment: Very good introduction to JDO, which grasps almost every aspect of the technology. Although it only scratches the surface, I like this article a lot, cause it gives a good overview. A couple of month ago I played around with the JPOX JDO implementation, but I couldn't get it to work smoothly, which somehow left a bad impression on me. Well, I might give it another shot, though I personally think the new EJB 3.0 persistence specification could be also worth looking at.

Tuesday, August 16, 2005

Apache iBatis DAO

The J2EE Data Access Object pattern calls for encapsulating access to a data source behind an API, giving you the freedom to change implementations or use different persistence strategies for different operations. As Sunil Patil shows, the Apache iBatis DAO framework helps you develop such a strategy.

rating comment: Great article which gives a solid introduction to DAO and the Apache iBatis DAO framework. The notion of DAO is not new to me, but this framework seems to be very cool! I like the implicit transaction and connection management, this could be really helpful. I hope I can check out the framework soon to get a closer look, cause it really got me intrigued.