PROMATIS wants to reach a technically leading role on the market in all fields of business activities. Guarantors of success are among others our highly qualified Technology Specialists and our lived Knowledge Management System. Our Specialists would gladly share their know-how with customers and partners. Here we will post our current Blog-Entries irregularly and allow thereby for a deep insight into our Development Labs.

21 December 2006

‘The tedious XML-Validation” or ‘From a developer’s daily life and suffering”

Once upon a time there was a project with the requirement to validate sundry XML-data against their corresponding XML-schemata. ‘Nothing easier than that!” is what was thought, as one had previously worked successfully with the Apache Xerces. Thereby at the same time a category for the internal PROMATIS Middleware Components (PMC) was created, which was intended to ease the handling of the Xerces-Parser for our work.
Well, go at it! The corresponding categories and methods were soon completed and were tested in Oracle JDeveloper independent from the rest of the project. Everything worked just fine, and the else wise sorely afflicted developer seemed at one with the world.
But then the shock! After bringing in the validation categories into the existing project all of a sudden nothing worked anymore. The web application, for which by the way Java Server Faces was used, couldn’t be started anymore by hook or by crook. But since several developers were working on the project, the culprit couldn’t be made out immediately. Ludicrous problem reports came up, which the expert associated with the Java Server Faces, but not with the Apache Xerces.
After long and nerve-wracking research we found out that the Application Server OC4J automatically used by JDeveloper, which was also used in this project to test the application, usually uses the Oracle-own Oracle V2-Parser to parse XML-Data. The application of other parsers is not recommended. That’s what Oracle says. No word about nothing working anymore at all. In any case, when starting Java Server Faces-Applications, different XML-Data (day-libraries, faces-config ...) have to be parsed as well. So if there’s a different parser in the classification path, the OC4J can’t handle it anymore and a Java Server Faces error report pops up, which then again has nothing to do with JSF.

18 May 2006

Oh gee! We just had the developer’s typical worst case scenario: the boss came in, smilin' from one ear to the other, carrying his laptop under his arm and announced that he needed "some stuff" on it - of course until tomorrow! "Some stuff" was Oracle 10g Database, Oracle Application Express and a "few" repositories with a bunch on data in ‘em. He wanted to take the laptop to a customer so he could show it off. I mean this guy has got some nerves… This was a task that usually takes more than just a day to be accomplished!

Lucky us, we use VMWare here. We hooked up the USB-plate, a virtual machine that already can do everything, copied everything over to the laptop and started it. Hmmm, now that did NOT quite work yet. It actually already swapped when we tried to boot. And besides that, it needed way too many steps to get started in the first place - definitely nothing our big boss can handle!

So we scaled down the SGA Database, the SGA of the Database never even started the Enterprise Manager (which our boss can't handle anyways :-) ), adjusted the booting script, copied it into /etc/rc.d, made sure it started automatically with chkconfig and also shut down automatically. We set the initial run level on 3, placed an icon on the desktop so that a simple double-click would open up the VM and start the procedure automatically. To top it off, we configured NAT so that everything was accessible via Windows, and also some Port Forwardings for HTTP-Server and SQLNet. But hey: it still didn't run…

But then it hit us: the XP-Firewall! It still needed some defining concerning exceptions. And there you go! Everything went smooth… Effectively the boss came in after his appointment, all happy and stuff that everything went well. Of course nobody even bothered to honor the job or the know-how it took to get it done… :-(

M.P.

24 April 2006

Testing-Experience with the new Development Platform Ubuntu JEE

Who does not look for alternatives to established Windows-Development Environments? In our Labs we have made first tests under Ubuntu Linux Version 5.10 and I’ve got to say: It’s banging!

Thanks to the platform-independence of Java-Technologies we were able to build up a complete Oracle JEE-Development Platform. To do so, we installed the Oracle JDeveloper 10.1.3 in its Studio Edition incl. ADF onto JDK 1.5. But, as life plays, we first had to draw on the newest Sun Java SDK. Worse luck, there’s no standard procedure for this task under Ubuntu. L So, back to dash and get those two additional repositories (among others ubuntu.tower-net.de/ubuntu/ breezy java) bound into that Ubuntu Distribution, which is based on Debian, before the packages can be installed.

We use the Subversion for Source Control Management (SCM) in our Labs. And sure enough we don’t want to miss that under Linux! So we also installed the Subversion 1.3 under Ubuntu. Thanks to disposable JDeveloper SCM Extensions we were able to access the company-internal Repository with jsvn 0.8.

Now it’s time to pull up those sleeves and to realize the link-up to the internal Apache Maven Repository and to weave in the Oracle SQL Developer as well – supported by our huge wisdom (speaking modestly ;-) ). When it’s all done I’m sure it’ll be a ball. I’d even bet my boss on that for the next round of Latte Macchiato at the café.

R.S.