Saturday, September 17, 2005

BPEL explained

BPEL is an important language for the process-oriented approach to SOA. Because BPEL has been designed specifically for definition of business processes it provides good support for various specifics of business processes such as support for long running transactions, compensation, event management, correlation, etc. BPEL is well suited for use with the J2EE platform and many BPEL servers build on top of J2EE. With ideas of combing BPEL and Java (BPELJ), and WSIF, the usability of BPEL is even increasing. We should also look at the emerging JBI (Java Business Integration) specification aka JSR 208 which will give business integration and BPEL an even better documented position in the Java platform.

rating comment: I've read a couple of articles about BEPEL, and I must say that this one is the best so far. It answered all my questions which emerged while reading the other articles. Although I don't have any practical experience with BEPEL whatsoever, I think it's an important approach in order to build a SOA.

Wednesday, September 14, 2005;

Google hat eine spezielle Suche für Blog-Inhalte gestartet, um das Finden von Blogs im Internet zu vereinfachen. Suchergebnislisten stehen als RSS- und Atom-Feeds bereit, um sich über Neueinträge zu bestimmten Themen auf dem Laufenden zu halten. Wie bei Google üblich befindet sich die Blog-Suche derzeit noch im Beta-Test.

Monday, September 12, 2005

Unit Testing Rules

A test is not a unit test if:

  • It talks to the database It communicates across the network
  • It touches the file system
  • It can't run at the same time as any of your other unit tests
  • You have to do special things to your environment (such as editing config files) to run it. 

Tests that do these things aren't bad. Often they are worth writing, and they can be written in a unit test harness. However, it is important to be able to separate them from true unit tests so that we can keep a set of tests that we can run fast whenever we make our changes.

I agree in that unit tests should be completely independent of their environment. I also agree in that you should rather use mock objects instead of e.g. a database. What I don't agree on is that it's supposed to be a bad thing to change your environment to be able to run a test. Let's say you run unit tests for a persistence component, why is it a bad thing to change the persistence implementation, so that mock objects are being used, before running the tests? If you are using  an automated tool, it can be done transparently, without any manual changes needed.

Friday, September 9, 2005

Programmers' personality

.. something that I've noticed when I interact with other programmers. It should come as no surprise that the personality profile for programmers is not the same as that of the population at large. In fact, I feel that when I arrive in an airport for a software conference, I can usually just "tell" whether another person I see walking by is there for the conference or not. We're a weird bunch..

I am glad, that I am not the only one feeling this way ;-) 

Thursday, September 8, 2005

Ebay will sich Skype ersteigern

EBay will eventuell den VoIP-Anbieter Skype übernehmen, berichtet das Wall Street Journal. Gespräche bezüglich einer Übernahme seien angeblich derzeit am Laufen. Der Kaufpreis für Skype soll zwischen 2 und 3 Milliarden US-Dollar liegen. Für eBay wäre dies allerdings mit einem deutlichen Strategiewechsel verbunden.

Für eBay ist die VoIP-Branche doch komplettes Neuland, oder irre ich mich da? Naja mal abwarten, vielleicht ist ja auch gar nichts dran... 

Wednesday, September 7, 2005


Just as design patterns provide a way to communicate concisely about desired software practices, antipatterns provide the equivalent advantages for communicating undesirable practices—and here's a set of common antipatterns to get you started.

rating comment: The article is okay, but sketchy and not very detailed. I would have liked to read a more profound article, maybe with less antipatterns, but a more detaileddescription . Nevertheless it's an article worth reading, since it gives you a good idea of what antipatterns are and where to look for them. By the way, after reading this article I have the feeling that Java EE is a great template for antipatterns and a place you definitely should check out when looking for them.

Monday, September 5, 2005


JDBC 4 is the forthcoming release of the Java Database Connectivity API. Currently in Early Draft Review in the JCP (JSR 221), JDBC 4 is a major new release with a strong focus on ease-of-use and programmer productivity. The new JDBC version also introduces support for SQL 2003 data types, including SQL's native XML type. This article surveys the key JDBC 4 features.

rating comment: Great article, giving a good overview of some new features of JBDC 4. I really like the type-safe queries, cause sometimes a fully blown O/R mapping framework is just too much. If you only need a couple of statements, the type-safe queries are a nice alternative.

Thursday, September 1, 2005

Controversial Thoughts on Java

I've just finished reading "Java Puzzlers: Traps, Pitfalls, and Corner Cases" by Joshua Bloch and Neal Gafter (Addison Wesley, 2005). This is a collection of small, often simple examples that produce (usually) surprising results, along with an appendix of guidelines produced by examining the puzzles. Both authors were part of the core Java development team at Sun, right up until the release of J2SE5, when both of them left for Google.

One of the most interesting aspects of the book is what these two, who are about as close to the center of the Java universe as you can get, quietly said at the end of some of the puzzle solutions, in their "lessons for language designers." Which is to say, "if you are designing your own language, here's something you should do instead of what Java did." Which is to say "where Java didn't get it right," in the gentlest possible terms.

I really like this weblog, cause it points out very interesting thoughts, which I mostly agree on. He says:  Java has obviously moved the programming world forward, but I think its major wart has been the inability of the adherents to look at Java objectively. I totally agree on that, especially when it comes to the Java vs. .NET war! He also mentions the Java community, which he thinks tends to stifle problems and questions, when it comes to Java's design. I only agree on that partially, cause I think Java developers are quite honest when it comes to the design (and the flaws that comes with it) of their software. Well anyways, I'm thinking of getting the book, cause it sounds quite interesting.