Today I have come across a nasty bug in mysql cursor. It apeard in a method that i used for ages. Usually iterating through the cursor in mysql is based on defining a "continue handler" which gives a signal that a fetch from cursor is empty. Unfortunately it turns out that this method does not always work, because the continue handler is triggered not only when there is an empty fetch. In my case the cursor made only 2 loops instead of 40.

A problem with seam-gen and mysql? Simple types instead of @ManyToOne or @OneToMany realtions. If you are using Eclipse in this article you may find the reason of this problem.

GWT applications sometimes are a bit heavy in terms of bandwidth usage; because they go over 300KBs, which is too much for some users. Fortunately there are several things that can be done to reduce the size. First technique really kicks a**.

DbSchema [Free] database tool

Infosystem is a satisfied user of DB Schema, it has our full recommendation.

Servlet generating an Excel file

For those, who are in a hurry, code of the servlet is at the end of the article. In my online forms composer I wanted to add a nice functionality - export of collected data to excel file. Everything has gone smoothly, but… There is always a “but”. Everything was ok on my development machine (Windows), but failed to work on my production server, which runs on linux (Gentoo to be precise).

How to restart a JBoss application, without restarting server.

I realy like jboss seam and recaptcha project, so it was natural for me to use both technologies. It turned out that integrating them is as easy as breathing. To achieve my goal I have made following steps:

I will describe my way to install the JBoss server on Gentoo. My knowledge of UNIX is average, term which would describe me relations with Linux is “Coitus interruptus”. Gentoo proved to be a little more demanding than other distributions.

Serwis formularze.eu tworzyłem przy pomocy Google Web Toolkit. Po jakimś czasie postanowiłem, żeby moja aplikacja była dostępna w innych językach. Framework Google’a po raz kolejny miło mnie zaskoczył, bowiem dostarczał całkiem przyjazne i proste rozwiązanie dla tej kwestii.
W tym artykule pokażę jak wykorzystać mechanizm internacjonalizacji w GWT przy pomocy Eclipse (z zainstalowanym plugin’em GWT). Zakładam u czytelnika znajomość Javy i technologii GWT. Koniecznie jest też zainstalowane GWT SDK oraz dodane go do zmiennej PATH (dla użytkowników Windows).