Sonar “Close Connection” warning workaround.

When you use Spring and Ibatis and SQLTemplates, you could have code in your project which looks somewhat like this:

Connection connection = DataSourceUtils.getConnection(getDataSource());
...<do connection stuff here>...
DataSourceUtils.releaseConnection(connection, getDataSource());

Sonar will report that you did not close the connection, while in fact, Spring did that for you. You can not just add a “connection.close()” to the code because the whole point of calling “releaseConnection()” is to have Spring handle all the smart stuff on committing, closing, and returning the connection to the pool if needed.

In our company, not closing the connection is a major blocking violation (and it should be). But in this case, there is no way to make the Jedi wave to Sonar, telling it that “this code will do just fine”. So I added the following trick, albeit a bit dirty:

if (connection.isClosed()){
   // This code is only here to keep Sonar from
   // warning us that the connection is not
   // closed. Please note: Do not just close an
   // unclosed connection, Spring should handle
   // connection closing and returning to the pool.
   connection.close();
}

Use it to your advantage, but use this responsibly. If you see any problems in my solution, or if there is a better way to do this I’d be happy to hear about it.

Eclipse 3.4.1, OSX and Java 1.6

I recently downloaded Eclipse 3.4.1 for Mac OSX, and tried starting it using the eclipse.app icon. It did not work, and I noticed a message in /var/log/system.log telling me that the JVM could not be loaded.

J-Fall 2008

Last wednesday I was at J-Fall 2008, a fairly large event for Java programmers in the Netherlands. This event is organized by NLJUG. You can read some of my notes on the different sessions in my public evernote.

Spring SystemPropertyInitializingBean

When using POI in any of your projects, and the application you’re building is a web application, you probably have it running on a Windows machine. If not, you know all about the struggle with the “headless mode” environment setting to tell the JVM how to handle graphics rendering.

I always like to keep my applications as clean as possible to the users. The system administrator is also a user of the software (during installation at least). So I wanted the application to set the environment properties itself, In this case, I built a nice little Spring bean to handle this. The solution is so simple, that it is almost a brilliant display of what Spring can solve for you. Suddenly, all these environment setting problems turned into a simple Spring configuration problem. Here’s how:

Ibatis 2.2 Ignores XML encoding

At my company, we’re using Ibatis to do operations on Oracle databases. As most of our software is designed to be international, we keep our XML files in UTF-8 encoding. Recently we discovered that Ibatis had some trouble parsing the XML files when we were using diacritics in them. As it turns out, Ibatis 2.2 actually ignores the “UTF-8″ setting in the XML file header altogether.

This was actually reported as an issue at apache’s issue tracker, and fixed in Ibatis release 2.3 and upward. In the meantime, if you can not swich to a new release because of tight deadlines and no time for regression tests, you can set the file.encoding property to UTF-8, because then Ibatis will parse the XML in the correct encoding.