Wednesday, September 8, 2010

What has Maven ever done for us?

I've recently been learning about Maven and building a list of reasons why to use it on a new project rather than Ant. I found this blog entry and it fits perfectly: What has Maven ever done for us?

I also love that it is a spin off from Life of Brian

Thursday, September 2, 2010

JUnit testing with Derby and DbUnit

I've been having quite a bit of trouble setting up a JUnit test case that uses Derby and DbUnit. I've searched and searched on Google for answers and put bits and pieces together but nothing seemed to be solving my exact situation.

First of all I'm dealing with a fairly old application that was written in Java long ago and has very little JUnit in it. We've been trying to improve this by adding JUnit when possible. So I was assigned the task of changing some SQL and I figured this would be a good opportunity to add the use of an in-memory database.

We use DB2, so a natural fit is to use Derby since the SQL should be fairly similar. I have used HSQLDB a few times in the past and don't remember running into too many issues getting it to work. With Derby, however, I ran into a couple of snags. I thought I'd capture some of them here in the hopes that someone will chime in with better ways to do it or in the slim chance this might actually help someone else.

My first challenge was trying to get around the code being tied to a datasource and not running in a container with JNDI made that something I wanted to avoid. After making a few changes to the service implemenation to make it have the datasource injected I finally got around the need for a mock implementation of JNDI.

Then next challenge was getting Derby to work. I started by grabbing the Derby jar that is included with RAD 7.0 in the shared folders. I came to find out that this version of Derby does not support doing a memory only DB. Upon running the basic JUnit test case I created so far I saw it generate a log file and a whole directory full of files for the database. I figured this isn't good for JUnit because you'd have to delete the directory after each test run. In frustraion, I researched a bit and found that starting with Derby 10.5 there is support for an in-memory backend. I downloaded the newer version and ran again. What!?! It is still generating the file system. I did some more research and determined I needed to change the connection uri to "jdbc:derb:memory:derbyDB;create=true". Reran the test and this time the directory was not created.

It feels like I'm making some progress, so I thought I'd add another simple test case. This caused some new issues because Derby didn't appear to be cleaning up between test cases. Probably uses a singleton for the in memory database, so not restarting the JVM caused the table to already be there. To get around this I created a method that would create a random connection URI so that each test run used its own schema.

Looking back at the work I did, the setUp method was creating the table. This probably could have been changed so the table was created in the constructor and then have the setUp or tearDown just empty the table out. Then I wouldn't need to have the random connection URI.

Anyway, here is a link to the project which can be built with Maven.

Monday, April 26, 2010

The Netbook

I've recently been using an iPod Touch a lot to check email and surf the web. It was handy because it was small and was fairly easy to use. The biggest drawback was the lack of a keyboard and the tiny screen. So along comes the iPad and I thought great maybe this is what I want. Then I was listening to the Java Posse and heard Dick talking about his netbook and how he used it and loved it. So I was thinking, I'm not a big fan of Apple because of their "we have to approve everything" model. Plus the fact that I had to pay to upgrade the bios on the iPod Touch. So I figured I'd get nickel and dimed like crazy with an iPad.

Anyway, I decided to go with the Samsung N210. The major determining factors for me were wireless N and a web cam that was over 1 megapixal. Other things that helped were the cool white color, no glare screen and easy to use keyboard.

My first impressions of it are pretty good. It came pre-installed with Windows 7 Starter, which I think is a piece of crap. The Starter version disables the ability to playback movies in Windows Media Player. Why even do this because I easily downloaded another open source movie player tool and can play movies from my thumb drive now. The other really dumb and annoying disablement is the desktop background. Can you believe they disabled the ability to change the background? What's that about? All I can think is they probably sell this crappy version for next to nothing with the expectation that most people will upgrade.

Since this is a new blog I should point out that I am very Linux biased and it is my OS of choice. So, my intention from the beginning of purchasing a netbook was to install Ubuntu remix on it. So shortly after playing with Windows 7 and realizing it isn't much better than Vista, I installed Ubuntu 10.04 (beta 2).

All I have to say is WOW! Ubuntu remix version is pretty slick. The creators of this really did some good work. The interface is customized for the smaller screen and it is super easy to use. My wife even likes it.

So just to wrap it up fairly quickly, I like it. I still have some work to do to figure out how to get movies to play because I'm getting a weird error. But from what I've read so far it seems to be a new thing for Ubuntu 10.04. Since I installed a beta version, I can't complain about that too much. Everything else seems to be working well. Wireless is connecting with no extra setup. The one last thing I want to praise about Ubuntu is the memory usage. Windows 7 was using about 75% of the 1GB of RAM. Ubuntu only uses about 30%.