Usually, when I come home from work, I am pretty tired of programming and rarely ever do any programmin during weekends. But this weekend was different. I have been coding pretty much at work lately, so it should not be because of abstinence from coding. Anyhow, I set down and contributed to a small open source project started by a former colleague of mine. It is called Architect’s Java DAO Generator, and you can find it on Sourceforge. In short it is a maven plugin that generates most of the boilerplate code you usually have to code by hand. It also abstracts the data access layer from your domain logic in a nice way. Version 1.5 is soon going to be available and is absolutely worth a look.
Java
Candidate for Daily WTF
To cry…or laugh…that’s the question…
@Test
public void spaceFiller() {
int l = 5;
String result = MessageUtil.spaceFiller(5);
if (result.length() == l) {
} else {
fail();
}
}
When I came across the test code above I wondered who on Earth would write such a thing. The answer came shortly after when I had a look at the method it is testing…
/**
* Space filler.
* Creates a string filled with spaces of the wanted length
*
* @param length the length of the wanted string
* @return the string
*/
public static String spaceFiller(int length){
String s = "";
for(int i=0; i < length; i++)
s = s.concat(" ");
return s;
}
The good thing is that they actually wrote a nice and clear JavaDoc explaining their own stupidity…
Are Unit Tests Necessary?
At work today I came across a project that had not written a single unit test for their new code and wondered what the hell they were doing. Nothing unusual except that apart from the usual excuses about time constraint etc., they had the guts to challenge the value of unit tests. I did not believe what I heard and for a moment wondered if I had gone through some kind of time capsule when I was visiting the pyramids in Cairo last week and come back in a time before unit testing was invented. But a quick glance at the date on my watch ensured me that it was still 2010.
The only comforting thing about this is that as long as there are projects like this, there will be plenty of work for software consultants to clean up the mess. Just a pity that the first couple of weeks will be spent writing unit tests to be able to start refactoring the code. Good thing that writing unit tests are pretty fun and addicting, or to quote one of Kent Beck’s tweet earlier today “… tests are like potato chips”.
Corporate Blogging – a fresh (re)start
I have agreed to contribute with a post once in a while on the corporate blog, or newsroom as they call it. I know I have not been very active on this blog lately, but hopefully this will inspire me to be more active here as well. Having just come back from a couple of weeks of total relaxation and diving in Dahab, Egypt, I should be full of energy and an urge to get started writing.
But first I want it to be absolute crystal clear that the stuff I write her on AgileJava is my view, and my view only. It is by no means affiliated with the company blog or anything thereunder. The posts on the newsroom will be reviewed by company representatives before published whereas AgileJava is only reviewed by myself.
Scala Tutorial
While I was reading up a little on Scala recently, I found out that I might as well contribute a little while doing it. So I translated the Scala Tutorial to Norwegian since that was one of the translations missing. You can find it among the other translations on scala-lang.org or simply click on the image below to access it directly.
Android Emulator Workaround
Here is a small tip if you are having trouble running the Android Emulator for code that calls native methods and getting an error message similar to this:
JNI WARNING: method declared to return 'Ljava/nio/ByteBuffer;' returned 'Ljava/nio/ReadWriteDirectByteBuffer;'
... ;.nativeAsBuffer ('Ljava/nio/ByteBuffer;' not found)
The simple workaround is to add the following to the onCreate method of your main activity:
ByteBuffer dummy = ByteBuffer.allocate(0); dummy = null;
This way the classloader is “forced” to load ByteBuffer. This is not needed when running on a device, only the emulator as it seems.
Android Development for Google Nexus One
This post is just a repeat of my tweet yesterday, but I feel that it is easier to search it up again here than on Twitter. A good tip can never be repeated often enough anyway…
If you are setting up the development environment for Google Nexus One in Linux by following the instructions on Android Developers you will probably notice that the the device is not listed in vendor id table. One could believe that it could be the same ID as HTC since it essentially is a HTC device, but that is not so. Google has given it a vendor id of its own (’18d1′). Why it is not listed here is a mystery, but anyhow; this is how you solve it:
Add the following line to /etc/udev/rules.d/51-android.rules
(If the file does not exist, create it.)
SUBSYSTEM=="usb", SYSFS{idVendor}=="18d1", MODE="0666"
Restart udev:
sudo reload udev
Then unplug/plug the device, and you should be able to see the device by running
adb devices
NetBeans and Android Tip
Developing Android applications using NetBeans is usually as easy as stealing candy from a baby. But the last couple of days I have been struggling with an application that uses a couple of external libraries. The other developers (using Eclipse) have a couple of scripts that they run to get the .so files included in the .apk file. When I tried running the same scrips on the .apk generated from NetBeans, the application failed to start in the emulator. I nearly switched to Eclipse (god forbid), but then I saw the light again. As it turns out, NetBeans does not include the java api jar-files in the external libs in the dex-file by default which resulted in a ClassNotFoundException.
The solution is as simple as you would expect when you have used NetBeans for a while. Add the following to the build.xml file in the project root (replace the dummy values for the signjar target):
<target name="-pre-jar">
<copy todir="${build.classes.dir}">
<fileset dir="${external.libs.dir}">
<include name="*.jar"/>
</fileset>
</copy>
</target>
<target name="-post-jar">
<zip update="true" destfile="${dist.apk}">
<zipfileset dir="${external.libs.dir}" includes="*.so" prefix="lib/armeabi"/>
</zip>
<zip destfile="tmp.apk">
<zipfileset src="${dist.apk}">
<exclude name="META-INF/*.*" />
</zipfileset>
</zip>
<move file="tmp.apk" tofile="${dist.apk}" />
<signjar jar="${dist.apk}" alias="alias" storepass="secret" keypass="secret2" keystore="my_keystore"/>
</target>
You also need to add external.libs.dir=<your lib folder> to you <project root>/nbproject/project.properties file.
Now you can install the resulting .apk file using adb install or by running/debugging directly from NetBeans. Remember to follow the tip for asset-files in a previous post if you have that kind of resources.
Android Emulator and NetBeans
Whenever you ask or search for help regarding Android development, you end up with some fix related to the Eclipse ADT plugin or the Android SDK tools. My intention is to fix that by repeating parts of a great tip I found at Tim Perry’s blog. It is about how to get hold of the resources placed under the /assets folder in you Android project while running your applictaion in the Emulator from NetBeans. If your application tries to access resources from the AssetManager you will get a FileNotFoundException. The reason for this is that the assets are not packaged with the .apk like it is if you package and deploy it using the SDK tools.
The solution is:
- Go into nbproject/project.properties and add ‘assets.available=true‘
Voila! You will now be able to run, debug and step through your code as you would expect.
Google App Engine
It is amazing what a month in South Africa does to you. Things like Twitter, Facebook and blogging becomes pretty distant… But now I have been home for a while, Sun+Oracle has been approved by EU, I have finished (almost) my kitchen renovation and celebrated yet another birthday, so it is time to get started again!
After a discussion with a colleague at a coffee break this morning, I decided to try out Google App Engine. The getting started guide is a great place to start. It gives you a great walk-through setting up the development environment and creating a sample application. Since I am no big fan of Eclipse, I installed the Google App Engine Plugin for NetBeans. After resolving a small issue regarding path settings (see solution here), it was up and running perfectly.
Next steps will be to figure out what changes that has to be made to my existing applications to be able to deploy them on app engine. Probably the server side of YouOweMe will be the first candidate. Or maybe the KanbanFX server. I haven’t decided yet…