Kaffeinate yourselves

Bud, Arunan and I have decided to launch a GNU/Linux magazine for the Sri Lankan GNU/Linux newbie. My article on Kaffeine is available from yesterday.

The next article due by me is on amaroK. However, I need to do a dist-upgrade from my Ubuntu Breezy to Dapper to get the latest version of amaroK.

So.. Go Kaffeinate yourselves in the meantime... :)

FOSS-ed for Hackers

A very productive two days at the FOSS-ed ended yesterday.

The first day was graced by Professor Lawrence Lessig , a co-founder of Creative Commons who did an excellent presentation on the concept of 'commons' and the importance of 'freedom' for innovation.

This time I got the opportunity to conduct a session as well on Gambas. It was a good audience who were keen to learn. I guess FOSS in Sri Lanka is becoming mainstream. It's apparent by the large number of corporate participants along with the university students.

Google Web Toolkit :: First Impressions

Get it here

Just got the toolkit up and runing along with a project in Eclipse. I have been trying all sorts of javascript libraries trying to develop a satisfactory AJAX PoC for a while now. I was not very happy with the results.

With the Google Web Toolkit, I (mostly a java guy) was able to get a basic 'Hello World' AJAX application running in record time. Eclipse integration is simply great, which brings in the ability to debug AJAX applications in a 'civilized' manner, among other things.

The documentation and the samples were very helpful in ramping up. I'm now looking at the RPC and the surrounding architecture. I think this would be the toolkit that made AJAX 'usable' for a broader subset of developers.

Hope to see great things in the coming days ....

Installing CDAX on Linux

The text below applies for the CDAX version 5.4 (and will apply for past and future versions if the issues are not solved).

First and foremost, for the moron who developed the installer and hosted it at the site ... Thanks for nothing !!!. Go and;

a. Read the installer creator's manual before writing installers with it.
b. Learn Linux before pretending you know how to write installers for it.


For the rest of you guys here's how to clean up this mess and set up the CDAX software on your preferred Linux distro.

After downloading the .bin file and giving it execute permissions, don't even think about running it again and again. It's a bloody waste of time. Just go to step 1 below.

Before going to step 1, let's dissect what this guy has done. After running the installer and it dying out, there will be 2 log files generated in the same directory. These are named 'errors.log' and 'jinstall.log'. The most important information can be found on the latter. Going through it we can see what the 'wannabe' installer maestro has done.

First, he has turned 'off' the JVM search functionality, which means irrelevant of the fact that I already have an up-to-date JVM installed, the installer will install it's own JVM. (In case you were unfortunate enough to download that 30 MB installation using a dial-up connection, keep in mind that the bulk of that file was the JVM and not the actual CDAX software. He should have put two installers with/without the JVM included.)

Then after extracting his JVM to my hard drive, the installer tries to execute the 'java' executable inside it, without bothering to set execute permissions first. Obviously the installer goes south from that point on.

So that about sums it up for the dissection. I hope I wasn't too harsh on the guy. On second thoughts... No I don't hope so. If you are putting out a software (along with the image of your company at stake) on the line, you should spend time to find out whether the installer works on all platforms. I wonder what the story is with the Macintosh users.


Now let's see how I got this thing working in my Ubuntu Breezy.

Step 1: Run the installer with sudo (or as root, whatever fancies you ...)
Step 2: After the installation fails :) Go to the directory where the installer puts its JVM in. That would be /usr/local/bin/jvm/jre1.5
Step 3: Give the 'java' executable execute permissions, so that it can be executed by a normal user.
Step 4: Run the installer again as a normal user. Voila !!! The wizard starts and it's point and click time from there on..
Step 5: Now to get rid of this VM (if you already had one installed and this was force installed). Deleting this VM and creating a simlink to your original 'java' executable should cure that irritation.


Hope this helps ....

Interviewing Developers

I came across a really interesting post from Joel, while doing some background work for an industrial day. I'm in a panel to hire new interns who might be potential employees.

I loved the part that says,

"Smart is hard to define, but as we look at some possible interview questions we'll see how you can ferret it out. Gets Things Done is crucial. People who are Smart but don't Get Things Done often have PhDs and work in big companies where nobody listens to them because they are completely impractical. They would rather mull over something academic about a problem rather than ship on time. These kind of people can be identified because they love to point out the theoretical similarity between two widely divergent concepts. For example, they will say "Spreadsheets are really just a special case of programming language" and then go off for a week and write a thrilling, brilliant white paper about the theoretical computational linguistic attributes of a spreadsheet as a programming language. Smart, but not useful."

Is Wikipedia a threat or a menace?

Is Wikipedia a threat or a menace? by ZDNet's Dana Blankenhorn -- Just like the GPL, Wikipedia carries with it responsibilities along with rights.

WiFi (non)Security ....

How can I protect my wireless network ? Well I found what NOT to use


1. Mac Filtering

Spoof the mac address in linux by ;

/etc/init.d/networking stop
ifconfig eth0 hw ether 00:01:02:03:04:08 <== desired mac :)
/etc/init.d/networking start

More info on other systems found here


2. WEP (Wireless Equivalent Privacy)

This method, as it seems was pretty weak from the begining. There's a step-by-step approach to cracking it here

Hmmm ... try kismet and airsnort ... I rest my case ;)


With these two gone, The Other alternatives AFAIK would be to;

1. Hide the SSID
2. Disable DHCP and assign static non-routable IPs
3. Use WPA instead of WEP

I found a good intro here, while googling, which gives a step by step guide to configure your router for security.

Java JRE/JDK Installation on Debian with java-package

An excellent article I found while doing research to create Debian packages for Sun's JDKs for our Taprobane distro.

Tracking down causes of exceptions in Eclipse

NOTE: I found this in a Blog somewhere.. Thanks and due credits to the author, who ever he/she is :)

BEGIN QUOTE

If you like me is getting tired of seeing "Unhandled event loop exception, Reason: someexception" and no stacktrace in Eclipse then try the following:

Create a file e.g. .eclipseoptions with the following contents:


# Turn on debugging for the org.eclipse.ui plugin.
org.eclipse.ui.ide/debug=true
# Show a dialog with details button when an internal error occur.
org.eclipse.ui.ide/debug/internalerror/openDialog=true
# Print exception stacktrace to console
org.eclipse.ui.workbench/debug=true


and then run eclipse with -debug .eclipseoptions and you will get the full stacktrace
as normal in the log but also on the console (clickable) and in a dialog when the exception occurs - no need to go looking in the log what just happend.

p.s. try to include the following too:


# Enable heap status monitoring
org.eclipse.ui/debug=true
org.eclipse.ui/perf/showHeapStatus=true


Gives you a nice hint about memory you are "utilizing"

END QUOTE

FOSSSL Codefest

Well the codefest is in progress as part of our FOSS Week. Although I was involved in organizing, didn't take part in the actual event, since I couldn't see how I cn contribute ... being a Java guy :(