just girl talk...

search vs research

2009-06-06T11:17:00.005-03:00

People have this habit of googling for just about everything, it's nice when there's no serious work involved, as programmers can find themselves completely missing the point (as the elders used to say: rtfm!). Programming shouldn't be taken as lightly as copy-paste and searching for magic recipes on google, specially if you are missing the fundamentals of the code at hand.

If you find yourself in doubt on how to proceed or how to do something in this or that programming language and so on, I recommend taking the obvious steps first:

1. read the fine manual
2. read the API documentation
3. search in the official channels of the language/framework/whatever
4. read the fine manual again

Google "feeling lucky" should be your last resort, retwitting me: these kids are graduating in google university...

lempel-ziv-markov chain algorithm

2009-05-16T15:18:00.007-03:00

If you like minimalistic approaches and strive to keep your (*nix) installation to a bare minimal, this is good news.

LZMA is gaining adoption and the SDK (from 7z) is public domain for a while now. 7-zip has used this compression for a long time now, Zenwalk has already adopted, besides openSuse and I guess the new kernel images too.

This month was announced that slackware packages would be compressed by xz instead of gzip. From the changelog:

Fri May  8 18:49:03 CDT 2009
Hello folks!  This batch of updates includes the newly released KDE 4.2.3,
but more noticeably it marks the first departure from the use of gzip for
compressing Slackware packages.  Instead, we will be using xz, based on
the LZMA compression algorithm.  xz offers better compression than even
bzip2, but still offers good extraction performance (about 3 times better
than bzip2 and not much slower than gzip in our testing).
(...)
As an example of the compression improvement with .txz, have a look
at the kernel-source package:
Before:  kernel-source-2.6.29.2_smp-noarch-1.tgz (73808508 bytes)
After:   kernel-source-2.6.29.2_smp-noarch-1.txz (49150104 bytes)
The size of the main package tree in /slackware has been reduced from
1.9GB to 1.4GB by converting most packages to .txz.
Most of the packages have been converted from .tgz to .txz, but we
will continue to make the gzip, pkgtools, slackpkg, tar, and xz packages
in .tgz format for the foreseeable future.
Enjoy!  And thanks to Lasse Collin for the great work on xz.  :-)

mavenizing seam

2009-05-04T00:57:00.004-03:00

While we Java programmers wait for JEE6/JSF2 to save us from the nonsense of selectitems, poor el, lack of conversations and annotations of JavaServer Faces, frameworks like tomahawk, spring and seam try to fill this gap. I prefer Spring's approach, but as I currently use JBoss Seam at work, I'll write a little about how to get started in this technology.

This text assumes a basic notion of maven and java (apt-get eclipse maven sun-java6-sdk if you will). Currently in 2.1.2.CR1, the latest release contains documentation, examples, and a "Getting Started" guide for running on Tomcat (besides seam-gen) for the simplest setup.

The example/jpa mentioned (hotel booking app.) has a Maven pom.xml, and with Maven set, we can import the project in eclipse and start it with jetty, how cool would it be for a quick-start? However, the project follows a non-standard layout, so you'll have to convert it to maven manually (that means moving packages to main/java, view to main/webapp, and resources-tomcat to main/resources). If you know Maven this shouldn't be much of a problem.

But then you will have to set the dependencies, as only the dependecy management is inherited. Basically you will need seam-ui, richfaces-ui, jsf stuff and hibernate (here is a full listing with deps and jetty plugin configured - diff with the original for a better picture). The unit tests depend on jboss-embedded and test-ng, so I'll ignore it for now. And for Jetty, you will need to change the persistence.xml replacing jta-datasource with hibernate-properties or by configuring JNDI (context.xml is provided for tomcat only).

To summarize, you have to:
1. convert the example to the maven src/main layout
2. configure pom.xml with jboss repository, jetty plugin and the deps. from the root's dependencyManagement
3. configure JNDI/persistence.xml

Finally, you can "mvn eclipse:eclipse", "mvn package", and at last "mvn jetty:run", and the example will be ready at localhost:8080 for testing. It doesn't get any easier than this, or does it?

The good son returns home

2009-04-11T13:37:00.005-03:00

My eeepc 701 distro of choice (zeee) stalled, and the others I tried (eeebuntu, easy peasy) weren't lightweight enough for me, even upgrading to jaunty-beta and all that (fast boot times is mandatory as the battery lasts for just 2-3 hours), so after reading in some blog how the slackware-current was eeepc-ready, I decided to install zenwalk-standard from scratch (it is slackware-current after all). After a little help from unetbootin and a few tweaks, the installation was a breeze, and to my surprise X, wifi, and even the webcam worked out-of-the-box, besides, it was bundled with xfce 4.6.0.

Well, I acquired a laptop for work last week, a nice (refurbished, though) Toshiba U305 13.3'' 1.9kg. I needed mobility and it wasn't the case of my 15'' 2.9kg vaio, and eeepc can't run the java bloat I work with. So I decided, why wait 2 weeks for jaunty (I couldn't care less for upgrading all of the time...) when I could have a nice bleeding-edge linux with the USB img I created for the eee. And again, toshiba's hardware worked effortlessly: video, webcam (chicony), sound, front mic, wireless (4965AGN), SD reader (R5C822), with the standard linux 2.6.28.7 from zen.

That's it, I'm now officially a Zenwalk user, switching from Ubuntu/KDE back to my Slackware/XFCE roots. Zen's package repository has everything, besides slacky.eu, slackbuilds.org and packages.slackware for all the rest. Simplicity is divine :)

(background from kde-look.org)

new year, new blog

2009-01-01T19:45:00.009-02:00

Moving to blogger.com as wordpress charges for everything (domain forwarding, that is). Besides, I'll try to post in english (or engrish to be more precise) from now on, so now english is the primary language FWIW.

Thanks to the developers of wordpress2blogger.py and addToPicasa for making it possible.

PS: old blog link