Usually, I do most of my Maven and debugging stuff in a terminal console. But others will prefer to use Eclipse! And I can understand why, since its DDMS perspective is so powerful and easy to use.  Here’s how you can do it:

1. mvn clean package
2. Deploy the target/xxx.apk to the device
3. Open DDMS perspective in Eclipse
4. Select the process you want to debug/trace
5. There you go!

Debugging running APK in Eclipse DDMS

Xubuntu is Ubuntu-based and features XFCE, a old friend of mine “who” I used to have fun with back in the days when my hardware sucked – which now is totally not the case, since I’m relying on a I7 3.4GHz + 16GB DDR3 + OCZ Vertex 3 SSD disk.

And so it was, I downloaded the 64-bit alternate ISO, burned it and after 20 minutes my system was up and running. Boy, did I miss this.. you came a long way XFCE, and you still rock!
Besides lacking some of the integration I was used to in my now-gone-Gnome-days, the simplicity of this window-manager is making me really happy. In case you’re feeling the same way about Gnome 3 and/or Unity, do yourself a favor and give it a try!

Here’s some hints you may find useful. I’ll be updating this list!

• Two DVI monitors side by side with xrandr

# Dual Monitors configuration on Xubuntu

# Monitor Order
xrandr –output DVI-I-1 –left-of DVI-I-2

#Tip: to configure it, exec ‘xrandr’ on bash to view the options by monitor

# Resolutions
xrandr –output DVI-I-1 –mode 1680×1050 –rate 60.0
xrandr –output DVI-I-2 –mode 1680×1050 –rate 60.0

# Primary Monitor
xrandr –output DVI-I-1 –primary

• Don’t quit Pidgin when you press the close button

Don’t disable libnotify integration plug-in (if it’s not enabled by default, then enable it). You can however turn-off all options of this plug-in.

• Dropbox support for Thunar file-manager

execute sudo apt-get install libthunarx-2-dev
and then follow the instructions available here.

First of all, the Gerrit instance I’m working on is authenticating against the company LDAP directory. Nothing new here as LDAP users can log-in sucessfully. Now, the thing is Gerrit process is not running as an LDAP user, but rather an Unix one (local) and we need a Gerrit user (non-local) with a public SSH key for Jenkins to be able to acess the code review tool.

The confusion was set! How would I authenticate Jenkins without an LDAP user created for this sole purpose?! gerrit create-account is the way to go!

For this command to work, you must have an authenticated user in Gerrit with administrative privileges and public SSH key set.

First, let’s create a key for the user that Jenkins is going to use:

ssh-keygen -t rsa -b 2048

You should now have two new files, a private key and a public key. Never ever give the private key!! Imagining your recently created public key file is named id_rsa.pub and that you’ve got an xpto user configured in Gerrit as part of the group Administrators, let’s add thevirtual user:

cat id_rsa.pub | ssh -p 29418 xpto@gerrit.example.com gerrit create-account --ssh-key - jenkins

It should be OK now! Just install Gerrit Trigger Jenkins plug-in and configure it as described in the documentation. It won’t take more than two minutes before you’ve got Gerrit shaking hands with Jenkins

The pre-requisites are:

• MySQL up and running and experience creating databases and defining privileges;
• Glassfish up and running and the experience creating JDBC Datasources and deploying applications, including managing library dependencies for JDBC and others – in this case, you’ll need to provide MySQL JDBC driver and Bouncy Castle crypto API libraries to Gerrit.

If you’re ready, follow me now:

1. Create a database for Gerrit

           mysql -u root -p
   
           CREATE USER 'gerrit2'@'localhost' IDENTIFIED BY 'secret';
           CREATE DATABASE reviewdb;
           ALTER DATABASE reviewdb charset=latin1;
           GRANT ALL ON reviewdb.* TO 'gerrit2'@'localhost';
           FLUSH PRIVILEGES;

2. Download the latest version of Gerrit. By the time of this writing, it was 2.2.1.
3. Initialize Gerrit in standalone mode (for now). Don’t forget to provide the correct MySQL configuration:

   java -jar gerrit-2.2.1.war init -d gerrit

If all goes well, you should have a new directory named gerrit with everything you need to get Gerrit running. Also, the standalone server (Jetty) should be up. Stop it:

    gerrit/bin/gerrit.sh stop

Now, let’s configure Glassfish datasource. Please, pay attention as this was where I got into problems..

1. Create a JDBC Connection Pool with type javax.sql.DataSource and MySQL as datasource classname.
2. Enable Ping mode.
3. Define DatabaseName, User, Password, Server depending on what information you’ve provided while initializing Gerrit.
4. Finally and most importantly, define both URL and Url properties to something like jdbc:mysql://localhost:3306/reviewdb?autoReconnect=true
5. The parts in italic bold are the ones to change according to your own configuration.

Try to ping your datasource to check if it’s OK. It is? Great! Now, let’s proceed with the deployment of Gerrit:

    asadmin deploy --contextroot codereview --name gerrit-2.2.1 gerrit-2.2.1.war

It should be working now! Point your browser to http://your_host/codereview, et voilá

Gerrit working on Glassfish application server and on top of MySQL

To achieve this, just add the following lines to your pom.xml:

<repository>
    <id>repository.jboss.org</id>
    <url>https://repository.jboss.org/nexus/content/groups/public/</url>
</repository>

Then, just use your favorite POM editor and add the org.hibernate dependencies as you see fit.

Front

Back

On my previous setup, I used to have Ableton Live 8 configured to use only the first two unbalanced outputs as I didn’t need the other two for what I was doing. But now, I want to have the ability to cue some clips before sending them to the wild, as I’ll be working with multiple external audio sources (i.e., turntable).

First things first! You need to install the official driver and activate the third and fourth unbalanced outputs. On MacOs X you’ll have a specific preference pane for that available at System Preferences. Then, you’ll have to configure the soundcard in Ableton Live! Don’t forget to activate the third and fourth outputs.

Ableton Live 8 soundcard configuration

I’m not going to explain how to enable cueing in Ableton Live. Instead, I’ll describe what was bothering me with my current setup: the third and fourth outputs were only sending noise.. very noisy noise!! After several try-outs (changing cables, reinstalling the driver, reconfiguring Ableton Live, testing in a different Macbook, etc.) I started to believe that my soundcard was faulty. Happily, I was wrong..

After much reading on the web about issues with this particular model, I found out that some guys had trouble with IRQ sharing. And then it stroke me! I’m using one of those cheap USB hubs for all my USB gear (five pieces at the moment) as my Macbook provides only two USB ports. The soundcard was connected to it. So, I simply connected the soundcard directly into the Macbook and “it just works! ™”

Even that the solution is not much of rocket science, perhaps this post will help some noob like me in a similar situation.

Cheers

Hello fellow geeks.

Yeah, it’s true, I have one thanks to my buddy Nuno Tavares from NET7, who so gently “offered” it to me (kudos to him!). It’s only been two days since I got my hands on it, but I’m totally in love for this black beauty.

HTC Hero Black

You probably remember my post about the E71 vs IPhone and how happy I am (was) with that Nokia device, but after touching one of this, and having so many applications at hand, and that astonishingly cute user interface, I’m completely surrended! This Android-powered phone is a killer!

It comes with no carrier-blocking stuff, but still, as any respectful geek out there, the first thing I did was to investigate how could I make the experience better. I read that the HTC Sense UI was somewhat slow, and that an upgrade, which is expected in October, would solve that. But, curiously there is already a “preview” (of that update) in the wild!! The instructions are easy and are as following:

1. Root your phone
2. Download one of the two ROM images available in the previous link to the phone’s SD card
3. The ROM comes zipped. Change its name to update.zip
4. Boot your phone into the recovery image (press Home key and turn your phone on)
5. Do a “nandroid backup”
6. Wipe your phone/reset it to factory settings (it’s a new device, I didn’t lose a thing!)
7. Select “apply sdcard:update.zip”
8. Wait and then restart when this option is available (after upgrading)

The first boot will take some time, but it’s worth it.

Now, the phone I got is prepared to Poland/Romania/Czech Republic, and I don’t know why the update didn’t remove this and enabled me to select Portuguese (word suggestion, dictionary, etc.). The English language, though, is available and it was OK for me. Still, one good thing about this update is that there is this Custom Locale application who allowed me to set the locale to PT_pt, which changed the language to portuguese. There is no word suggestion or dictionary, though (and until there are, these functionalities are disabled!).

Also, for the portuguese reading this, I’d like to publicize one, and perhaps the only portuguese Android community, AndroidPT.

Enjoy! ..I surelly am

For sometime now, I’ve been looking forward to acquire an embedded system that would become my home router and testbed for some networking stuff I’m working on. The requisites are the following:

• Noiseless, cause I want to sleep with it right next to me
• Very small
• x86 architecture, cause I want it as a testbed for my networking applications and don’t want to fiddle with architecture vs compiler/libraries issues
• Two or more Ethernet devices
• USB and mini-PCI are pluses
• Cheap!!

Thanks to my friend João Barraca, I went for a PC Engines Alix ALIX2D3. And must I say, it’s great!! And only 104Euro + 26Euro (customs taxes).  I’m not showing the unboxing process, but here’s a picture of the board.

ALIX2D3 board

I did some things wrong though, on the rush of getting a new toy (don’t you geeks know this feeling?!). First PC Engines is based in Switzerland, and therefor non-EU, and therefor customs taxes and a long wait for the delivery. Then I ordered the board and a black case only, so at arrival, I missed a DC, a Compact Flash card and a null-modem serial cable. I went to one of those big electronics market and bought the following:

• Vivanco universal DC 7v-24v (I recommend setting it for 18v, depending on the number of devices you’ll be using, such as USB and mini-PCI stuff). Oh and be careful with the polarity of the board which you can find by looking down the FB18, and using the correct connector size, 2.1mm.
• Sandisk CF Ultra II 4GB;
• Null-modem serial cable (female-to-female);
• Serial-to-USB adapter.

As I said, I also ordered a black case and I had an issue while assembling the board into it. The serial port hex nuts wouldn’t fit the case! Well, just remove them, insert the board, and attach them again. In the end, this is the result:

Board in the case

Front of "the machine"

Size compared to the E71

I recommend you install everything you need and test it before you put the board into the case, so you can avoid repeating the screw/unscrew process.

Now, let’s head for the installation.

1. First, grab the alternate installer for the latest Ubuntu i386 (9.04 iso). Burn it.
2. Plug your CF card into a USB card-reader and punch it in your PC/laptop.
3. Boot from the CD and press F4. Select text-only system installation.
4. Install Ubuntu into your CF. I recommend setting only one partition and not using swap as you don’t want to “burn” lifetime from your CF.
5. Don’t install grub into the MBR of the first disk, but on the MBR of the CF.
6. Reboot.
7. Boot into your CF Ubuntu system and log-in.
8. Install an ssh server. sudo apt-get install openssh-server
9. Edit your /etc/network/interfaces and configure your network devices as you see fit.
10. As you’re using your PC/laptop for the installation process, udev has persisted the currently existing network devices. You must remove all entries before putting the CF into the ALIX2D3 board, so that all Ethernet devices there are correctly named (eth0, eth1, eth2). Just issue echo “” > /etc/udev/rules.d/70-persistent-net.rules
11. In order to protect the CF once more, edit your /etc/fstab and change relatime to noatime in the root line (/). Also, add the following lines:

none /tmp tmpfs nr_inodes=200k,mode=01777 0 0
none /var/tmp tmpfs nr_inodes=200k,mode=01777 0 0

Power off. Now, put the CF into the board and have fun through ssh. Enjoy

Been 2 months since my last post, I know. I have been quite busy at work! And I guess it’s time I talk a little bit of what I’m doing since November.

Well, for a start I left Nokia Siemens Networks for PDM&FC (I know the website is old, and not trying to excuse the inexcusable, let’s say that people there are actually busy working on real stuff). Anyway, leaving a corporate for an SME was a refreshing decision! I didn’t feel productive anymore, and that was something I couldn’t stand. People were great, though

Arriving at the new company was nothing as I had in mind. In the initial couple days, it was hard to find someone who could spare some time pointing me what to do and where to start. Soon, I realized everyone was so very busy working on their projects. Nonetheless, I was kindly received by my new coworkers, and I was eager to start showing what I’m able to do.

I started with some minor tasks like writing some Python + Gstreamer code for video-transcoding stuff; then some PHP spaghetti; ending with architectural design discussions for a scalable web service-oriented platform. But the true thing I was recruited for was yet to come, the EU-funded project (FP7) HURRICANE.

HURRICANE aims at delivering a framework to enable and execute seamless handover between heterogeneous radio access networks like 802.11, 802.16 aka WiMAX, DVB-H and 3GPP (UMTS). Let me throw some major concepts so you can better understand what I’m doing..

• Handover – process of transferring an ongoing call or data session from one channel connected to the core network to another (see Handoff);
• IEEE 802.21 – aka Media-Independent Handover (MIH) Service, this emerging standard is the base for this project, comprehending the facilitation of handover analysis procedures. The resulting decision process and execution is out-of-scope of the standard.

And this is what HURRICANE proposes: to provide an implementation of the .21 standard, some handover-decision/execution modules on top of it, and also the lower-layer access to the identified RATs (Radio Access Technologies).

My main function on this project is to implement the proposed framework. Starting on the .21 generic service, the MIH Function (MIHF) and going through several stages of the link-layer (I hope to skip the real part on this), we’ll end by having, I hope, a real seamless handover between 802.11 and 802.16 – there are some more scenarios defined, but due to hardware access limitations, I don’t believe they’ll be fully deployed – powered by HURRICANE. Also, I’m the responsible to study (done!) and implement a PMIPv6 module to IP-mobility on top of this architecture.

A lot of work has been done, but there’s much more to do! I’m thrilled to see what we’ll achieve by the end of this year. In the meanwhile, I’ll be posting about casual stuff I shall be working on

Cheers to you all, and cya soon!

Yours truly

Super-cool MIPv6 testbed

Enjoy you geeks!