My First Maven Plugin

Having been working with Maven and Tycho for about the last 8 months, it was high time I got around to writing my first Maven plugin, because I need to break myself from my tendency to revert to ant and bash whenever I need to do something outside the normal Maven flow.

So, first I imported the git sources for Tycho 0.11.0-SNAPSHOT from https://github.com/sonatype/sonatype-tycho so I'd have something from which to learn. Sure, Hello World samples are nice, but a working example is always more fruitful.

git clone http://github.com/sonatype/sonatype-tycho.git

Next, I imported a few Tycho projects (tycho-p2-facade, tycho-p2-plugin, tycho-p2-publisher-plugin) from the git clone folder into Eclipse using m2eclipse 0.10.2. Because these are Maven projects and don't need Eclipse project clutter, there are no .project files and therefore they couldn't be imported as pre-existing projects.

So, I had to wobble through the New > Maven Project wizard a little until I figured out that I could check the 'Create a simple project (skip archetype selection)' box to create a new .project file in an existing project folder. Only wrinkle here is that if there's an existing pom.xml in a project, the New Maven Project wizard complains. The obvious workaround is to rename the existing pom.xml to pom.xml_, create the new Maven Project in w/ m2eclipse in the existing folder (as above), then replace the pom.xml that m2eclipse creates with the actual (renamed) one, pom.xml_ and refresh the project in Eclipse. Voila! I also updated the project settings to use JDK5 instead of the default JDK1.4. You need only do File > Import > Maven > Existing Maven Projects and browse for the pom files. So much easier than what I did above. Thanks to everyone for setting me straight!

So, with sample code to clone from it was time to create my own plugin project, then a second project on which that plugin depended in order to test the dependency chain thru Maven.

The first uses the "maven-archetype-plugin" archetype v1.1; the second, the "maven-archetype-quickstart" archetype v1.1. Here are the two projects:

1. sample-plugin
2. sample-project

The glue between these projects is in the sample-project's pom.xml:

<dependency>
 <groupId>org.jboss.maven.plugin</groupId>
 <artifactId>sample-plugin</artifactId>
 <version>0.0.1-SNAPSHOT</version>
</dependency>

And that's seemingly it. Next... adding actual useful functionality to a plugin, then using that functionality in our JBoss Tools build's parent pom.xml.

In Which I Explain Once Again That Linux Is A Viable Alternative to Windows

I was recently asked this question:

Can linux be used for a normal computer, operating email programs, word processing, etc? I am quite frustrated with all the "improvements" that Windows keeps getting; each improvement making it slower and more prone to erratic behavior. I use a computer only for the above tasks, and would really like to get away from the problems.

As I've been telling friends, colleagues, family, and everyone who'll listen for about the past 5 years... YES.

• Mail: Instead of Outlook, you can use Thunderbird.

• Calendar: use Sunbird or go online w/ Google Calendar

• Web: Instead of Internet Explorer, Firefox, Opera, Chrome, or Konqueror. None will "accidentally" install spyware for you.

• Office: Instead of the bloated and dinosauric (20 years old!) MS Office's Word, Excel & Powerpoint, use Open Office's Writer, Calc & Impress. (Open Office is now 10 years old - old enough to be feature rich, young enough to be standards-compliant.)

• Chat: instead of MSN, use pidgin (supports all IM protocols, including MSN, Yahoo, gtalk, IRC, Twitter, Facebook) and/or Skype (for audio/video chat)

• Audio/Video playback & streaming: instead of Windows Media Player, VLC player.

• Solitaire: PySol includes 200 solitaire games; Firefox "Cards" plugin contains dozens more.

More advanced users:

• Graphics: instead of Photoshop, use GIMP

• MP3 ripping: grip or asunder

I personally use linux flavours designed for older machines so they're lightweight, faster, and less bloated. Then, if I need a more "bloated" app (like something from the KDE school instead of the XFCE or GDE school), I simply install that into the operating system as an add-on. Of course if you *want* eye candy (like 3D desktops and transitions when you open/close applications) you can get that too. It's pure eye candy, but it's available if you need Vista or Win7-like "bling".

If you want to try Linux before jumping in fully, I advise two options:

• Xubuntu, designed for old machines and to stay more-or-less the same over time. Download and install it into Windows without having to reformat your hard drive. Good for your grandmother's desktop machine.

• Fedora, designed for newer machines and to stay up to date with recent improvements in the Linux world. Can be installed onto a USB key so you can boot your system from that without having to touch your existing Windows install. Good for your parents or your machine, or for an office.

• There are of course lots of other Linux distros out there...

HOWTO: Find the feature that contains a plugin

Tycho is awesome.

However, like all build systems, it has its limitations.

One such limitation is that when you're building against a target platform, and something's missing, you get errors such as these:

[INFO] Cannot complete the request.  Generating details.
{org.osgi.framework.executionenvironment=OSGi/Minimum-1.0,OSGi/Minimum-1.1, osgi.ws=cocoa, osgi.arch=x86, osgi.os=macosx, org.eclipse.update.install.features=true, org.osgi.framework.system.packages=}
[Software being installed: org.jboss.tools.tptp.feature.feature.group 1.2.0.qualifier, Missing requirement: org.eclipse.tptp.platform.instrumentation.ui 4.4.1.v201009092123 requires 'bundle org.eclipse.hyades.probekit [4.2.0,5.0.0)' but it could not be found, Cannot satisfy dependency: org.eclipse.tptp.platform.instrumentation.ui.feature.group 4.3.1.v201009092123-797908s73533D4H6D56 depends on: org.eclipse.tptp.platform.instrumentation.ui [4.4.1.v201009092123], Cannot satisfy dependency: org.jboss.tools.tptp.feature.feature.group 1.2.0.qualifier depends on: org.eclipse.tptp.platform.instrumentation.ui.feature.group 4.3.0]
[ERROR] Internal error: java.lang.RuntimeException: org.eclipse.equinox.p2.core.ProvisionException: No solution found because the problem is unsatisfiable. -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: java.lang.RuntimeException: org.eclipse.equinox.p2.core.ProvisionException: No solution found because the problem is unsatisfiable.

The important part of that error message is as follows:

org.jboss.tools.tptp.feature.feature.group 1.2.0.qualifier
   requirement: org.eclipse.tptp.platform.instrumentation.ui 4.4.1.v201009092123 
      requires 'bundle org.eclipse.hyades.probekit [4.2.0,5.0.0)' 
         but it could not be found

org.eclipse.tptp.platform.instrumentation.ui.feature.group 4.3.1.v201009092123-797908s73533D4H6D56 
   depends on: org.eclipse.tptp.platform.instrumentation.ui [4.4.1.v201009092123]
     dependency: org.jboss.tools.tptp.feature.feature.group 1.2.0.qualifier 
        depends on: org.eclipse.tptp.platform.instrumentation.ui.feature.group 4.3.0]

So, how do you find which feature contains that plugin, so that you can add it to your target platform?

First, you need access to the repository. If you have direct server access to the repository from which the plugin comes (eg., the TPTP Helios update site), you can run this script in the root of that repository.

If you don't have server access (eg., you can't ssh to dev.eclipse.org and look in ~/downloads/tptp/updates/helios), then you can pull down a zip of the site (or use a p2.mirror script to fetch a copy of the site to your local machine)... and then run this script in the root of that repository.

Essentially the script finds matching feature jar files, unpacks them to extract the feature.xml files therein, and then greps those files for lines which suggest an included plugin matching the pattern for which you're searching:

$ findInFeature platform.probekit
./features/org.eclipse.tptp.platform.probekit_4.5.1.v201009092123-7H7BF8PAkF7B77ZARCNEK.jar
   <plugin
         id="org.eclipse.tptp.platform.probekit"

./features/org.eclipse.tptp.platform.trace_4.5.1.v201009092123-7L7O8bBgJ9E99jAfGWEM.jar
   <plugin
         id="org.eclipse.tptp.platform.probekit.launch"

From there, it's a trivial exercise to add another line item into your target platform file. First, paste in the feature jar:

./features/org.eclipse.tptp.platform.probekit_4.5.1.v201009092123-7H7BF8PAkF7B77ZARCNEK.jar

Then use vim to pattern-replace that string:

:%s/.\+\/\(org.\+\)_\(\d\+.\+\)\.jar/\t\t\t/g

And you'll end up with a new .feature.group added to the target:

<unit version="4.5.1.v201009092123-7H7BF8PAkF7B77ZARCNEK" id="org.eclipse.tptp.platform.probekit.feature.group"/>

JBoss Tools: making it easier to build against a complex target platform

So you want to be a JBoss Tools developer? Awesome. Welcome to the family. SVN sources are here, JIRA's over here and there's cold beer in the fridge*.

But you say it's a pain in the tuchus to download over 25 zips or add a whole bunch of update sites and hope you get everything you need? Yeah, no argument there. If only there was an easier way to resolve all the dependencies you need to get building, much less to even RUN this stuff.

To make this process simpler, I've created a p2 repo (update site) from our target platform file, which has been recently updated to include Helios SR1 dependencies. You can track subsequent work in progress here: JIRA JBIDE-6982. You can also report any issues there too.

---

So, now, just add this single site** into your vanilla Eclipse 3.6.1 Classic (or a Helios SR1 bundle), uncheck the box for 'Group Items by Category' and you can install everything listed. For great justice.

---

Some handy links:

• Latest Target Platform Repo
• Archived Target Platform Repo
• Target Platform Definition File
• JBoss Tools SVN Sources
• JBoss Tools JIRA

---

Some handy HOWTOs:

• HOWTO build JBoss Tools (all or individual components) using Tycho
• HOWTO run JBoss Tools' tests (all or individual components) using Tycho
• HOWTO attach Eclipse's debugger to JUnit or SWTBot tests running w/ Tycho
• HOWTO convert from a .target into a repo
• HOWTO update a .target to include newer versions based on contents of a local repo
• HOWTO install from p2 repo(s) into Eclipse using p2.director script

---

* - Due to beer2peer limitations, YMMV.

** - I'm aware that the update site throws a 403 if you open it in a browser. I can't be arsed to generate an index.html just yet, nor are there categorized features. Because really, you don't need either - this site is only meant to be used by p2.

Linux modem tethering with berry4all, Rogers 3G network, and Blackberry Bold 9000

Because I'll be out of town for the next couple days, part of my packing list included setting up tethering via my Blackberry.

First I tried barry but was unsuccessful in trying to make a successful connection.

Then I found berry4all.

I had two problems, but thanks to the extensive FAQ, I managed to solve them:

1. Ensure your device (in my case, Blackberry Bold 9000) has its APN correctly set in Setup > Options > Advanced > TCP
2. Ensure other network connections are disabled using route -n; ifconfig -a before attempting to connect via tethered 3G modem. See also If your PPPD does not support replacedefaultroute
3. Ensure /etc/resolv.conf is being correctly updated with the appropriate DNS entries (I have to do this by hand at the moment, but tweaked the default /opt/bbtether/berry4all.sh script to add this line so that I can automatically update the file immediately before connecting:

   #!/bin/sh
cp -f /etc/resolv.conf.bbtether /etc/resolv.conf
python bbgui.py &

   where /etc/resolv.conf.bbtether contains:

   domain rogers.com
search rogers.com
nameserver 64.71.255.198
#nameserver 64.71.255.253

4. Load up a bandwidth speed test such as bandwidthplace.com and see what network speed you can get.

Admittedly, tethered speeds are nothing close to wifi speeds.

• With Rogers 3G network and Blackberry Bold 9000 attached via USB, I managed to get about 500-2800kbps down and 100-200 kpbs up.
• With Rogers "Exterme" cable internet access (wifi @ home) I get 9800kbps down, 960kbps up.

But at least I can surf on my laptop using the 3G network while I'm away from the office.

To disconnect wired & wifi, then tether automatically and stay connected until CTRL-C is pressed, try this script:

#!/bin/bash
if [[ $UID != 0 ]]; then
 echo "Must be run as root!"
else
 /etc/init.d/network stop
 cp /etc/resolv.conf.bbtether /etc/resolv.conf
 route -n; ifconfig

 cd /opt/bbtether; python bbtether.py rogers -P **YOUR_DEVICE_PASSWORD_HERE**

 /etc/init.d/network start
 route -n; ifconfig
fi

p2 Repository Association And The Fine Art Of Forceably Enabling Disabled Sites 2: Tycho Edition

Back in February, I blogged about how to add associate sites to an update site generated w/ the Buckminster or B3 aggregator.

Since we've moved our build infrastructure to use Tycho + Maven, I had to port the script over to work there for our update site aggregation.

Here are the moving pieces:

• pom.xml that builds the site, listing input sites as <repository> entries, and a shout-out to build.xml, below, to do extra stuff during the install phase
• build.xml ant script called by pom.xml, above, to do additional work after the creation of the site_assembly.zip update site zip
• aggregateSite.jbosstools.properties properties file listing the aggregate sites to add

Troubleshooting Eclipse.org Mirrors / Using Profiles & Target Platform Definition Files With Tycho

If you look in the mirror and you say his name 5 times, he'll appear behind you breathing down your neck. - Candyman

If only troubleshooting mirrors was so simple. Have you ever been running a build or an install which stalls at the provisioning step, with a message like:

[INFO] Fetching org.eclipse.birt.integration.wtp.ui_2.6.0.v20100617-1315.jar.pack.gz (4.3MB of 46.13MB at 171.56kB/s) from http://mirrors.xmission.com/eclipse/birt/update-site/2.6/plugins/org.eclipse.birt.integration.wtp.ui_2.6.0.v20100617-1315.jar.pack.gz

The solution here is often simply to force p2 to pick a specific mirror rather than letting it choose any mirror it wants.

How, you ask?

Well, assuming you were polling this site looking for artifacts to install or update...

http://download.eclipse.org/birt/update-site/2.6/

... you would then change that URL to this, and look at the list of available mirrors:

http://www.eclipse.org/downloads/download.php?file=/birt/update-site/2.6/

Now it's a trivial matter to select a mirror that's close to you and try that instead of the download.eclipse.org mirror, such as:

ftp://mirror.csclub.uwaterloo.ca/eclipse/birt/update-site/2.6/

---

If you're running a Tycho build, this URL should be changed in your parent-pom.xml ...

<url>http://download.eclipse.org/birt/update-site/2.6/</url>

... or your .target platform file, depending on which way you're building.

<repository location="http://download.eclipse.org/birt/update-site/2.6/"/>

If you rely on a parent-pom.xml, make sure you're activating the profile with the revised URL...

mvn3 clean install -U -B -fae -Phelios

... or, if you're building against a .target platform file, make sure you update the URL in that file, and that your build points to the profile which will load the .target file.

mvn3 clean install -U -B -fae -P!helios,helios-no-target

UPDATE, 2010/08/11: Forgot to mention that there are a number of p2 update site zips available here to help with your offsite mirroring: http://download.eclipse.org/athena/repos/.

Blog comments or spam? No idea.

I don't speak Chinese. Or Korean. Or Japanese. I mention this because lately I've been getting a couple comments per post in a foreign character set, and I can't tell if it's spam or a legit comment.

Please, if you have something to say, stick to English, French, German, or Spanish. Hell, even Latin, lolcode, or twitterspeak. Anything other than that I'll just delete as spam.

kthxbai,

Nick

Update Site Aggregation: B3 vs. Tycho

Last year, I used to aggregate update sites with the Buckminster Aggregator, but since that won't install into Eclipse 3.6 (Helios), I had to migrate to the B3 Aggregator. This new version of the Aggregator is greatly expanded and worked fine until recently, when it has begun to suffer from a rather nasty p2 problem: instead of the Director just installing the aggregator into an Eclipse instance prior to then running the aggregation, I get "The copies of profile SDKProfile are not in sync," and the whole process dies. http://www.blogger.com/img/blank.gif

So, in order to find a workaround, I went back to Tycho, and discovered you can merge update sites with little more than two simple files:

• a site.xml, which lists the features to aggregate and how to categorize them, and
• a pom.xml to list the source sites and drive the aggregation.

Unfortunately the Tycho solution doesn't include the ability to add associate sites to the metadata after generation, but that can simply be done as a downstream step (Tycho can call Ant using the maven-antrun-plugin).

pogoplug network attached storage (NAS) for linux, mac, windows

A couple months ago I bought a PogoPlug. Because it's an ungodly pink colour and because I've been hella busy with other stuff, I finally unboxed it today, and discovered that while:

• it's a snap to configure through the web UI
• it works with ext3 and fat32 drives
• it's SSH accessible, and
• there are other installable linux apps for it

... setting it up for Linux was not entirely trivial.

While the above article helped, a couple points were not immediately obvious:

• If you mount the drive as root, it's not accessible as anyone else; if you mount as the user, not even root can read it.
• Use of a /etc/pogoplugfs.conf file is highly recommended, so that you can log in w/o having to key in your username and password every time. Create this file as root, and set it chmod 644 if not already:

  svcuser=you@email-provider.com
  svcpassword=web-login-password
  logseverity=10

• To automount the drive on startup (eg., on my old xubuntu 6 system), as root, try creating a new file, /etc/init.d/pogoplug:

  #! /bin/sh
  ### BEGIN INIT INFO
  # Provides:          
  # Required-Start:    $remote_fs $syslog
  # Required-Stop:     $remote_fs $syslog
  # Should-Start:      $named
  # Default-Start:     2 3 4 5
  # Default-Stop:      1
  # Short-Description: pogoplug fs mount as myusername
  # Description:       pogoplug fs mount as myusername
  ### END INIT INFO
  
  sudo -u myusername /usr/bin/pogoplugfs --mountpoint /media/pogoplug
  
  exit 0

• Then, to activate this file, as root:

  chmod +x /etc/init.d/pogoplug; \
  for x in 2 3 4 5; do \
    cd /etc/rc${x}.d; ln -s /etc/init.d/pogoplug S99pogoplug; \
  done

With Fedora 12, I could simply create a startup task using System < Preferences < Startup Applications from the gnome menu.