Saturday, June 29, 2013

New Android tooling with gradle: Order matters

I am trying to convert RHQPocket over to use the new Android build system with Gradle.
The documentation is comprehensive, but as always does not exactly match what I have in front of me.

After moving the sources around I started generating a build.gradle file. I added my external libs to the dependencies but the build did not succeed with a lot of trial and error.

At the end with the help of googling and StackOverflow I found out that order matters a lot in the build file:

First comes the section about plugins for the build system itself:

buildscript {
repositories {

dependencies {
classpath ''

Settings herein only apply to the build system, but not to the project to be built.

After this we can use those plugins (the android one)

apply plugin: 'android'
apply plugin: 'idea'

And only when those plugins are loaded, we can start talking about the project itself and add dependencies

repositories {
dependencies {
compile 'org.codehaus.jackson:jackson-core-asl:1.9.12'
compile 'org.codehaus.jackson:jackson-mapper-asl:1.9.12'

android {
compileSdkVersion 17
buildToolsVersion "17.0"

I guess for someone experienced with Gradle, this is no news, but it took me quite some time to figure out especially as the documentation mentions all the parts but not on a larger example.

The file layout now looks like this:

Bildschirmfoto 2013 06 29 um 22 07 02

One caveat is that the external libraries are not automagically yet loaded into the IDE - one still has to manually add them in the project structure wizard.

The last thing is then to mark build/source/r/debug as source directory to also get completion for the R.* entries.

Tuesday, June 25, 2013

RHQ 4.8 released

RHQ 4.8 has been released with another batch of new features and bug fixes.
Major changes since RHQ 4.7 are
  • New storage backend for metrics based on Cassandra:

    Numerical metric data is now stored in a Cassandra cluster to improve scalability for larger deployments with many metrics.
    Architecture overview cassandra color

    The intention is to move more mass data into Cassandra into the future (events, calltime data etc). We just had to start somewhere. If you are upgrading from an earlier version of RHQ, a utility to migrate metrics gathered is provided.
  • More improvements to the new charts
    Bildschirmfoto 2013 06 25 um 10 57 07

    The selection of the time period has been changed:
    • There is now a button bar at the top to quickly select the timeframe to display
    • If you hover with the mouse between two "bars" you will see a little crosshair, that starts the
      selection mode - drag it over a series of bars to zoom in. Mike Thompson has created a YouTube video that explains this.
  • New installation process:

    With the above change of the backend storage, we have changed the installation process again to reduce the complexity to install RHQ. The new process basically goes:
    • unzip
    • cd rhq-server-4.8.0
    • edit bin/
    • bin/rhqctl install (--storage-data-root-dir=<some directory>

    For upgrades the process is very similar: you run unzip the new binaries and then run bin/rhqctl upgrade --from-server-dir=<old server>
    Please consult the installation and upgrade guides before starting.
  • REST-api is now (mostly) stable and supports paging on (some) resources. The documentation is also up on SourceForge and the rhq-samples project has a special section on examples for the REST-api.

As always there have been many more smaller improvements and bug fixes - many thanks to everyone who has contributed via bug report, comments, discussions on #rhq and/or via code contributions.

Please check the full release notes for details. They also contain a list of commits.

RHQ is an extensible tool to monitory your infrastructure of machines and applications, alert operators on user defined conditions, configure resources and run operations on them from a central web-based UI. Other ways of communicating with RHQ include a command line interface and a REST-api.

You can download the release from source forge.

As mentioned above, the old installer is gone, so make sure to read
the wiki document describing how to use the new installer.

Maven artifacts are available from the JBoss Nexus repository and should also be available from Central.

Please give us feedback, be it in Bugzilla, Mailing lists or the forum. Or just join us on IRC at

And as I have been asked recently: yes we are happy to accept code contributions -- be it for the RHQ core, as well as plugins or for the samples project. Also if you e.g. have written a plugin, share a pointer to it, which we can then share on the wiki etc.