It looks like the documentation is here: http://docs.rosjava.googlecode.com/hg/android_core/html/building.html
Or, as it currently says:
roscd android_core
rosrun rosjava_bootstrap install_generated_modules.py android_tutorial_pubsub
./gradlew android_tutorial_pubsub:debug
But I'm getting the following errors:
[ bowie:~/versioned/ros/3rd_party/android_core ] ./gradlew android_tutorial_pubsub:debug
:android_gingerbread:deployTransitiveLibs
FAILURE: Build failed with an exception.
* What went wrong:
Could not resolve all dependencies for configuration ':android_gingerbread:compile'.
> Could not find group:ros.rosjava_core, module:apache_xmlrpc_client, version:0.0.0-SNAPSHOT.
Required by:
ros.android_core:android_gingerbread:0.0.0-SNAPSHOT > ros.rosjava_core:rosjava:0.0.0-SNAPSHOT
> Could not find group:ros.rosjava_core, module:apache_xmlrpc_server, version:0.0.0-SNAPSHOT.
Required by:
ros.android_core:android_gingerbread:0.0.0-SNAPSHOT > ros.rosjava_core:rosjava:0.0.0-SNAPSHOT
> Could not find group:ros.rosjava_core, module:apache_xmlrpc_common, version:0.0.0-SNAPSHOT.
Required by:
ros.android_core:android_gingerbread:0.0.0-SNAPSHOT > ros.rosjava_core:rosjava:0.0.0-SNAPSHOT
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
BUILD FAILED
I've filed a ticket here: http://code.google.com/p/rosjava/issues/detail?id=93
It looks like you need to also run the following commands:
roscd rosjava_core
./gradlew rosjava:install
./gradlew apache_xmlrpc_common:install
./gradlew apache_xmlrpc_server:install
./gradlew apache_xmlrpc_client:install
./gradlew rosjava_tutorial_pubsub:install
Then you need to update the android project for your SDK:
roscd android_gingerbread
$ANDROID_SDK/tools/android update project -p `pwd`
Then you need to install ant1.8 if you don't have it (I didn't on 10.04)
sudo apt-get install ant1.8 ant1.8-optional
Then you should be able to build the example.
roscd android_tutorial_pubsub
../gradlew debug