Whirr currently provides a Java API for running services. There is not much documentation available for it yet, so the best way to use it is to look at the Hadoop and ZooKeeper unit tests, which show how to start and stop clusters.
Building from source
First, you need to build RAT since they have not had a release yet.
$ svn co http://svn.apache.org/repos/asf/incubator/rat/main/trunk/ rat-trunk $ cd rat-trunk; mvn install
Now we can build Whirr:
$ svn co https://svn.apache.org/repos/asf/incubator/whirr/trunk/ whirr-trunk $ cd whirr-trunk; mvn compile jar:jar