I am setting up Sonar for one of my projects which is a mix of Groovy and Java. I am able to configure the project separately for eith
Sonar
Groovy
Java
UPDATE April 14th, 2014:
Starting with SonarQube 4.2, multi-language projects are supported.
This automatically happens when sonar.language is not set.
sonar.language
See my sample project here: https://github.com/bellingard/multi-language-project