Open source projects with Java and Scala interaction

I'm going to give a talk about using Java and Scala together and I want to investigate some projects (large and small) which contains Java and Scala code.

If you know links to correspondent projects post th开发者_开发百科em here.

This page on the Scala wiki is a good starting point...

The various scala testing frameworks come to mind. They all have some integration with JUnit or TestNG

Gimd is one example of small project: http://code.google.com/p/gimd/

Although development stalled for a while because I'm busy with other duties it already contains some examples of Scala<->Java integration. Notably:

• unit tests are written using junit
• Gimd is using JGit (library in Java) as underlying layer

While working on Gimd I found that using Java from Scala is mostly easy and seamless the contrary is not always true. It's not really a fault of Scala as it's simple manifestation that Java is a less expressive language.

Unfortunately I don't know any open source project but I have worked on very large projects over the last few years that have java and scala interacting and my experience has been mostly very positive. If I had one piece of advice it would be to use scala-javautils. It's a life saver and is far better than the scala jcl code. Before we started using it trying to get some interactions involving collections was heart-breaking. However I'm led to believe 2.8 will solve this.

In general I find the interactions between scala and java very close to using one language.