http://docs.mongodb.org/ecosystem/drivers/java/
JavaScript (Rhino) section lists a seemingly stale project for calling MongoDB through Rhino on the JVM using a distinct API. A new project exists, which now has it's first release in the maven central dependency repository. This project's stated aim is to provide support for the official MongoDB JavaScript API within the Rhino runtime on the JVM.
The project is called Horn of Mongo, https://github.com/nlloyd/horn-of-mongo.
This would be a good project to add to the java drivers ecosystem page.