common interface for BatchInserter and GraphDatabaseService?

[ehx-v1]

I think as they both have the shutdown() method, there might be a common interface defining shutdown() that would make some support code I'm making fairly more general, because I have a class wrapping BatchInserters (so far) which is an AutoCloseable and calls shutdown() in its close(), thus mediating between BatchInserters and try-with-resource it would be really nice if that could be generalized to the interface providing shutdown() if there is such