Support for java 8 will come with jack & jill. It might also need a new API level (24 ? ), which would seriously hamper its adoption. This is why many people see kotlin as a great thing for the future of Android (even though kotlin on android could also benefit from java 8 as a target)

You can use a good number of these today with Retrolambda: https://github.com/orfjackal/retrolambda