Project Jigsaw: Early-Access Builds
If you'd like to try out the EA builds, by far the most helpful things you can do are:
Try to run existing applications, without change, on these builds to see whether the module system, or the modularization of the platform, breaks your code or identifies code that depends upon JDK-internal APIs or other unspecified aspects of the platform.
Experiment with the module system itself, perhaps by following the quick start guide, and start thinking about how to migrate existing libraries and application components to modules. We hope to publish some specific migration tips shortly.