During the last weeks there were still a lot of movement and changes in the API and package structure, but big changes have calmed down lately, so that I decided to publish a first beta release 0.1.0.
I want to use Semantic Versioning for this library, hence a 0.1.0 release "is for initial development. Anything may change at any time. The public API should not be considered stable."
Babbler meanwhile supports a lot of extensions. I consider most of them quite stable, also some of them (like XEP-0060 Publish-Subscribe) need more work and improvement.
The meanwhile more than 600 units tests ensure software quality.
I've also put some work into implementing SCRAM-SHA-1 authentication, which isn't available out of the box in Java, but is required by XMPP (interoperability tests against server implementations must still be done).
Besides for the omnipresent need for good documentation, I am planning to implement XEP-0045: Multi-User Chat and maybe XEP-0301: In-Band Real Time Text as next (big) extensions for the future, while also keep working on PubSub/PEP and refining some other areas.
One thing I've also thought about is, that one could split the project up into different libraries, because all the plain simple "XML Schema implementations" or e.g. the JID implementation could also be reused by a server implementation. But that's also something which can be considered in the future.If you have any suggestions or ideas for improvement, let me know, they are highly appreciated!