Attribute Dictionary & V4.0

[Cantor, Scott]

> So "all" we need to do in V4.0.0 is to define precisely what the
> AttributeDictionary does.  A start point will be "resolvers for everything
> currently inside the AttributeDefinition".

I hesitate to simplify it to that degree because I have a tendency to want to turn everything into service abstractions like that, but that's pretty much my mental model, yes.

> What's not obvious to me is how we wide this Interface in V4 without changing
> the API.

Not sure I follow that.

As a general matter, the main trick Java 8 added is that you can now add methods to interfaces that have default implementations so it's possible to compatibly change them in some cases without breaking anybody's code. They're just gradually turning it into a multiple inheritance language without actually coming out and saying it, but I don't think it's meant to be good practice to bury lots of implementation code in interfaces, it's just a tool to make evolving APIs a bit more tractable.

-- Scott