Not a single mention of Guice or even dependency injection? Seems like a gaping omission in a guide that claims to be about "modern" Java.
Dependency injection is an abomination. Working on DI code feels like slogging through the post-processed expansion of some more elegant language. It's hard to understand control flow, and DI adds exciting failure modes to otherwise-correct code. Don't forget that DI also bloats class and method counts. Substitution for testability should be done at the runtime level, substituting class references as needed, instead…
> Substitution for testability should be done at the runtime level, substituting class references as needed
That would require a Java agent. And that's a smell it its own right. (Cf JMockit)