It's a beginner's book. Since I don't consider a real beginner is a release-minded student just yet, I downplay most opportunities to refer to Java 5, 6, or 7. The text focusses on "the now," if you will. After I suggest installing Java SE 7 -- so all the examples will work without a hitch -- there's not much more said about specific releases.
Make visible what, without you, might perhaps never have been seen. - Robert Bresson