There's a world of difference between a well-written, well-edited book and SEO spam. The latter is not making a genuine attempt to actually teach you, that's not the point.
If you grabbed a 'Java Basics' book, you would not expect the author to explain the entire implementation details of ArrayList before telling them about for-each.
But somehow the author of this article thinks that this kind of unnecessary level of detail is appropriate.
It does not look like SEO spam to me. The site seems actually nice and well produced.
I may be missing something, thou. Why is that page so bad that the author does not want it in the list of results?