I'm trying to quickly find as much about the Validator interface as possible. The first reference to anything related in the index is pg. 468, but actually on p. 463 it is stated:

"You've seen the notion of a Validator earlier in this book"

Where please? Thanks in advance.

ok on p. 468 it says "Validators are ... explained in more detail in Chapter 3." I supposed that wouldn't be a bad chapter to read in its entirety, except that I've read lots of this sort of stuff before, and just want specific information about validators. If an author, or someone else intimately familiar with this book, is monitoring this message board, please can you tell me more specifically where in this book I can read about validators. Or could somebody send me chapter 3 as a PDF so I can search it myself; to tell you the truth this might be a better sample chapter PDF than chapter 1 anyway.