Worse example of security immaturity will be hard to find!

The author obviously doesn't know neither crypto nor secure programming, as he introduces some very bad practices!

He also more or less just gives the API some fairy-tale rationale and demonstrates a profound non-understanding of security issues and especially cryptology.

It's reading books like this that produces idiots to security programmers…

Avoid at all costs. If you need some information on Java's crypto API, you'll get more info out of the standard manual.