I'm reading the new printing of "The Complete
Java 2 Certification Study Guide". It seems flawless so far - I've finished chapter two. I've also picked up a few details along the way. Just studying for the
test is worthwhile.
The tests at the end of each chapter can be rather humbling. A developer I know thinks he's a decent Java programmer and he tried the first five questions. After getting only one right, he gave up.