About Question enthuware.ocpjp.v8.2.1106 :

[UncleF]

This question is from 1Z0-813 exam objectives.
Lock,ReadWriteLock and ReentrantLock are not part of 1Z0-809 exam.

[admin]

This topic is not explicitly listed in 809 objectives but some candidates have reported getting questions on it. For this reason we have kept a few (only 3, actually) similar questions in the question bank.

The problem with the official objectives is that in some cases they are quite detailed but in others they don't list out each and every class. So we don't rely only on the objectives.

HTH,
Paul.

[UncleF]

Thank you for your reply.
This was very interesting topic anyways. And very useful IRL, especially ReentrantReadWriteLock.