Java: Nested synchronization blocks

Question

I saw this in one of Heinz Kabutz\'s Java Specialist newsletter editions and, although the rest (and indeed, all) of Dr. Kabutz\'s articles are well-explained and d

Answer 1

According to Nested Monitor Lockout Tutorial

In nested monitor lockout, Thread 1 is holding a lock A, and waits for a signal from Thread 2. Thread 2 needs the lock A to send the signal to Thread 1. While in deadlock, two threads are waiting for each other to release locks.

Deadlock might be analogous to two persons are imprisoned in two rooms, they want to make a switch to the other's room but both of them only have their counterpart's key. While nested monitor lockout just like the boss is arranged to sleep in a room and suppose he'll be waked up only when someone comes in the room. And the secretary is responsible for waking up his boss. But the boss still hold the key to the room when slept, so the secretary could not come in to wake him up.