Threads - notify() and notifyAll() methods

• the notify() and notifyAll() methods are defined in the Object class
• they can only be used within synchronized code
• notify() wakes up a single thread which is waiting on the object's lock
• if there is more than one thread waiting, the choice is arbitrary ie there is no way to specify which waiting thread should be re-awakened

• notifyAll() wakes up ALL waiting threads; the scheduler decides which one will run

• if there are no waiting threads, the notifys are forgotten
• only notifications that occur after a thread has moved to wait state will effect it; earlier notifies are irrelevant