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Why is wait notify and notifyAll in the object class?
If wait() and notify() were on the Thread instead then each thread would have to know the status of every other thread and there is no way to know thread1 that thread2 was waiting for any resource to access. Hence, notify, wait, notifyAll methods are defined in object class in Java.
When wait () notify () notifyAll () methods are called does it releases the lock or holds the acquired lock?
8 Answers. Show activity on this post. No — notify / notifyAll don’t release locks like wait does. The awakened thread can’t run until the code which called notify releases its lock.
What is the difference between notify and notifyAll in Java?
In case of multiThreading notify() method sends the notification to only one thread among the multiple waiting threads which are waiting for lock. While notifyAll() methods in the same context sends the notification to all waiting threads instead of single one thread.
What is true about acquiring object lock before calling wait notify and notifyAll?
Threads doesn’t have own stack. What is true about acquiring object lock before calling wait(), notify() and notifyAll()? b. If we call wait(), notify() and notifyAll() methods without acquiring object lock i.e. from outside synchronize block then java.
Does wait method release lock?
The wait function doesn’t release “all locks”, but it does release the lock associated with the object on which wait is invoked.
What is notifyAll?
notifyAll() wakes up all threads that are waiting on this object’s monitor. A thread waits on an object’s monitor by calling one of the wait methods. The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object.
What is notifyAll in Java?
notifyAll() wakes up all threads that are waiting on this object’s monitor. A thread waits on an object’s monitor by calling one of the wait methods.
Can Wait () be overridden?
Ans. wait and notify are declared final in object class and hence cannot be overridden.
Is it important to acquire object lock before calling wait () notify () and notify all ()?
If no threads are waiting in the waiting queue, then notify() and notifyAll() have no effect. Before calling the notify() or notifyAll() method of an object, a thread must own the lock of the object. Hence it must be in one of the object’s synchronizedmethods or synchronized block.
How does object Wait work?
wait() causes current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object. In other words, this method behaves exactly as if it simply performs the call wait(0). The current thread must own this object’s monitor.