wait(), notify(), notifyAll() - Why in Object class?

Why in Object class?

Because these methods are used for Inter-thread communication and depend on the Monitor (Lock) associated with every object in Java. Every object serves as a lock/monitor, so the methods belong to the Object class.

Key Rules:

• Must be called from a synchronized context.
• wait() releases the lock and enters the waiting state.
• notify() wakes up a single random thread waiting on the object's monitor.
• notifyAll() wakes up all threads waiting on the object's monitor.