Notify not getting the thread out of wait state

Question

I am trying to use 2 threads. 1 thread prints only odd number and the other thread prints only even number and It has to be an alternative operation.

Eg:

Answer 1

You have a real confusion of threads and locks. I suggest you create one and only one object to use for locking to start with as you don't appear to have a clear idea what you are locking.

If you notify() and nothing is listening, the signal is lost. However, a wait() can wake spuriously.

For this reason, a notify() should be accompanied by a state change and a wait() should be in a loop checking that change.