Why this InnerThread isn't working properly?

Question

There is no error in this InnerThread program. But the problem is Thread should work one by one. One will put the value and then another will get value. But sometime put operation working two times in a row. Like...
Put 0
Get 0
Put 1
Put 2
Get 1
Put 3
Get 2
So on...

I already used wait() , notify(), synchronised method but didn’t worked.
Here is the code👇
https://code.sololearn.com/ctKxpRr95419/?ref=app
T.I.A

Answer 1

Check this now, I made a few changes to your code and now its working. I only used notify and wait, nothing fancy. See comments in code and also a link to baeldung article that has the whole concept explained in detail.

https://code.sololearn.com/ciexEj7Ck6Tj/?ref=app

Answer 2

Thread.sleep() is not very exact with the wait time, and depends on the operating system's task scheduler to continue the program flow. Therefore your paralel threads may be "racing" and one of them could get ahead.
To control the access to the shared resource (Q) you need to apply some locking mechanism, maybe look at Semaphore
https://www.geeksforgeeks.org/semaphore-in-java/

Answer 3

Tibor Santa
Thank you so much It's working.😉

Answer 4

Mirielle[Inactive] run this code on Netbeans or Eclipse.
Sl code playground have limited execution time.
But sometime put operation occurring after 10, 20 times.

Answer 5

Tibor Santa It's not working, the reason is Semaphore used for multiple threads but it will first done one thread completely then moves to another. But I want, put will set the value and get should achieve that after putting. put, get....... this operation will continue until I stop the execution.