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What is a Livelock scenario in java?



Image by Clker-Free-Vector-Images from Pixabay


Livelock is a scenario in which two or more block each other by responding to an action caused by another thread.

In a deadlock situation, two or more threads wait in one specific state.

In a Livelock scenario, two more threads change their state in such a way that it prevents progress on their regular work.

E.g. Consider a scenario in which two threads try to acquire two locks. 

They release a lock that they have acquired when they cannot acquire the second lock.

In a Livelock situation, both threads concurrently try to acquire the locks. 

Only one thread would succeed, the second thread may succeed in acquiring the second lock.

Now both threads hold two different locks. And both threads want to have both locks. 

So they release their lock and try again from the beginning. This situation keeps repeating multiple times.

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