multithreading - Is Java thread id unique across multiple thread pools?

Question

I have multiple thread pools running each with 4 threads. Each thread locks some common resource based on a unique ID they provide. I am using Thread.currentThread().getId() as unique ID to lock and release resources.

I read in Thread class that thread ID is just a long number that is incremented and allocated, also it may be reused once a thread is terminated. But it does not mention anything regarding its behavior in thread pools.

Is the thread ID guaranteed to be unique among threads that are part of different thread pools?

question from:https://stackoverflow.com/questions/66057480/is-java-thread-id-unique-across-multiple-thread-pools

Answer 1

Thread ID is unique; but you need to beware that once the thread terminates JVM may reuse the thread ID.

https://docs.oracle.com/javase/8/docs/api/java/lang/Thread.html#getId--