Java - relationship between threads and CPUs

Question

I am pretty new to multithreading, and I am working on a project where I am trying to utilize 4 CPUs in my Java program. I wanted to do something like

int numP         


        

Answer 1

no it won't guarantee anything about where the threads run

in fact the OS thread scheduler is free to migrate threads around cores as it sees fit (so one line you could be on core 0 and the next on core 4)

you could set the affinity of threads but this is not available in java directly (AFAIK)