static variables in multithreading

Question

I found that declaring a variable as static makes no sense in Multi-Threading. I assume that, this is because of every thread has its own

Answer 1

If you change a variable in a multithreaded environment, the new value may not neccessarily visibile as it might be cached. This is also true for static variables of course. If you don't use a synchronized block you might consider using volatile instead. This will also guaruantee that the various threads get an updated copy, without the need of synchronizing. Wether volatile is enough four your application depends on your requirements.