Can someone tell me how to create in java an array of n number of threads in a thread group?

Question

I've been trying for some time to find some examples or explenations of java how to create an array of n threads that are part of some threadgroup, so if anyone knows something more please explain, thanks.

Answer 1

Why use ThreadGroup at all? Do you actually need it? Maybe all you really need is an ExecutorService that you can submit your runnables and callables to.

Being new, you might also want to take a look at Callable. It's almost like a thread, except a Callable returns a value. When you submit a callable, you get back a Future object, which is like a promise to get the value from the callable.

Answer 2

Sure. You can instantiate a ThreadGroup and just pass it into the Thread constructor:

  ThreadGroup threadGroup = new ThreadGroup("somename");
  Thread[] threads = new Thread[10];
  for (int i = 0; i < threads.length; i++) {
      threads[i] = new Thread(threadGroup, someRunnable);
  }
  ...