Scala, Concurrency, API, Project Loom, Java.
Thread.sleep(1000) println("f2 complete") } Thread.sleep(500) println("f1 complete") f2 } f1.join().join() } Such nesting is, of course, allowed, and the above code (as you might expect or not) prints f1 complete followed by f2 complete. Even though f2 is nested within f1, it won't be interrupted