Utility of Future.cancel(boolean) method

Question

I was simply exploring the java.util.concurrent package.

I learnt that the class \'Future\' has a method boolean cancel(boolean mayInterrupt

Answer 1

How does wrapping a Callable in a FutureTask help if the Thread can't be stopped by cancel?

You want to cancel the task, not the thread running it. Using cancel(true) prevents the task from starting (but doesn't remove it from the queue) and interrupts the thread if the task has started. The Task can ignore the interrupt, but there is no clean way of killing a thread without killing the whole process.