V - The result type returned by this Future's get methodRunnableScheduledFuture<V>FutureTaskpublic interface RunnableFuture<V> extends Runnable, Future<V>
Future that is Runnable. Successful execution of
the run method causes completion of the Future
and allows access to its results.FutureTask,
Executorvoid run()
run 在接口中 RunnableThread.run()