code: public static <T> Future<T> of(final Supplier<T> s, final Executor ex) {
          return Future.of(CompletableFuture.supplyAsync(s, ex));
      }
docs: Create a Future object that asyncrhonously populates using the provided
  Executor and Supplier
  
  @param s
  Supplier to asynchronously populate results from
  @param ex
  Executro to asynchronously populate results with
  @return Future asynchronously populated from the Supplier