docs: public static <T, U extends T> CompletableFuture<T> toJava(Future<U> scalaFuture) {
  		final CompletableFuture<T> result = new CompletableFuture<>();
  
  		scalaFuture.onComplete(new OnComplete<U>() {
  			@Override
  			public void onComplete(Throwable failure, U success) {
  				if (failure != null) {
  					result.completeExceptionally(failure);
  				} else {
  					result.complete(success);
  				}
  			}
  		}, Executors.directExecutionContext());
  
  		return result;
  	}