Hystrix Parallel Command Execution

            final List<Future<UserProfile>> futures = userIds.stream().distinct().filter(Objects::nonNull)
                    .map(id -> new GetUserProfileCommand(registry, authToken, id, roleMap).queue())
                    .collect(Collectors.toList());

            return futures.stream().parallel()
                    .map(f -> {
                        try {
                            return f.get();
                        } catch (InterruptedException | ExecutionException e) {
                            return null;
                        }
                    })
                    .filter(Objects::nonNull)
                    .collect(Collectors.toConcurrentMap(UserProfile::getUserId, profile -> profile));