@Override public Collection<MessageReceiver> getMembers() { PermissionService service = Sponge.getGame().getServiceManager().provideUnchecked(PermissionService.class); return service.getKnownSubjects().values().stream() .flatMap(input -> input.getAllWithPermission(this.permission).entrySet().stream() .filter(Map.Entry::getValue) .map(entry -> entry.getKey().getCommandSource().orElse(null)) .filter(source -> source != null)) .collect(GuavaCollectors.toImmutableSet()); }