@Override
    public Optional<ServerPlayer> resolvePlayer() {
        if (!Sponge.isServerAvailable()) {
            return Optional.empty();
        }

        return Sponge.server().player(this.parent.getUniqueId());
    }
Implements {@link LPSubject} for a {@link SpongeUser}.
sponge/src/main/java/me/lucko/luckperms/sponge/service/model/permissionholder/UserSubject.java