struct String
    {
        using CppType = std::string;
        using JniType = jstring;

        using Boxed = String;

        static CppType toCpp(JNIEnv* jniEnv, JniType j)
        {
            assert(j != nullptr);
            return jniUTF8FromString(jniEnv, j);
        }

        static LocalRef<JniType> fromCpp(JNIEnv* jniEnv, const CppType& c)
        {
            return {jniEnv, jniStringFromUTF8(jniEnv, c)};
        }
    };