public static void register(MutableSerializationRegistry registry)
      throws GeneralSecurityException {
    registry.registerParametersSerializer(PARAMETERS_SERIALIZER);
    registry.registerParametersParser(PARAMETERS_PARSER);
    registry.registerKeySerializer(KEY_SERIALIZER);
    registry.registerKeyParser(KEY_PARSER);
  }
Methods to serialize and parse {@link HmacPrfKey} objects and {@link HmacPrfParameters} objects.
java_src/src/main/java/com/google/crypto/tink/prf/internal/HmacPrfProtoSerialization.java