private static String outputPrefixToString(OutputPrefixType outputPrefixType) {
    switch (outputPrefixType) {
      case TINK:
        return "TINK";
      case LEGACY:
        return "LEGACY";
      case RAW:
        return "RAW";
      case CRUNCHY:
        return "CRUNCHY";
      default:
        return "UNKNOWN";
    }
  }
returns the serialization which was used to create this object.
java_src/src/main/java/com/google/crypto/tink/internal/LegacyProtoParameters.java