@Override
  public Parameters getParameters() {
    return new LegacyProtoParametersNotForCreation(
        serialization.getTypeUrl(), serialization.getOutputPrefixType());
  }
Returns a LegacyParametersNotForCreation object.

<p>Note: this is different from the {@code LegacyProtoParameters} object which was used to
create this key. One cannot use the returned object to create a new key.
java_src/src/main/java/com/google/crypto/tink/internal/LegacyProtoKey.java