@Override
  public int hashCode() {
    return Objects.hash(
        Arrays.hashCode(mode),
        Arrays.hashCode(kemId),
        Arrays.hashCode(kdfId),
        Arrays.hashCode(aeadId));
  }
Helper class for identifying different test cases.
java_src/src/main/java/com/google/crypto/tink/testing/HpkeTestId.java