public Optional<VALIDATOR_SELECTION_MODE> getValidatorSelectionMode() {
    final Optional<String> mode = JsonUtil.getString(forkConfigRoot, VALIDATOR_SELECTION_MODE_KEY);
    return mode.flatMap(
        m ->
            Arrays.stream(VALIDATOR_SELECTION_MODE.values())
                .filter(v -> v.name().equalsIgnoreCase(m))
                .findFirst());
  }
Gets validator selection mode.

@return the validator selection mode
config/src/main/java/org/hyperledger/besu/config/QbftFork.java