ControllerResult<Map<String, ApiError>> updateFeatures(
        Map<String, Short> updates,
        Map<String, FeatureUpdate.UpgradeType> upgradeTypes,
        boolean validateOnly
    ) {
        TreeMap<String, ApiError> results = new TreeMap<>();
        List<ApiMessageAndVersion> records =
                BoundedList.newArrayBacked(MAX_RECORDS_PER_USER_OP);
        for (Entry<String, Short> entry : updates.entrySet()) {
            results.put(entry.getKey(), updateFeature(entry.getKey(), entry.getValue(),
                upgradeTypes.getOrDefault(entry.getKey(), FeatureUpdate.UpgradeType.UPGRADE), records));
        }

        if (validateOnly) {
            return ControllerResult.of(Collections.emptyList(), results);
        } else {
            return ControllerResult.atomicOf(records, results);
        }
    }
Gives information about the supported versions in the cluster.
metadata/src/main/java/org/apache/kafka/controller/FeatureControlManager.java