static public void validateThatLeafGroupsCountIsAFactorOfRedundancy(int totalRedundancy, int subGroups) {
        if (totalRedundancy % subGroups != 0) {
            throw new IllegalArgumentException("Expected number of leaf groups (" +
                                               subGroups + ") to be a factor of redundancy (" +
                                               totalRedundancy + "), but it is not");
        }
    }
Class used to validate that hierarchic distribution is correctly setup when having an indexed content cluster.

Note that this class does not implement the com.yahoo.vespa.model.application.validation.Validator interface,
but is instead used in the context of com.yahoo.vespa.model.ConfigProducer.validate() such that it can be unit tested
without having to build the complete vespa model.

@author geirst
config-model/src/main/java/com/yahoo/vespa/model/content/IndexedHierarchicDistributionValidator.java