_controllerContextMap = accessor.getChildValuesMap(keyBuilder.controllerContexts());
// Read all single properties together
List<HelixProperty> singleProperties =
accessor.getProperty(ImmutableList.of(keyBuilder.clusterConfig(),
keyBuilder.controllerLeader(), keyBuilder.pause()));
_clusterConfig = (ClusterConfiguration) singleProperties.get(0);
if (_clusterConfig != null) {
_idealStateRuleMap = _clusterConfig.getIdealStateRules();
} else {
_idealStateRuleMap = Collections.emptyMap();