@Override
        protected void getSearchChainsConfig(FederationConfig.Target.Builder tB) {
            tB.searchChain(searchChainConfig.getSearchChainConfig());
        }
One or more search chains that are handled as a single group,
which can be federated to as a single entity.
config-model/src/main/java/com/yahoo/vespa/model/container/search/searchchain/FederationSearcher.java