private static RoutingMethod routingMethodFrom(LbServicesConfig.Tenants.Applications.Endpoints endpoint) {
        if (endpoint.routingMethod() == sharedLayer4)
            return RoutingMethod.sharedLayer4;

        throw new IllegalArgumentException("Unhandled routing method: " + endpoint.routingMethod());
    }
Returns a copy of this containing only endpoints using given routing method
routing-generator/src/main/java/com/yahoo/vespa/hosted/routing/RoutingTable.java