public Builder addReadinessFutures(
            String name,
            Map<Endpoint, ? extends CompletionStage<?>> newFutures
        ) {
            newFutures.forEach((endpoint, future) -> endpointStages.computeIfAbsent(endpoint, __ -> new ArrayList<>()).
                add(new EndpointCompletionStage(name, future)));
            return this;
        }
Add readiness futures for individual endpoints.

@param name          The future name.
@param newFutures    A map from endpoints to futures.

@return              This builder object.
server-common/src/main/java/org/apache/kafka/server/network/EndpointReadyFutures.java