public EntityIdSet<Stream> obtainStreamIdSet() {
        if (streamIdSet == null) {
            streamIdSet = new EntityIdSet<>();
        }
        return streamIdSet;
    }
You must use setFeeds() instead this is here for compatibility with
previous versions.
stroom-legacy/stroom-legacy-model_6_1/src/main/java/stroom/legacy/model_6_1/OldFindStreamCriteria.java