@Override
    public boolean equals(Object other) {
        if (other instanceof SummaryElementsSelector o) {
           return select.equals(o.select) && summaryFeature.equals(o.summaryFeature);
        } else {
            return false;
        }
    }
A class selecting which summary elements of a multi-value field to render.
config-model/src/main/java/com/yahoo/vespa/documentmodel/SummaryElementsSelector.java