private void sortFieldListAndCachePositions() {
        // de-dup the list
        Set<StatisticField> tempSet = new HashSet<>(statisticFields);
        statisticFields.clear();
        statisticFields.addAll(tempSet);
        tempSet = null;

        Collections.sort(statisticFields);

        fieldPositionMap.clear();
        int i = 0;
        for (final StatisticField field : statisticFields) {
            fieldPositionMap.put(field.getFieldName(), i++);
        }
    }
Held in a set to prevent duplicates.
<p>
XMLTransient to force JAXB to use the setter
stroom-legacy/stroom-legacy-model_6_1/src/main/java/stroom/legacy/model_6_1/StroomStatsStoreEntityData.java