public DimensionalMap<VALUE> build() {
            Map<CompoundName, DimensionalValue<VALUE>> map = new HashMap<>();
            for (Map.Entry<CompoundName, DimensionalValue.Builder<VALUE>> entry : entries.entrySet()) {
                map.put(entry.getKey(), entry.getValue().build(entries));
            }
            return new DimensionalMap<>(map);
        }
Returns true if this is empty for all contexts.
container-search/src/main/java/com/yahoo/search/query/profile/compiled/DimensionalMap.java