public boolean isZero() {
            return mapsDeletedCount == 0
                   && valuesDeletedCount == 0
                   && valuesDeReferencedCount == 0;
        }
For use in testing at SMALL scale. Dumps the content of each DB to the logger.
stroom-pipeline/src/main/java/stroom/pipeline/refdata/store/offheapstore/RefDataOffHeapStore.java