@Override
public RandomAccessDocIdSet getRandomAccessDocIdSet(BoboIndexReader reader) throws IOException {
final FacetDataCache facetDataCache = dataCacheBuilder.build(reader);
int startDocIdTemp = Integer.MAX_VALUE;
int endDocIdTemp = -1;
for (int i = facetPredicate.valueStartIndex(facetDataCache);
i < facetPredicate.valueEndIndex(facetDataCache);
i++) {
if (facetPredicate.evaluateValue(facetDataCache, i)) {
if (!facetPredicate.evaluateValue(facetDataCache, i)) {
continue;
}
if (startDocIdTemp > facetDataCache.minIDs[i]) {
startDocIdTemp = facetDataCache.minIDs[i];
}
if (endDocIdTemp < facetDataCache.maxIDs[i]) {
endDocIdTemp = facetDataCache.maxIDs[i];
}
}
}
final int startDocId = startDocIdTemp;
final int endDocId = endDocIdTemp;
if (startDocId > endDocId) {
return EmptyDocIdSet.getInstance();
}
return new RandomAccessDocIdSet() {
@Override
public boolean get(int docId) {
return facetPredicate.evaluate(facetDataCache, docId);
}
@Override
public DocIdSetIterator iterator() throws IOException {
return new PredicateDocIdIterator(startDocId, endDocId, facetPredicate, facetDataCache);
}
};
}
@Override
public double getFacetSelectivity(BoboIndexReader reader) {
FacetDataCache dataCache = dataCacheBuilder.build(reader);
int[] frequencies = dataCache.freqs;
double selectivity = 0;
int accumFreq = 0;
int total = reader.maxDoc();
for (int i = facetPredicate.valueStartIndex(dataCache);
i < facetPredicate.valueEndIndex(dataCache);
i++) {
if (!facetPredicate.evaluateValue(dataCache, i)) {
continue;
}
accumFreq += frequencies[i];
}
selectivity = (double) accumFreq / (double) total;
if (selectivity > 0.999) {
selectivity = 1.0;
}
return selectivity;
}