TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
IndexSearcher indexSearcher = newSearcher(indexReader);
// search for "f:a", only segments 1 and 3 should match results
Query q = new TermQuery(new Term("f", "a"));
FacetsCollector sfc = new FacetsCollector();
indexSearcher.search(q, sfc);
Facets facets = getTaxonomyFacetCounts(taxoReader, config, sfc);
FacetResult result = facets.getTopChildren(10, "A");
assertEquals("wrong number of children", 2, result.labelValues.length);
for (LabelAndValue labelValue : result.labelValues) {