taxoWriter.commit();
TaxonomyReader taxoReader = new DirectoryTaxonomyReader(dir);
assertEquals("wrong refCount", 1, taxoReader.getRefCount());
taxoReader.incRef();
assertEquals("wrong refCount", 2, taxoReader.getRefCount());
taxoWriter.addCategory(new CategoryPath("a", "b"));
taxoWriter.commit();
TaxonomyReader newtr = TaxonomyReader.openIfChanged(taxoReader);