lucene实现分组统计的方法_云计算

import org.apache.lucene.analysis.standard.StandardAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.document.StringField; import org.apache.lucene.facet.FacetField; import org.apache.lucene.facet.Facets; import org.apache.lucene.facet.FacetsCollector; import org.apache.lucene.facet.FacetsConfig; import org.apache.lucene.facet.LabelAndValue; import org.apache.lucene.facet.sortedset.DefaultSortedSetDocValuesReaderState; import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetCounts; import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField; import org.apache.lucene.facet.sortedset.SortedSetDocValuesReaderState; import org.apache.lucene.facet.taxonomy.TaxonomyFacetSumValueSource; import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyReader; import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyWriter; import org.apache.lucene.facet.taxonomy.directory.NRTCachingDirectoryTaxonomyWriter; import org.apache.lucene.facet.taxonomy.directory.OrdinalPolicy; import org.apache.lucene.facet.taxonomy.directory.OrdinalPolicy.Indexer; import org.apache.lucene.index.IndexWriter; import org.apache.lucene.index.IndexWriterConfig; import org.apache.lucene.index.Term; import org.apache.lucene.index.IndexWriterConfig.OpenMode; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.MatchAllDocsQuery; import org.apache.lucene.search.Query; import org.apache.lucene.search.Sort; import org.apache.lucene.search.SortField; import org.apache.lucene.search.TopDocs; import org.apache.lucene.store.Directory; import org.apache.lucene.store.FSDirectory; import org.apache.lucene.util.BytesRef; import java.io.IOException; import java.nio.file.Paths; import java.util.HashMap; import java.util.Map; public class LuceneGroupByDemo { public static void main(String[] args) throws IOException { // 创建索引和分类目录 Directory indexDir = FSDirectory.open(Paths.get("index")); Directory taxoDir = FSDirectory.open(Paths.get("taxonomy")); // 配置索引和分类写入器 IndexWriterConfig indexWriterConfig = new IndexWriterConfig(new StandardAnalyzer()); indexWriterConfig.setOpenMode(OpenMode.CREATE_OR_APPEND); IndexWriter indexWriter = new IndexWriter(indexDir, indexWriterConfig); DirectoryTaxonomyWriter taxoWriter = new NRTCachingDirectoryTaxonomyWriter(taxoDir); // 创建分类索引 OrdinalPolicy ordinalPolicy = new OrdinalPolicy.DirectPolicy(); SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexWriter.getReader(), ordinalPolicy); SortedSetDocValuesFacetField field = new SortedSetDocValuesFacetField("category", "Books", "Children's"); indexWriter.addDocument(state.facetDocValuesField(field)); field = new SortedSetDocValuesFacetField("category", "Books", "Fiction"); indexWriter.addDocument(state.facetDocValuesField(field)); field = new SortedSetDocValuesFacetField("category", "Books", "Non-fiction"); indexWriter.addDocument(state.facetDocValuesField(field)); indexWriter.commit(); // 创建分类读取器和FacetsConfig DirectoryTaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoWriter); FacetsConfig config = new FacetsConfig(); // 创建FacetsCollector和Facets FacetsCollector facetsCollector = new FacetsCollector(); IndexSearcher searcher = new IndexSearcher(indexWriter.getReader()); // 执行查询 Query query = new MatchAllDocsQuery(); searcher.search(query, facetsCollector); Facets facets = new SortedSetDocValuesFacetCounts(state, facetsCollector); // 获取分组统计结果 String[] categories = {"Books"}; Map<String, Integer> categoryCounts = new HashMap<>(); for (String category : categories) { FacetResult facetResult = facets.getTopChildren(10, category); for (LabelAndValue labelAndValue : facetResult.labelValues) { categoryCounts.put(labelAndValue.label, (int) labelAndValue.value); } } // 打印分组统计结果 for (Map.Entry<String, Integer> entry : categoryCounts.entrySet()) { System.out.println(entry.getKey() + ": " + entry.getValue()); } // 关闭资源 indexWriter.close(); taxoWriter.close(); taxo