在sql语句中,有升序和降序排列。在Lucene中,同样也有。
Sort里的属性 | SortField里的属性 | 含义 |
Sort.INDEXORDER | SortField.FIELD_DOC | 按照索引的顺序进行排序 |
Sort.RELEVANCE | SortField.FIELD_SCORE | 按照关联性评分进行排序 |
=========SortField类============ //field是排序字段type是排序类型 public SortField(String field, Type type); //field是排序字段type是排序类型reverse是指定升序还是降序 //reverse 为true是降序 false为升序 public SortField(String field, Type type, boolean reverse) =========Sort类============ public Sort();//Sort对象构造方法默认是按文档评分排序 public Sort(SortField field);//排序的一个SortField public Sort(SortField... fields)//排序的多个SortField可以传入一个数组
前提,创建索引:
1 import java.io.File; 2 import java.io.FileReader; 3 import java.io.IOException; 4 import java.nio.file.Paths; 5 import java.util.Random; 6 7 import org.apache.lucene.analysis.standard.StandardAnalyzer; 8 import org.apache.lucene.document.Document; 9 import org.apache.lucene.document.Field; 10 import org.apache.lucene.document.IntField; 11 import org.apache.lucene.document.LongField; 12 import org.apache.lucene.document.NumericDocValuesField; 13 import org.apache.lucene.index.IndexWriter; 14 import org.apache.lucene.index.IndexWriterConfig; 15 import org.apache.lucene.store.Directory; 16 import org.apache.lucene.store.FSDirectory; 17 18 public class FileIndexUtils { 19 private static Directory directory = null; 20 static{ 21 try { 22 directory = FSDirectory.open(Paths.get("D://lucene//document")); 23 } catch (Exception e) { 24 // TODO: handle exception 25 e.printStackTrace(); 26 } 27 } 28 public static Directory getDirectory(){ 29 return directory; 30 } 31 /** 32 * 创建索引 33 * @param hasNew 34 */ 35 @SuppressWarnings("deprecation") 36 public static void createIndex(boolean hasNew){ 37 IndexWriter writer = null; 38 try { 39 writer = new IndexWriter(directory, new IndexWriterConfig(new StandardAnalyzer())); 40 if(hasNew){ 41 writer.deleteAll(); 42 } 43 44 Document document = null; 45 int index = 0; 46 //随机数,为排序数字 47 Random random = new Random(); 48 //为源文件创建索引 49 File file = new File("D://text"); 50 for(File f:file.listFiles()){ 51 int score = random.nextInt(); 52 document = new Document(); 53 document.add(new Field("id",String.valueOf(index++), Field.Store.YES,Field.Index.NOT_ANALYZED_NO_NORMS)); 54 document.add(new Field("content",new FileReader(f))); 55 document.add(new Field("fileName",f.getName(),Field.Store.YES,Field.Index.NOT_ANALYZED)); 56 document.add(new Field("path",f.getPath(),Field.Store.YES,Field.Index.NOT_ANALYZED)); 57 document.add(new IntField("score",score,Field.Store.YES)); 58 document.add(new NumericDocValuesField("size",(long)f.length())); 59 document.add(new LongField("size", f.length(), Field.Store.YES)); 60 document.add(new IntField("date",(int) f.lastModified(),Field.Store.YES)); 61 writer.addDocument(document); 62 } 63 } catch (Exception e) { 64 // TODO: handle exception 65 e.printStackTrace(); 66 }finally{ 67 if(writer!=null){ 68 try { 69 writer.close(); 70 } catch (IOException e) { 71 // TODO Auto-generated catch block 72 e.printStackTrace(); 73 } 74 } 75 } 76 } 77 }
一,Sort排序
getSearcher()
1 private static IndexReader reader = null; 2 static{ 3 try { 4 reader = DirectoryReader.open(FileIndexUtils.getDirectory()); 5 } catch (Exception e) { 6 // TODO: handle exception 7 e.printStackTrace(); 8 } 9 } 10 11 public IndexSearcher getSearcher(){ 12 try { 13 if(reader == null){ 14 reader = DirectoryReader.open(FileIndexUtils.getDirectory()); 15 }else{ 16 IndexReader tr = DirectoryReader.openIfChanged((DirectoryReader) reader); 17 if(tr!=null) { 18 reader.close(); 19 reader = tr; 20 } 21 } 22 return new IndexSearcher(reader); 23 } catch (Exception e) { 24 // TODO: handle exception 25 e.printStackTrace(); 26 } 27 return null; 28 }
/** * 排序Sort * @param queryStr * @param sort */ public void searcherBySort(String queryStr,Sort sort) { try { IndexSearcher searcher = getSearcher(); QueryParser parser = new QueryParser("content",new StandardAnalyzer()); Query query = parser.parse(queryStr); TopDocs tds = null; if(sort!=null) tds = searcher.search(query, 50, sort); else { tds = searcher.search(query, 50); } for(ScoreDoc sd:tds.scoreDocs) { Document d = searcher.doc(sd.doc); System.out.println(sd.doc+":("+sd.score+")" + "["+d.get("fileName")+"【"+d.get("path")+"】---"+d.get("score")+"--->"+ Integer.valueOf(d.get("size"))/1024+"-----"); } } catch (Exception e) { e.printStackTrace(); } }
测试:
@Test public void test01(){ st.searcherBySort("select",Sort.RELEVANCE); System.out.println("------------"); st.searcherBySort("select",null); }
二、SortField
/** * 排序SortField * @param sortField * @param reverse */ public void searcherBySortField(String filename,boolean reverse){ try { IndexSearcher searcher = getSearcher(); SortField sortField = new SortField(filename,SortField.Type.LONG,reverse); Sort sort = new Sort(sortField); TopDocs tds = searcher.search(new MatchAllDocsQuery(),100,sort); for(ScoreDoc sd:tds.scoreDocs){ Document d = searcher.doc(sd.doc); System.out.println("["+d.get("fileName")+"]【"+d.get("path")+"】---score:"+d.get("score")+"--->"+"size:"+d.get("size")); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); }finally{ try { if(reader!=null){ reader.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
测试:
@Test public void test02(){ st.searcherBySortField("size", false); System.out.println("------------"); }
size根据大小排序。