关于lucene搜索时排序的问题

       在Lucene4.6中，想要实现搜索结果按照时间倒序的效果：如果两个文档得分相同，那么就按照发布时间倒序排列；否则就按照分数排列。这种效果在 Lucene4.6中实现起来极其简单，直接利用search接口的Sort参数即可达成，完全不需要像某些人说的重写Similarity那么麻烦。三 两行代码的事情，体现了Make it simple, stupid的精髓。

package com.hankcs.test; 
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.document.*;
import org.apache.lucene.index.*;
import org.apache.lucene.queries.CustomScoreQuery;
import org.apache.lucene.queries.function.FunctionQuery;
import org.apache.lucene.queryparser.classic.ParseException;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.*;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.LockObtainFailedException;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;import org.wltea.analyzer.lucene.IKAnalyzer; 
import java.io.IOException; 
/** * @author hankcs */
public class TestSortByTime{  
  public static void main(String[] args)    {   
       // Lucene Document的主要域名       
        String fieldName = "text";      
           // 实例化IKAnalyzer分词器       
            Analyzer analyzer = new IKAnalyzer();       
              Directory directory = null;        
              IndexWriter iwriter;        
              IndexReader ireader = null;        
              IndexSearcher isearcher;        
              try        {            
              //索引过程**********************************           
               //建立内存索引对象            
               directory = new RAMDirectory();             
               //配置IndexWriterConfig            
               IndexWriterConfig iwConfig = new IndexWriterConfig(Version.LUCENE_46, analyzer);  
               iwConfig.setOpenMode(IndexWriterConfig.OpenMode.CREATE_OR_APPEND);         
                  iwriter = new IndexWriter(directory, iwConfig);            
                  //写入索引            
                  for (int i = 0; i < 3; ++i) {                
                  int year = 2004 + i;                
                  Document doc = new Document();                
                  doc.add(new TextField(fieldName, year + "全民突击攻略", Field.Store.YES));
                  doc.add(new IntField("date",  year * 10000 + 1111, Field.Store.YES));             
                  iwriter.addDocument(doc);}            
                  // 加入一个干扰文档            
                  Document doc = new Document();            
                  doc.add(new TextField(fieldName, "天天酷跑攻略", Field.Store.YES));            
                  doc.add(new IntField("date",  20141111, Field.Store.YES));            
                  iwriter.addDocument(doc);            
                  iwriter.close();             
                  //搜索过程**********************************            
                  //实例化搜索器            
                  ireader = DirectoryReader.open(directory);            
                  isearcher = new IndexSearcher(ireader);             
                  String keyword = "全民突击攻略";            
                  //使用QueryParser查询分析器构造Query对象            
                  QueryParser qp = new QueryParser(Version.LUCENE_46, fieldName, analyzer);         
                  Query query = qp.parse(keyword);            
                  System.out.println("Query = " + query);             
                  //搜索相似度最高的5条记录            
                  Sort sort = new Sort(new SortField("text", SortField.Type.SCORE), new SortField("date", SortField.Type.INT, true));            To
                  pDocs topDocs = isearcher.search(query, 5, sort);            
                  System.out.println("命中：" + topDocs.totalHits);           
                   //输出结果            
                   ScoreDoc[] scoreDocs = topDocs.scoreDocs;            
                   for (int i = 0; i < Math.min(5, scoreDocs.length); i++){                
                   Document targetDoc = isearcher.doc(scoreDocs[i].doc);                
                   System.out.print(targetDoc.getField(fieldName).stringValue());                
                   System.out.print(" , " + targetDoc.getField("date").numericValue());                
                   System.out.println(" , " + scoreDocs[i].score);            }        
                    } catch (CorruptIndexException e)        {           
                     e.printStackTrace();        
                     } catch (LockObtainFailedException e)        {            
                     e.printStackTrace();        
                     } catch (IOException e){            
                     e.printStackTrace();        
                     } catch (ParseException e)        {            
                     e.printStackTrace();        
                     } finally        {           
                      if (ireader != null)  {
                      try{                    
                      ireader.close();                
                      } catch (IOException e)                { 
                    e.printStackTrace();                } 
                               }           
                                if (directory != null)            {    
                                            try                {       
                                                         directory.close();             
                                                            } catch (IOException e)                {
                                                                                e.printStackTrace();                }    
                                                                                        }        }    }}