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Lucene排序

在本章中,我們將研究的排序順序默認情況下,在給出的Lucene搜索結果或可根據需要進行操作。

按相關性排序

這是使用Lucene的默認排序方式。 Lucene通過在頂部的最相關的命中提供的結果。

private void sortUsingRelevance(String searchQuery)
   throws IOException, ParseException{
   searcher = new Searcher(indexDir);
   long startTime = System.currentTimeMillis();
   //create a term to search file name
   Term term = new Term(LuceneConstants.FILE_NAME, searchQuery);
   //create the term query object
   Query query = new FuzzyQuery(term);
   searcher.setDefaultFieldSortScoring(true, false);
   //do the search
   TopDocs hits = searcher.search(query,Sort.RELEVANCE);
   long endTime = System.currentTimeMillis();

   System.out.println(hits.totalHits +
      " documents found. Time :" + (endTime - startTime) + "ms");
   for(ScoreDoc scoreDoc : hits.scoreDocs) {
      Document doc = searcher.getDocument(scoreDoc);
      System.out.print("Score: "+ scoreDoc.score + " ");
      System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
   }
   searcher.close();
}

選擇IndexOrder排序方式

這被分揀使用lucene模式,其中索引第一文檔示出第一搜索結果中。

private void sortUsingIndex(String searchQuery)
   throws IOException, ParseException{
   searcher = new Searcher(indexDir);
   long startTime = System.currentTimeMillis();
   //create a term to search file name
   Term term = new Term(LuceneConstants.FILE_NAME, searchQuery);
   //create the term query object
   Query query = new FuzzyQuery(term);
   searcher.setDefaultFieldSortScoring(true, false);
   //do the search
   TopDocs hits = searcher.search(query,Sort.INDEXORDER);
   long endTime = System.currentTimeMillis();

   System.out.println(hits.totalHits +
      " documents found. Time :" + (endTime - startTime) + "ms");
   for(ScoreDoc scoreDoc : hits.scoreDocs) {
      Document doc = searcher.getDocument(scoreDoc);
      System.out.print("Score: "+ scoreDoc.score + " ");
      System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
   }
   searcher.close();
}

應用程序示例...

讓我們創建一個測試Lucene的應用程序來測試分選過程。

步驟 描述
1 創建下名稱為LuceneFirstApplication的一個項目作為解釋Lucene的應用在包packagecom.yiibai.lucene下,在第一個應用程序的篇章。也可以使用Lucene創建的項目理解搜索過程。
2 創建LuceneConstants.java和Searcher.java作為Lucene的解釋- 第一應用程序一章。保持其它文件不變。
3 創建LuceneTester.java如下所述。
4 清理和構建應用程序,以確保業務邏輯按要求工作。

LuceneConstants.java

這個類是用來提供可應用於示例應用程序中使用的各種常量。

package com.yiibai.lucene;

public class LuceneConstants {
   public static final String CONTENTS="contents";
   public static final String FILE_NAME="filename";
   public static final String FILE_PATH="filepath";
   public static final int MAX_SEARCH = 10;
}

Searcher.java

這個類用來讀取就使用Lucene庫的原始數據,並搜索數據的索引。

package com.yiibai.lucene;

import java.io.File;
import java.io.IOException;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.Sort;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

public class Searcher {
	
IndexSearcher indexSearcher;
   QueryParser queryParser;
   Query query;

   public Searcher(String indexDirectoryPath) throws IOException{
      Directory indexDirectory 
         = FSDirectory.open(new File(indexDirectoryPath));
      indexSearcher = new IndexSearcher(indexDirectory);
      queryParser = new QueryParser(Version.LUCENE_36,
         LuceneConstants.CONTENTS,
         new StandardAnalyzer(Version.LUCENE_36));
   }

   public TopDocs search( String searchQuery) 
      throws IOException, ParseException{
      query = queryParser.parse(searchQuery);
      return indexSearcher.search(query, LuceneConstants.MAX_SEARCH);
   }

   public TopDocs search(Query query) 
      throws IOException, ParseException{
      return indexSearcher.search(query, LuceneConstants.MAX_SEARCH);
   }

   public TopDocs search(Query query,Sort sort) 
      throws IOException, ParseException{
      return indexSearcher.search(query, 
         LuceneConstants.MAX_SEARCH,sort);
   }

   public void setDefaultFieldSortScoring(boolean doTrackScores, 
      boolean doMaxScores){
      indexSearcher.setDefaultFieldSortScoring(
         doTrackScores,doMaxScores);
   }

   public Document getDocument(ScoreDoc scoreDoc) 
      throws CorruptIndexException, IOException{
      return indexSearcher.doc(scoreDoc.doc);	
   }

   public void close() throws IOException{
      indexSearcher.close();
   }
}

LuceneTester.java

這個類是用來測試Lucene庫的搜索能力。

package com.yiibai.lucene;

import java.io.IOException;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.search.FuzzyQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.Sort;
import org.apache.lucene.search.TopDocs;

public class LuceneTester {
	
   String indexDir = "E:\Lucene\Index";
   String dataDir = "E:\Lucene\Data";
   Indexer indexer;
   Searcher searcher;

   public static void main(String[] args) {
      LuceneTester tester;
      try {
          tester = new LuceneTester();
          tester.sortUsingRelevance("cord3.txt");
          tester.sortUsingIndex("cord3.txt");
      } catch (IOException e) {
          e.printStackTrace();
      } catch (ParseException e) {
          e.printStackTrace();
      }		
   }

   private void sortUsingRelevance(String searchQuery)
      throws IOException, ParseException{
      searcher = new Searcher(indexDir);
      long startTime = System.currentTimeMillis();
      //create a term to search file name
      Term term = new Term(LuceneConstants.FILE_NAME, searchQuery);
      //create the term query object
      Query query = new FuzzyQuery(term);
      searcher.setDefaultFieldSortScoring(true, false);
      //do the search
      TopDocs hits = searcher.search(query,Sort.RELEVANCE);
      long endTime = System.currentTimeMillis();

      System.out.println(hits.totalHits +
         " documents found. Time :" + (endTime - startTime) + "ms");
      for(ScoreDoc scoreDoc : hits.scoreDocs) {
         Document doc = searcher.getDocument(scoreDoc);
         System.out.print("Score: "+ scoreDoc.score + " ");
         System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
      }
      searcher.close();
   }

   private void sortUsingIndex(String searchQuery)
      throws IOException, ParseException{
      searcher = new Searcher(indexDir);
      long startTime = System.currentTimeMillis();
      //create a term to search file name
      Term term = new Term(LuceneConstants.FILE_NAME, searchQuery);
      //create the term query object
      Query query = new FuzzyQuery(term);
      searcher.setDefaultFieldSortScoring(true, false);
      //do the search
      TopDocs hits = searcher.search(query,Sort.INDEXORDER);
      long endTime = System.currentTimeMillis();

      System.out.println(hits.totalHits +
      " documents found. Time :" + (endTime - startTime) + "ms");
      for(ScoreDoc scoreDoc : hits.scoreDocs) {
         Document doc = searcher.getDocument(scoreDoc);
         System.out.print("Score: "+ scoreDoc.score + " ");
         System.out.println("File: "+ doc.get(LuceneConstants.FILE_PATH));
      }
      searcher.close();
   }
}

數據和索引目錄的創建

從record1.txt到record10.txt的文件中包含簡單的名稱以及學生的其他細節,並把它們放在目錄E:LuceneData。這是測試數據。索引目錄路徑應創建為E:LuceneIndex。期間,運行 Lucene索引程序後- 索引過程中,可以看到該文件夾中創建的索引文件的列表。

運行程序:

一旦創建源,創造了原始數據,數據目錄,索引目錄和索引完成後,已經準備好這一步是編譯和運行程序。要做到這一點,請LuceneTester.Java文件選項卡中使用Eclipse IDE可使用Run選項,或使用Ctrl+ F11來編譯和運行應用程序LuceneTester。如果您的應用程序一切正常,這將在Eclipse IDE的控製台打印以下消息:

10 documents found. Time :31ms
Score: 1.3179655 File: E:LuceneData
ecord3.txt
Score: 0.790779 File: E:LuceneData
ecord1.txt
Score: 0.790779 File: E:LuceneData
ecord2.txt
Score: 0.790779 File: E:LuceneData
ecord4.txt
Score: 0.790779 File: E:LuceneData
ecord5.txt
Score: 0.790779 File: E:LuceneData
ecord6.txt
Score: 0.790779 File: E:LuceneData
ecord7.txt
Score: 0.790779 File: E:LuceneData
ecord8.txt
Score: 0.790779 File: E:LuceneData
ecord9.txt
Score: 0.2635932 File: E:LuceneData
ecord10.txt
10 documents found. Time :0ms
Score: 0.790779 File: E:LuceneData
ecord1.txt
Score: 0.2635932 File: E:LuceneData
ecord10.txt
Score: 0.790779 File: E:LuceneData
ecord2.txt
Score: 1.3179655 File: E:LuceneData
ecord3.txt
Score: 0.790779 File: E:LuceneData
ecord4.txt
Score: 0.790779 File: E:LuceneData
ecord5.txt
Score: 0.790779 File: E:LuceneData
ecord6.txt
Score: 0.790779 File: E:LuceneData
ecord7.txt
Score: 0.790779 File: E:LuceneData
ecord8.txt
Score: 0.790779 File: E:LuceneData
ecord9.txt