Lucene排序


在本章中,我們將研究的排序順序預設情況下,在給出的Lucene搜尋結果或可根據需要進行操作。

按相關性排序

這是使用Lucene的預設排序方式。 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,其中索引第一文件示出第一搜尋結果中。

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();
}

應用程式範例...

讓我們建立一個測試Lucene的應用程式來測試分選過程。

步驟 描述
1 建立下名稱為LuceneFirstApplication的一個專案作為解釋Lucene的應用在包packagecom.yiibai.lucene下,在第一個應用程式的篇章。也可以使用Lucene建立的專案理解搜尋過程。
2 建立LuceneConstants.java和Searcher.java作為Lucene的解釋- 第一應用程式一章。保持其它檔案不變。
3 建立LuceneTester.java如下所述。
4 清理和構建應用程式,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範例應用程式中使用的各種常數。

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庫的原始資料,並搜尋資料的索引。

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庫的搜尋能力。

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();
   }
}

資料和索引目錄的建立

從record1.txt到record10.txt的檔案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。這是測試資料。索引目錄路徑應建立為E:LuceneIndex。期間,執行 Lucene索引程式後- 索引過程中,可以看到該檔案夾中建立的索引檔案的列表。

執行程式:

一旦建立源,創造了原始資料,資料目錄,索引目錄和索引完成後,已經準備好這一步是編譯和執行程式。要做到這一點,請LuceneTester.Java檔案索引標籤中使用Eclipse IDE可使用Run選項,或使用Ctrl+ F11來編譯和執行應用程式LuceneTester。如果您的應用程式一切正常,這將在Eclipse IDE的控制台列印以下訊息:

10 documents found. Time :31ms
Score: 1.3179655 File: E:LuceneDataecord3.txt
Score: 0.790779 File: E:LuceneDataecord1.txt
Score: 0.790779 File: E:LuceneDataecord2.txt
Score: 0.790779 File: E:LuceneDataecord4.txt
Score: 0.790779 File: E:LuceneDataecord5.txt
Score: 0.790779 File: E:LuceneDataecord6.txt
Score: 0.790779 File: E:LuceneDataecord7.txt
Score: 0.790779 File: E:LuceneDataecord8.txt
Score: 0.790779 File: E:LuceneDataecord9.txt
Score: 0.2635932 File: E:LuceneDataecord10.txt
10 documents found. Time :0ms
Score: 0.790779 File: E:LuceneDataecord1.txt
Score: 0.2635932 File: E:LuceneDataecord10.txt
Score: 0.790779 File: E:LuceneDataecord2.txt
Score: 1.3179655 File: E:LuceneDataecord3.txt
Score: 0.790779 File: E:LuceneDataecord4.txt
Score: 0.790779 File: E:LuceneDataecord5.txt
Score: 0.790779 File: E:LuceneDataecord6.txt
Score: 0.790779 File: E:LuceneDataecord7.txt
Score: 0.790779 File: E:LuceneDataecord8.txt
Score: 0.790779 File: E:LuceneDataecord9.txt