学步园

Apache Lucene是一个开放源程序的搜寻器引擎，利用它可以轻易地为Java软件加入全文搜寻功能。Lucene的最主要工作是替文件的每一个字作索引，索引让搜寻的效率比传统的逐字比较大大提高，Lucen提供一组解读，过滤，分析文件，编排和使用索引的API，它的强大之处除了高效和简单外，是最重要的是使使用者可以随时应自己需要自订其功能。

首先在自己的电脑上建三个文本供建立索引使用，我一共建了三个文本

然后编写一个索引类：

package com.lucene.test;

import java.io.BufferedReader; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.InputStreamReader; 

import org.apache.lucene.analysis.Analyzer; 
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.document.Document; 
import org.apache.lucene.document.Field; 
import org.apache.lucene.index.IndexWriter; 
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.store.Directory; 
import org.apache.lucene.store.FSDirectory; 
import org.apache.lucene.util.Version;

public class TestFileIndex { 
  public static void main(String[] args) throws Exception { 
    String dataDir="d:/lucene/data"; 
    String indexDir="d:/lucene/index"; 
     
    File[] files=new File(dataDir).listFiles(); 
     
    Analyzer analyzer=new SmartChineseAnalyzer(Version.LUCENE_36, true);
    Directory dir=FSDirectory.open(new File(indexDir)); 
    
    IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_36, analyzer);
	iwc.setOpenMode(OpenMode.CREATE_OR_APPEND);
	IndexWriter writer = new IndexWriter(dir, iwc); 
     
    for(int i=0;i<files.length;i++){
      System.out.println("文件： "+files[i].getName()+"  索引建立中....");
      Long startTime = System.currentTimeMillis();
      StringBuffer strBuffer=new StringBuffer(); 
      String line=""; 
      FileInputStream is=new FileInputStream(files[i].getCanonicalPath()); 
      BufferedReader reader=new BufferedReader(new InputStreamReader(is,"gb2312")); 
      line=reader.readLine(); 
      while(line != null){ 
        strBuffer.append(line); 
        strBuffer.append("\n"); 
        line=reader.readLine(); 
      } 
        
      Document doc=new Document(); 
      doc.add(new Field("fileName", files[i].getName(), Field.Store.YES, Field.Index.ANALYZED)); 
      doc.add(new Field("contents", strBuffer.toString(), Field.Store.YES, Field.Index.ANALYZED)); 
      writer.addDocument(doc); 
      reader.close(); 
      is.close(); 
      Long endTime = System.currentTimeMillis();
      System.out.println("文件： "+files[i].getName()+"索引建立结束。      所用时间为："+(endTime - startTime)+"毫秒"  );
    } 
     
    writer.commit();
    writer.close(); 
    dir.close(); 
    System.out.println("索引结束"); 
  } 
} 

运行完，在index文件夹下回产生索引文件：

再编写一个searcher类，检索index文件夹，作为测试：

package com.lucene.test;

import java.io.File; 


import org.apache.lucene.analysis.Analyzer; 
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.document.Document; 
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
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.TermQuery;
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 TestFileSearcher { 
  public static void main(String[] args) throws Exception { 
    String indexDir = "d:/lucene/index"; 
    Analyzer analyzer = new SmartChineseAnalyzer(Version.LUCENE_36, true);
    Directory dir = FSDirectory.open(new File(indexDir)); 
    
    IndexReader reader;
	reader = IndexReader.open(FSDirectory.open(new File(indexDir)));
	IndexSearcher searcher = new IndexSearcher(reader);
    
    QueryParser parser = new QueryParser(Version.LUCENE_36, "contents",analyzer); 
    Query query = parser.parse("青元"); 
   
   // Term term=new Term("fileName", "test"); 
   // TermQuery query=new TermQuery(term); 
     
    TopDocs docs=searcher.search(query, 1000); 
    ScoreDoc[] hits=docs.scoreDocs; 
    System.out.println(hits.length); 
    for(int i=0;i<hits.length;i++){ 
      Document doc=searcher.doc(hits[i].doc); 
      System.out.print(doc.get("fileName")+"\n"); 
     // System.out.println(doc.get("contents")+"\n"); 
    } 
     
    searcher.close(); 
    dir.close(); 
  } 
}