Lucene 索引机制

package lucene.index;            

import java.io.File;            

import java.io.FileReader;            

import java.io.Reader;            

import java.util.Date;            

import org.apache.lucene.analysis.Analyzer;            

import org.apache.lucene.analysis.standard.StandardAnalyzer;            

import org.apache.lucene.document.Document;            

import org.apache.lucene.document.Field;           

import org.apache.lucene.index.IndexWriter;            

/**          

* This class demonstrates the process of creating an index with Lucene            

* for text files in a directory.            

*/            

public class TextFileIndexer {            

public static void main(String[] args) throws Exception{            

//fileDir is the directory that contains the text files to be indexed            

File   fileDir  = new File("C:\\files_to_index ");            

//indexDir is the directory that hosts Lucene's index files            

File   indexDir = new File("C:\\luceneIndex");            

Analyzer luceneAnalyzer = new StandardAnalyzer();            

IndexWriter indexWriter = new IndexWriter(indexDir,luceneAnalyzer,true);   

File[] textFiles  = fileDir.listFiles();            

long startTime = new Date().getTime();            

//Add documents to the index            

for(int i = 0; i < textFiles.length; i++){            

if(textFiles[i].isFile() >> textFiles[i].getName().endsWith(".txt")){            

System.out.println("File " + textFiles[i].getCanonicalPath()+ " is being indexed"); 

Reader textReader = new FileReader(textFiles[i]);            

Document document = new Document();            

document.add(Field.Text("content",textReader));            

document.add(Field.Text("path",textFiles[i].getPath()));            

indexWriter.addDocument(document);            

}            

}            

indexWriter.optimize(); 

indexWriter.close();            

long endTime = new Date().getTime();            

System.out.println("It took " + (endTime - startTime) + " milliseconds to create an index for the files in the directory "            + fileDir.getPath()); 

} 

}            

Analyzer luceneAnalyzer = new StandardAnalyzer();            

IndexWriter indexWriter = new IndexWriter(indexDir,luceneAnalyzer,true);