就像每个程序都有一个Hello World来让人体验它一样，lucene也可以很简单的提供一个实例。如下（来自lucene in action的例子）有两个类组成： 一个是建立索引
import java.io.File;

import java.io.FileReader;

import java.io.IOException;

import java.util.Date;

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;

public class Indexer {

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

if (args.length != 2) {

throw new Exception("Usage: java " + Indexer.class.getName() + " ");

}

File indexDir = new File(args[0]);

File dataDir = new File(args[1]);

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

int numIndexed = index(indexDir, dataDir);

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

System.out.println("Indexing " + numIndexed + " files took " + (end - start) + " milliseconds");

}

// open an index and start file directory traversal

public static int index(File indexDir, File dataDir) throws IOException {

if (!dataDir.exists() || !dataDir.isDirectory()) {

throw new IOException(dataDir + " does not exist or is not a directory");

}

IndexWriter writer = new IndexWriter(indexDir, new StandardAnalyzer(), true);

writer.setUseCompoundFile(false);

indexDirectory(writer, dataDir);

int numIndexed = writer.docCount();

writer.optimize();

writer.close();

return numIndexed;

}

// recursive method that calls itself when it finds a directory