Lucene官方一个简单的实例

Lucene 是一个基于 Java 的全文信息检索工具包，它不是一个完整的搜索应用程序，而是为你的应用程序提供索引和搜索功能。Lucene 目前是 Apache家族中的一个开源项目。也是目前最为流行的基于 Java 开源全文检索工具包。

官方简单的例子：版本(lucene 4.1.0)

导入lucene-core-4.1.0.jar、lucene-analyzers-common-4.1.0.jar、lucene-queries-4.1.0.jar、lucene-queryparser-4.1.0.jar

1.IndexWriter建立索引的类；

2.IndexSearcher搜索索引的类

package com.mei.testlucene;

import java.io.File;
import java.io.IOException;
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.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.queryparser.classic.ParseException;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;

public class HelloLucene {
  public static void main(String[] args) throws IOException, ParseException {
		Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_CURRENT);
		 // Store the index in memory:
	    Directory directory = new RAMDirectory();
	    // To store an index on disk, use this instead:
	    //Directory directory = FSDirectory.open(new File("H:/luceneIndex"));
	    IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_CURRENT, analyzer);
	    IndexWriter iwriter = new IndexWriter(directory, config);
	    Document doc = new Document();
	    String text = "This is the text to be indexed.";
	    doc.add(new Field("fieldname", text, TextField.TYPE_STORED));
	    iwriter.addDocument(doc);
	    iwriter.close();
	    System.out.println("建立索引 ok");
	    
	    // Now search the index:
	    DirectoryReader ireader = DirectoryReader.open(directory);
	    IndexSearcher isearcher = new IndexSearcher(ireader);
	    // Parse a simple query that searches for "text":
	    QueryParser parser = new QueryParser(Version.LUCENE_CURRENT, "fieldname", analyzer);
	    Query query = parser.parse("text");
	    ScoreDoc[] hits = isearcher.search(query, null, 1000).scoreDocs;
	    System.out.println(hits.length == 1);
	    // Iterate through the results:
	    for (int i = 0; i < hits.length; i++) {
	      Document hitDoc = isearcher.doc(hits[i].doc);
	      System.out.println(hitDoc.get("fieldname"));
	    }
	    ireader.close();
	    directory.close();
	}
}