Lucene4.3入门

      辞职交接期间无聊看了一下搜索引擎，java社区比较火的当然是Lucene,想写一个简单的小例子，在网上找了些资料，不过都不是4.3的，自己看了一下。

下载地址：http://lucene.apache.org/core/

项目结构

constans.java 是常量类

LuceneIndex.java 建立索引类

LuceneSearch.java 搜索类

数据文件：

      package com.xin;
      public class Constants {
      public final static String INDEX_FILE_PATH = "e:\\lucene\\test"; //索引的文件的存放路径 
      public final static String INDEX_STORE_PATH = "e:\\lucene\\index"; //索引的存放位置 
      }
  
 

      package com.xin;
      import java.io.BufferedReader;
      import java.io.File;
      import java.io.FileInputStream;
      import java.io.InputStreamReader;
      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.document.StringField;
      import org.apache.lucene.document.TextField;
      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;
      /**
       * @author chongxin
       * @since 2013/6/19
       * @version Lucene 4.3.1
       * */
      public class LuceneIndex {
     	// 索引器
     	private IndexWriter writer = null;
     	public LuceneIndex() {
     		try {
     			//索引文件的保存位置
      			Directory dir = FSDirectory.open(new File(Constants.INDEX_STORE_PATH));
     			//分析器
      			Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_40);
     			//配置类
      			IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_40,analyzer);
      			iwc.setOpenMode(OpenMode.CREATE);//创建模式 OpenMode.CREATE_OR_APPEND 添加模式
      			writer = new IndexWriter(dir, iwc);
      		} catch (Exception e) {
      			e.printStackTrace();
      		}
      	}
     	// 将要建立索引的文件构造成一个Document对象，并添加一个域"content"
     	private Document getDocument(File f) throws Exception {
      		Document doc = new Document();
      		FileInputStream is = new FileInputStream(f);
      		Reader reader = new BufferedReader(new InputStreamReader(is));
     		//字符串 StringField LongField TextField
      		Field pathField = new StringField("path", f.getAbsolutePath(),Field.Store.YES);
      		Field contenField = new TextField("contents", reader);
     		//添加字段
      		doc.add(contenField);
      		doc.add(pathField);
     		return doc;
      	}
     	public void writeToIndex() throws Exception {
      		File folder = new File(Constants.INDEX_FILE_PATH);
     		if (folder.isDirectory()) {
      			String[] files = folder.list();
     			for (int i = 0; i < files.length; i++) {
       File file = new File(folder, files[i]);
       Document doc = getDocument(file);
       System.out.println("正在建立索引 : " + file + "");
       writer.addDocument(doc);
      			}
      		}
      	}
     	public void close() throws Exception {
      		writer.close();
      	}
     	public static void main(String[] args) throws Exception {
     		// 声明一个对象
      		LuceneIndex indexer = new LuceneIndex();
     		// 建立索引
      		Date start = new Date();
      		indexer.writeToIndex();
      		Date end = new Date();
      		System.out.println("建立索引用时" + (end.getTime() - start.getTime()) + "毫秒");
      		indexer.close();
      	}
      }
  
 

      正在建立索引 : e:\lucene\test\a.txt
      正在建立索引 : e:\lucene\test\b.txt
      正在建立索引 : e:\lucene\test\c.txt
      正在建立索引 : e:\lucene\test\d.txt
      建立索引用时109毫秒
  
 

生成的索引文件：

查找：

      package com.xin;
      import java.io.File;
      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.index.DirectoryReader;
      import org.apache.lucene.index.IndexReader;
      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.search.TopDocs;
      import org.apache.lucene.store.FSDirectory;
      import org.apache.lucene.util.Version;
      /**
       * @author chongxin
       * @since 2013/6/19
       * @version Lucene 4.3.1
       * */
      public class LuceneSearch {
     	// 声明一个IndexSearcher对象
     	private IndexSearcher searcher = null;
     	// 声明一个Query对象
     	private Query query = null;
     	private String field = "contents";
     	public LuceneSearch() {
     		try {
      			IndexReader reader = DirectoryReader.open(FSDirectory.open(new File(Constants.INDEX_STORE_PATH)));
      			searcher = new IndexSearcher(reader);
      		} catch (Exception e) {
      			e.printStackTrace();
      		}
      	}
      //返回查询结果 
     	public final TopDocs search(String keyword) {
      		System.out.println("正在检索关键字 : " + keyword);
     		try {
      			Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_40);
      			QueryParser parser = new QueryParser(Version.LUCENE_40, field,analyzer);
     			// 将关键字包装成Query对象
      			query = parser.parse(keyword);
      			Date start = new Date();
      			TopDocs results = searcher.search(query, 5 * 2);
      			Date end = new Date();
      			System.out.println("检索完成，用时" + (end.getTime() - start.getTime())
       + "毫秒");
     			return results;
      		} catch (Exception e) {
      			e.printStackTrace();
     			return null;
      		}
      	}
      //打印结果
     	public void printResult(TopDocs results) {
      		ScoreDoc[] h = results.scoreDocs;
     		if (h.length == 0) {
      			System.out.println("对不起，没有找到您要的结果。");
      		} else {
     			for (int i = 0; i < h.length; i++) {
      try {
       Document doc = searcher.doc(h[i].doc);
       System.out.print("这是第" + i + "个检索到的结果，文件名为：");
       System.out.println(doc.get("path"));
       } catch (Exception e) {
       e.printStackTrace();
       }
      			}
      		}
      		System.out.println("--------------------------");
      	}
     	public static void main(String[] args) throws Exception {
      		LuceneSearch test = new LuceneSearch();
      		TopDocs h = null;
      		h = test.search("中国");
      		test.printResult(h);
      		h = test.search("人民");
      		test.printResult(h);
      		h = test.search("共和国");
      		test.printResult(h);
      	}
      }
  
 

文章来源: gamwatcher.blog.csdn.net，作者：香菜聊游戏，版权归原作者所有，如需转载，请联系作者。

原文链接：gamwatcher.blog.csdn.net/article/details/9128323