Lucene入门及实际项目应用场景

导入maven依赖


<dependency>
    <groupId>org.apache.lucene</groupId>
    <artifactId>lucene-core</artifactId>
    <version>5.3.1</version>
</dependency>
<dependency>
    <groupId>org.apache.lucene</groupId>
    <artifactId>lucene-queryparser</artifactId>
    <version>5.3.1</version>
</dependency>
<dependency>
    <groupId>org.apache.lucene</groupId>
    <artifactId>lucene-analyzers-common</artifactId>
    <version>5.3.1</version>
</dependency>

Helloword实现

生成索引

目的：索引数据目录，在指定目录生成索引文件

1、构造方法实例化IndexWriter

　　获取索引文件存放地址对象

　　获取输出流

　　设置输出流的对应配置

　　给输出流配置设置分词器

2、关闭索引输出流

3、索引指定路径下的所有文件

4、索引指定的文件

5、获取文档（索引文件中包含的重要信息，key-value的形式）

6、测试

package com.liuwenwu.lucene;

import java.io.File;
import java.io.FileReader;
import java.nio.file.Paths;

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.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.FSDirectory;

/**
 * 配合Demo1.java进行lucene的helloword实现
 * @author Administrator
 *
 */
public class IndexCreate {
    private IndexWriter indexWriter;
    
    /**
     * 1、构造方法 实例化IndexWriter
     * @param indexDir
     * @throws Exception
     */
    public IndexCreate(String indexDir) throws Exception{
//        获取索引文件的存放地址对象
        FSDirectory dir = FSDirectory.open(Paths.get(indexDir));
//        标准分词器（针对英文）
        Analyzer analyzer = new StandardAnalyzer();
//        索引输出流配置对象
        IndexWriterConfig conf = new IndexWriterConfig(analyzer); 
        indexWriter = new IndexWriter(dir, conf);
    }
    
    /**
     * 2、关闭索引输出流
     * @throws Exception
     */
    public void closeIndexWriter()  throws Exception{
        indexWriter.close();
    }
    
    /**
     * 3、索引指定路径下的所有文件
     * @param dataDir
     * @return
     * @throws Exception
     */
    public int index(String dataDir) throws Exception{
        File[] files = new File(dataDir).listFiles();
        for (File file : files) {
            indexFile(file);
        }
        return indexWriter.numDocs();
    }
    
    /**
     * 4、索引指定的文件
     * @param file
     * @throws Exception
     */
    private void indexFile(File file) throws Exception{
        System.out.println("被索引文件的全路径："+file.getCanonicalPath());
        Document doc = getDocument(file);
        indexWriter.addDocument(doc);
    }
    
    /**
     * 5、获取文档（索引文件中包含的重要信息，key-value的形式）
     * @param file
     * @return
     * @throws Exception
     */
    private Document getDocument(File file) throws Exception{
        Document doc = new Document();
        doc.add(new TextField("contents", new FileReader(file)));
//        Field.Store.YES是否存储到硬盘
        doc.add(new TextField("fullPath", file.getCanonicalPath(),Field.Store.YES));
        doc.add(new TextField("fileName", file.getName(),Field.Store.YES));
        return doc;
    }
}

package com.liuwenwu.lucene;

/**
 * 生成索引测试
 * @author Administrator
 *
 */
public class Demo1 {
    public static void main(String[] args) {
//        索引文件将要存放的位置
        String indexDir = "F:\\y2\\lucene\\demo1";
//        数据源地址
        String dataDir = "F:\\y2\\lucene\\demo1\\data";
        IndexCreate ic = null; 
        try {
            ic = new IndexCreate(indexDir);
            long start = System.currentTimeMillis();
            int num = ic.index(dataDir);
            long end = System.currentTimeMillis();
            System.out.println("检索指定路径下"+num+"个文件，一共花费了"+(end-start)+"毫秒");
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            try {
                ic.closeIndexWriter();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

使用索引

从索引文件中拿数据

1、获取输入流（通过dirReader）

2、获取索引搜索对象（通过输入流来拿）

3、获取查询对象（通过查询解析器来获取，解析器是通过分词器获取）

4、获取包含关键字排前面的文档对象集合

5、可以获取对应文档的内容

package com.liuwenwu.lucene;

import java.nio.file.Paths;

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;

/**
 * 配合Demo2.java进行lucene的helloword实现
 * @author Administrator
 *
 */
public class IndexUse {
    /**
     * 通过关键字在索引目录中查询
     * @param indexDir    索引文件所在目录
     * @param q    关键字
     */
    public static void search(String indexDir, String q) throws Exception{
        FSDirectory indexDirectory = FSDirectory.open(Paths.get(indexDir));
//        注意:索引输入流不是new出来的，是通过目录读取工具类打开的
        IndexReader indexReader = DirectoryReader.open(indexDirectory);
//        获取索引搜索对象
        IndexSearcher indexSearcher = new IndexSearcher(indexReader);
        Analyzer analyzer = new StandardAnalyzer();
//        查询解析器
        QueryParser queryParser = new QueryParser("contents", analyzer);
//        获取符合关键字的查询对象
        Query query = queryParser.parse(q);
        
        long start=System.currentTimeMillis();
//        获取关键字出现的前十次
        TopDocs topDocs = indexSearcher.search(query , 10);
        long end=System.currentTimeMillis();
        System.out.println("匹配 "+q+" ，总共花费"+(end-start)+"毫秒"+"查询到"+topDocs.totalHits+"个记录");
        
        for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
            int docID = scoreDoc.doc;
//            索引搜索对象通过文档下标获取文档
            Document doc = indexSearcher.doc(docID);
            System.out.println("通过索引文件："+doc.get("fullPath")+"拿数据");
        }
        
        indexReader.close();
    }
}

package com.liuwenwu.lucene;

/**
 * 查询索引测试
 * @author Administrator
 *
 */
public class Demo2 {
    public static void main(String[] args) {
//        索引文件地址
        String indexDir = "F:\\y2\\lucene\\demo1";
//        搜索条件
        String q = "EarlyTerminating-Collector";
        try {
            IndexUse.search(indexDir, q);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

结果：

构建索引

package com.liuwenwu.lucene;

import java.nio.file.Paths;

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.Term;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;

/**
 * 构建索引
 *     对索引的增删改
 * @author Administrator
 *
 */
public class Demo3 {
    private String ids[]={"1","2","3"};
    private String citys[]={"qingdao","nanjing","shanghai"};
    private String descs[]={
            "Qingdao is a beautiful city.",
            "Nanjing is a city of culture.",
            "Shanghai is a bustling city."
    };
    private FSDirectory dir;
    
    /**
     * 每次都生成索引文件
     * @throws Exception
     */
    @Before
    public void setUp() throws Exception {
        dir  = FSDirectory.open(Paths.get("F:\\y2\\lucene\\demo2\\indexDir"));
        IndexWriter indexWriter = getIndexWriter();
        for (int i = 0; i < ids.length; i++) {
            Document doc = new Document();
            doc.add(new StringField("id", ids[i], Field.Store.YES));
            doc.add(new StringField("city", citys[i], Field.Store.YES));
            doc.add(new TextField("desc", descs[i], Field.Store.NO));
            indexWriter.addDocument(doc);
        }
        indexWriter.close();
    }

    /**
     * 获取索引输出流
     * @return
     * @throws Exception
     */
    private IndexWriter getIndexWriter()  throws Exception{
        Analyzer analyzer = new StandardAnalyzer();
        IndexWriterConfig conf = new IndexWriterConfig(analyzer);
        return new IndexWriter(dir, conf );
    }
    
    /**
     * 测试写了几个索引文件
     * @throws Exception
     */
    @Test
    public void getWriteDocNum() throws Exception {
        IndexWriter indexWriter = getIndexWriter();
        System.out.println("索引目录下生成"+indexWriter.numDocs()+"个索引文件");
    }
    
    /**
     * 打上标记，该索引实际并未删除
     * @throws Exception
     */
    @Test
    public void deleteDocBeforeMerge() throws Exception {
        IndexWriter indexWriter = getIndexWriter();
        System.out.println("最大文档数："+indexWriter.maxDoc());
        indexWriter.deleteDocuments(new Term("id", "1"));
        indexWriter.commit();
        
        System.out.println("最大文档数："+indexWriter.maxDoc());
        System.out.println("实际文档数："+indexWriter.numDocs());
        indexWriter.close();
    }
    
    /**
     * 对应索引文件已经删除,但是该版本的分词会保留
     * @throws Exception
     */
    @Test
    public void deleteDocAfterMerge() throws Exception {
//        https://blog.csdn.net/asdfsadfasdfsa/article/details/78820030
//        org.apache.lucene.store.LockObtainFailedException: Lock held by this virtual machine:indexWriter是单例的、线程安全的，不允许打开多个。
        IndexWriter indexWriter = getIndexWriter();
        System.out.println("最大文档数："+indexWriter.maxDoc());
        indexWriter.deleteDocuments(new Term("id", "1"));
        indexWriter.forceMergeDeletes(); //强制删除
        indexWriter.commit();
        
        System.out.println("最大文档数："+indexWriter.maxDoc());
        System.out.println("实际文档数："+indexWriter.numDocs());
        indexWriter.close();
    }
    
    /**
     * 测试更新索引
     * @throws Exception
     */
    @Test
    public void testUpdate()throws Exception{
        IndexWriter writer=getIndexWriter();
        Document doc=new Document();
        doc.add(new StringField("id", "1", Field.Store.YES));
        doc.add(new StringField("city","qingdao",Field.Store.YES));
        doc.add(new TextField("desc", "dsss is a city.", Field.Store.NO));
        writer.updateDocument(new Term("id","1"), doc);
        writer.close();
    }
}

新增索引

控制台

删除索引

控制台输出

合并前

合并后

注意：

大数据时用合并前的删除，知识给索引文件打标，定时清理打标的索引文件。

数据量不是特别大的时候，可以及时删除索引文件。

修改索引

通过可视化工具可发现

注意：5.3的版本修改前的分词不会消失。

文档域加权

相关代码：

package com.liuwenwu.lucene;

import java.io.StringReader;
import java.nio.file.Paths;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.IntField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
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.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.apache.lucene.search.highlight.SimpleSpanFragmenter;
import org.apache.lucene.store.FSDirectory;
import org.junit.Before;
import org.junit.Test;

/**
 * 中文分词器
 * 高亮显示
 * @author ASUS
 *
 */
public class Demo7 {
    private Integer ids[] = { 1, 2, 3 };
    private String citys[] = { "青岛", "南京", "上海" };
    // private String descs[]={
    // "青岛是个美丽的城市。",
    // "南京是个有文化的城市。",
    // "上海市个繁华的城市。"
    // };
    private String descs[] = { "青岛是个美丽的城市。",
            "南京是一个文化的城市南京，简称宁，是江苏省会，地处中国东部地区，长江下游，濒江近海。全市下辖11个区，总面积6597平方公里，2013年建成区面积752.83平方公里，常住人口818.78万，其中城镇人口659.1万人。[1-4] “江南佳丽地，金陵帝王州”，南京拥有着6000多年文明史、近2600年建城史和近500年的建都史，是中国四大古都之一，有“六朝古都”、“十朝都会”之称，是中华文明的重要发祥地，历史上曾数次庇佑华夏之正朔，长期是中国南方的政治、经济、文化中心，拥有厚重的文化底蕴和丰富的历史遗存。[5-7] 南京是国家重要的科教中心，自古以来就是一座崇文重教的城市，有“天下文枢”、“东南第一学”的美誉。截至2013年，南京有高等院校75所，其中211高校8所，仅次于北京上海；国家重点实验室25所、国家重点学科169个、两院院士83人，均居中国第三。[8-10]",
            "上海市个繁华的城市。" };

    private FSDirectory dir;

    /**
     * 每次都生成索引文件
     * 
     * @throws Exception
     */
    @Before
    public void setUp() throws Exception {
        dir = FSDirectory.open(Paths.get("F:\\y2\\lucene\\demo2\\indexDir"));
        IndexWriter indexWriter = getIndexWriter();
        for (int i = 0; i < ids.length; i++) {
            Document doc = new Document();
            doc.add(new IntField("id", ids[i], Field.Store.YES));
            doc.add(new StringField("city", citys[i], Field.Store.YES));
            doc.add(new TextField("desc", descs[i], Field.Store.YES));
            indexWriter.addDocument(doc);
        }
        indexWriter.close();
    }

    /**
     * 获取索引输出流
     * 
     * @return
     * @throws Exception
     */
    private IndexWriter getIndexWriter() throws Exception {
//        Analyzer analyzer = new StandardAnalyzer();
        Analyzer analyzer = new SmartChineseAnalyzer();
        IndexWriterConfig conf = new IndexWriterConfig(analyzer);
        return new IndexWriter(dir, conf);
    }

    /**
     * luke查看索引生成
     * 
     * @throws Exception
     */
    @Test
    public void testIndexCreate() throws Exception {

    }

    /**
     * 测试高亮
     * 
     * @throws Exception
     */
    @Test
    public void testHeight() throws Exception {
        IndexReader reader = DirectoryReader.open(dir);
        IndexSearcher searcher = new IndexSearcher(reader);

        SmartChineseAnalyzer analyzer = new SmartChineseAnalyzer();
        QueryParser parser = new QueryParser("desc", analyzer);
        // Query query = parser.parse("南京文化");
        Query query = parser.parse("南京文明");
        TopDocs hits = searcher.search(query, 100);

        // 查询得分项
        QueryScorer queryScorer = new QueryScorer(query);
        // 得分项对应的内容片段
        SimpleSpanFragmenter fragmenter = new SimpleSpanFragmenter(queryScorer);
        // 高亮显示的样式
        SimpleHTMLFormatter htmlFormatter = new SimpleHTMLFormatter("<span color='red'><b>", "</b></span>");
        // 高亮显示对象
        Highlighter highlighter = new Highlighter(htmlFormatter, queryScorer);
        // 设置需要高亮显示对应的内容片段
        highlighter.setTextFragmenter(fragmenter);

        for (ScoreDoc scoreDoc : hits.scoreDocs) {
            Document doc = searcher.doc(scoreDoc.doc);
            String desc = doc.get("desc");
            if (desc != null) {
                // tokenstream是从doucment的域（field)中抽取的一个个分词而组成的一个数据流，用于分词。
                TokenStream tokenStream = analyzer.tokenStream("desc", new StringReader(desc));
                System.out.println("高亮显示的片段：" + highlighter.getBestFragment(tokenStream, desc));
            }
            System.out.println("所有内容：" + desc);
        }

    }

}

控制台结果：

南京文明结果：

高亮显示的片段：城镇人口659.1万人。[1-4] “江南佳丽地，金陵帝王州”，<span color='red'><b>南京</b></span>拥有着6000多年<span color='red'><b>文明</b></span>史、近2600年建城史和近500年的建都史，
是中国四大古都之一，有“六朝古都”、“十朝都会”之称，是中华<span color='red'><b>文明</b></span>的
所有内容：南京是一个文化的城市南京，简称宁，是江苏省会，地处中国东部地区，长江下游，濒江近海。全市下辖11个区，总面积6597平方公里，2013年建成区面积752.83平方公里，常住人口818.78万，其中城镇人口659.1万人。
[1-4] “江南佳丽地，金陵帝王州”，南京拥有着6000多年文明史、近2600年建城史和近500年的建都史，是中国四大古都之一，有“六朝古都”、“十朝都会”之称，是中华文明的重要发祥地，
历史上曾数次庇佑华夏之正朔，长期是中国南方的政治、经济、文化中心，拥有厚重的文化底蕴和丰富的历史遗存。[5-7] 南京是国家重要的科教中心，自古以来就是一座崇文重教的城市，有“天下文枢”、“东南第一学”的美誉。截至2013年，南京有高等院校75所，其中211高校8所，仅次于北京上海；国家重点实验室25所、国家重点学科169个、两院院士83人，均居中国第三。[8-10]

　　Lucene中各个核心类的作用：https://blog.csdn.net/kevinelstri/article/details/52317977

综合案例

核心代码

<properties>
        <httpclient.version>4.5.2</httpclient.version>
        <jsoup.version>1.10.1</jsoup.version>
        <!-- <lucene.version>7.1.0</lucene.version> -->
        <lucene.version>5.3.1</lucene.version>
        <ehcache.version>2.10.3</ehcache.version>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.16</log4j.version>
        <mysql.version>5.1.44</mysql.version>
        <fastjson.version>1.2.47</fastjson.version>
        <struts2.version>2.5.16</struts2.version>
        <servlet.version>4.0.1</servlet.version>
        <jstl.version>1.2</jstl.version>
        <standard.version>1.1.2</standard.version>
        <tomcat-jsp-api.version>8.0.47</tomcat-jsp-api.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>

        <!-- jdbc驱动包 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
        </dependency>

        <!-- 添加Httpclient支持 -->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>${httpclient.version}</version>
        </dependency>

        <!-- 添加jsoup支持 -->
        <dependency>
            <groupId>org.jsoup</groupId>
            <artifactId>jsoup</artifactId>
            <version>${jsoup.version}</version>
        </dependency>


        <!-- 添加日志支持 -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
        </dependency>

        <!-- 添加ehcache支持 -->
        <dependency>
            <groupId>net.sf.ehcache</groupId>
            <artifactId>ehcache</artifactId>
            <version>${ehcache.version}</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>${fastjson.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-core</artifactId>
            <version>${struts2.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet.version}</version>
            <scope>provided</scope>
        </dependency>


        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-core</artifactId>
            <version>${lucene.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-queryparser</artifactId>
            <version>${lucene.version}</version>
        </dependency>
        <!-- <dependency> <groupId>org.apache.lucene</groupId> <artifactId>lucene-analyzers-common</artifactId> 
            <version>${lucene.version}</version> </dependency> -->

        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-analyzers-smartcn</artifactId>
            <version>${lucene.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-highlighter</artifactId>
            <version>${lucene.version}</version>
        </dependency>

        <!-- 5.3、jstl、standard -->
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>${jstl.version}</version>
        </dependency>
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>${standard.version}</version>
        </dependency>

        <!-- 5.4、tomcat-jsp-api -->
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jsp-api</artifactId>
            <version>${tomcat-jsp-api.version}</version>
        </dependency>
    </dependencies>

package com.liuwenwu.blog.web;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
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.search.highlight.Highlighter;
import org.apache.lucene.store.Directory;
import org.apache.struts2.ServletActionContext;

import com.liuwenwu.blog.dao.BlogDao;
import com.liuwenwu.blog.util.LuceneUtil;
import com.liuwenwu.blog.util.PropertiesUtil;
import com.liuwenwu.blog.util.StringUtils;

/**
 * IndexReader
 * IndexSearcher
 * Highlighter
 * @author Administrator
 *
 */
public class BlogAction {
    private String title;
    private BlogDao blogDao = new BlogDao();

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String list() {
        try {
            HttpServletRequest request = ServletActionContext.getRequest();
            if (StringUtils.isBlank(title)) {
                List<Map<String, Object>> blogList = this.blogDao.list(title, null);
                request.setAttribute("blogList", blogList);
            }else {
                Directory directory = LuceneUtil.getDirectory(PropertiesUtil.getValue("indexPath"));
                DirectoryReader reader = LuceneUtil.getDirectoryReader(directory);
                IndexSearcher searcher = LuceneUtil.getIndexSearcher(reader);
                SmartChineseAnalyzer analyzer = new SmartChineseAnalyzer();
//                拿一句话到索引目中的索引文件中的词库进行关键词碰撞
                Query query = new QueryParser("title", analyzer).parse(title);
                Highlighter highlighter = LuceneUtil.getHighlighter(query, "title");
                
                TopDocs topDocs = searcher.search(query , 100);
                //处理得分命中的文档
                List<Map<String, Object>> blogList = new ArrayList<>();
                Map<String, Object> map = null;
                ScoreDoc[] scoreDocs = topDocs.scoreDocs;
                for (ScoreDoc scoreDoc : scoreDocs) {
                    map = new HashMap<>();
                    Document doc = searcher.doc(scoreDoc.doc);
                    map.put("id", doc.get("id"));
                    String titleHighlighter = doc.get("title");
                    if(StringUtils.isNotBlank(titleHighlighter)) {
                        titleHighlighter = highlighter.getBestFragment(analyzer, "title", titleHighlighter);
                    }
                    map.put("title", titleHighlighter);
                    map.put("url", doc.get("url"));
                    blogList.add(map);
                }
                
                request.setAttribute("blogList", blogList);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "blogList";
    }
}

package com.liuwenwu.blog.web;

import java.io.IOException;
import java.nio.file.Paths;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;

import org.apache.lucene.analysis.cn.smart.SmartChineseAnalyzer;
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.store.Directory;
import org.apache.lucene.store.FSDirectory;

import com.liuwenwu.blog.dao.BlogDao;
import com.liuwenwu.blog.util.PropertiesUtil;


/**
 * 构建lucene索引
 * @author Administrator
 * 1。构建索引    IndexWriter
 * 2、读取索引文件，获取命中片段
 * 3、使得命中片段高亮显示
 *
 */
public class IndexStarter {
    private static BlogDao blogDao = new BlogDao();
    public static void main(String[] args) {
        IndexWriterConfig conf = new IndexWriterConfig(new SmartChineseAnalyzer());
        Directory d;
        IndexWriter indexWriter = null;
        try {
            d = FSDirectory.open(Paths.get(PropertiesUtil.getValue("indexPath")));
            indexWriter = new IndexWriter(d , conf );
            
//            为数据库中的所有数据构建索引
            List<Map<String, Object>> list = blogDao.list(null, null);
            for (Map<String, Object> map : list) {
                Document doc = new Document();
                doc.add(new StringField("id", (String) map.get("id"), Field.Store.YES));
//                TextField用于对一句话分词处理    java培训机构
                doc.add(new TextField("title", (String) map.get("title"), Field.Store.YES));
                doc.add(new StringField("url", (String) map.get("url"), Field.Store.YES));
                indexWriter.addDocument(doc);
            }
            
        } catch (IOException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            try {
                if(indexWriter!= null) {
                    indexWriter.close();
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

package com.liuwenwu.blog.util;

import java.io.IOException;
import java.nio.file.Paths;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.highlight.Formatter;
import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.QueryTermScorer;
import org.apache.lucene.search.highlight.Scorer;
import org.apache.lucene.search.highlight.SimpleFragmenter;
import org.apache.lucene.search.highlight.SimpleHTMLFormatter;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.RAMDirectory;

/**
 * lucene工具类
 * @author Administrator
 *
 */
public class LuceneUtil {

    /**
     * 获取索引文件存放的文件夹对象
     * 
     * @param path
     * @return
     */
    public static Directory getDirectory(String path) {
        Directory directory = null;
        try {
            directory = FSDirectory.open(Paths.get(path));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return directory;
    }

    /**
     * 索引文件存放在内存
     * 
     * @return
     */
    public static Directory getRAMDirectory() {
        Directory directory = new RAMDirectory();
        return directory;
    }

    /**
     * 文件夹读取对象
     * 
     * @param directory
     * @return
     */
    public static DirectoryReader getDirectoryReader(Directory directory) {
        DirectoryReader reader = null;
        try {
            reader = DirectoryReader.open(directory);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return reader;
    }

    /**
     * 文件索引对象
     * 
     * @param reader
     * @return
     */
    public static IndexSearcher getIndexSearcher(DirectoryReader reader) {
        IndexSearcher indexSearcher = new IndexSearcher(reader);
        return indexSearcher;
    }

    /**
     * 写入索引对象
     * 
     * @param directory
     * @param analyzer
     * @return
     */
    public static IndexWriter getIndexWriter(Directory directory, Analyzer analyzer)

    {
        IndexWriter iwriter = null;
        try {
            IndexWriterConfig config = new IndexWriterConfig(analyzer);
            config.setOpenMode(OpenMode.CREATE_OR_APPEND);
            // Sort sort=new Sort(new SortField("content", Type.STRING));
            // config.setIndexSort(sort);//排序
            config.setCommitOnClose(true);
            // 自动提交
            // config.setMergeScheduler(new ConcurrentMergeScheduler());
            // config.setIndexDeletionPolicy(new
            // SnapshotDeletionPolicy(NoDeletionPolicy.INSTANCE));
            iwriter = new IndexWriter(directory, config);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return iwriter;
    }

    /**
     * 关闭索引文件生成对象以及文件夹对象
     * 
     * @param indexWriter
     * @param directory
     */
    public static void close(IndexWriter indexWriter, Directory directory) {
        if (indexWriter != null) {
            try {
                indexWriter.close();
            } catch (IOException e) {
                indexWriter = null;
            }
        }
        if (directory != null) {
            try {
                directory.close();
            } catch (IOException e) {
                directory = null;
            }
        }
    }

    /**
     * 关闭索引文件读取对象以及文件夹对象
     * 
     * @param reader
     * @param directory
     */
    public static void close(DirectoryReader reader, Directory directory) {
        if (reader != null) {
            try {
                reader.close();
            } catch (IOException e) {
                reader = null;
            }
        }
        if (directory != null) {
            try {
                directory.close();
            } catch (IOException e) {
                directory = null;
            }
        }

    }

    /**
     * 高亮标签
     * 
     * @param query
     * @param fieldName
     * @return
     */

    public static Highlighter getHighlighter(Query query, String fieldName)
    {
        Formatter formatter = new SimpleHTMLFormatter("<span style='color:red'>", "</span>");
        Scorer fragmentScorer = new QueryTermScorer(query, fieldName);
        Highlighter highlighter = new Highlighter(formatter, fragmentScorer);
        highlighter.setTextFragmenter(new SimpleFragmenter(200));
        return highlighter;
    }
}

原文地址：https://www.cnblogs.com/xiatian3452/p/11572950.html