lucene基础

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>Test</groupId>
    <artifactId>Test</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <name>Test Maven Webapp</name>
    <url>http://maven.apache.org</url>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.4</version>
        </dependency>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-api</artifactId>
            <version>7.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-core</artifactId>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-queryparser</artifactId>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-analyzers-common</artifactId>
            <version>5.0.0</version>
        </dependency>
    </dependencies>
    
</project>

package com.newtouchone.lucene;

import static org.junit.Assert.assertEquals;


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.index.IndexableField;
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.RAMDirectory;

public class LuceneDemo {

    public static void main(String[] args) throws Exception {
        Analyzer analyzer = new StandardAnalyzer();//解析器，用于将文档中的单词进行处理减少索引空间、同时也会对查询单词进行处理
        // Store the index in memory:
        Directory directory = new RAMDirectory();//打开内存空间
        // To store an index on disk, use this instead:
        // Directory directory = FSDirectory.open("/tmp/testindex");//打开本地磁盘
        IndexWriterConfig config = new IndexWriterConfig(analyzer);//配置写入流的解析器
        IndexWriter iwriter = new IndexWriter(directory, config);//indexwriter是索引写入的流
        
        Document doc = new Document();//建立文档
        String text = "This is the text to be indexed.";//需要保存的写入的内容
        doc.add(new Field("body", text, TextField.TYPE_STORED));//文档的一个属性（field），这里我写入body->内容
        doc.add(new Field("title","first", TextField.TYPE_STORED));//title->first
        iwriter.addDocument(doc);//索引里面添加此文档
        String text2 = "learning lecene";//同理上面
        Document doc2 = new Document();
        doc2.add(new Field("body", text2, TextField.TYPE_STORED));
        doc.add(new Field("title","second", TextField.TYPE_STORED));
        iwriter.addDocument(doc2);
        
        iwriter.close();//关闭索引流
        

        // Now search the index://搜索
        DirectoryReader ireader = DirectoryReader.open(directory); //打开索引地址
        IndexSearcher isearcher = new IndexSearcher(ireader);//创建搜索器
        // Parse a simple query that searches for "text":
        QueryParser parser = new QueryParser("body", analyzer);//在body里面进行搜索，简单来说就是搜索文档内容（我定义的文档是title和body（内容））
        Query query = parser.parse("indexed");//搜索含有index的文档
        ScoreDoc[] hits = isearcher.search(query, null, 1000).scoreDocs;//拿到命中结果

        assertEquals(1, hits.length);//验证
        
        // Iterate through the results:读取结果
        for (int i = 0; i < hits.length; i++) {for (IndexableField indexableField : hitDoc.getFields()) {//一个文档可以有多个field的，比如说我这次的文档有title和body
                System.out.println(indexableField.stringValue());//读取filed的内容
            }
        }
        ireader.close();
        directory.close();
    }

}

This is the text to be indexed.
first