Lucene-索引库查询

概述

　　对要搜索的信息创建Query查询对象，Lucene会根据Query查询对象生成最终的查询语法，类似关系数据库SQL语法一样，Lucene也有自己的查询语法；

　　可通过两种方法创建查询对象：

　　　　1.使用Lucene提供Query子类；

　　　　2.使用QueryParse解析查询表达式

TermQuery查询

　　通过项查询，TermQuery不使用分析器所以建议匹配不分词的Field域查询，比如订单号，分类ID号等；

　　指定要查询的域和要查询的关键词

package com.wn.Query;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
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.Directory;
import org.apache.lucene.store.FSDirectory;

import java.io.File;
import java.io.IOException;

/*根据域和关键词进行搜索*/
public class TermQuery {
    /*查询索引库*/
    public static void main(String[] args)throws IOException {
        Directory directory= FSDirectory.open(new File("E:\\Lucene\\temp\\index").toPath());
        IndexReader indexReader= DirectoryReader.open(directory);
        IndexSearcher indexSearcher=new IndexSearcher(indexReader);
        //创建查询对象
        Query query=new org.apache.lucene.search.TermQuery(new Term("fieldName","text01.txt"));
        //执行查询
        TopDocs topDocs=indexSearcher.search(query,10);
        System.out.println("查询总数量："+topDocs.totalHits);
        //遍历查询结果
        for (ScoreDoc scoreDoc:topDocs.scoreDocs){
            Document document = indexSearcher.doc(scoreDoc.doc);
            System.out.println(document.get("fieldName"));
            System.out.println(document.get("fieldContent"));
            System.out.println(document.get("fieldPath"));
            System.out.println(document.get("fieldSize"));
            System.out.println("====================================================");
        }
        //关闭资源
        indexSearcher.getIndexReader().close();
    }
}

　　效果实现

　　　　

数值范围查询

package com.wn.Query;

import org.apache.lucene.document.Document;
import org.apache.lucene.document.LongPoint;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
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.Directory;
import org.apache.lucene.store.FSDirectory;

import java.io.File;
import java.io.IOException;

public class testRangeQuery {
    /*数值范围查询*/
    public static void main(String[] args)throws IOException {
        Directory directory= FSDirectory.open(new File("E:\\Lucene\\temp\\index").toPath());
        IndexReader indexReader= DirectoryReader.open(directory);
        IndexSearcher indexSearcher=new IndexSearcher(indexReader);
        //创建查询对象
        Query query= LongPoint.newRangeQuery("fieldSize",0,100);
        //执行查询
        TopDocs topDocs=indexSearcher.search(query,10);
        System.out.println("查询总数量："+topDocs.totalHits);
        //遍历查询结果
        for (ScoreDoc scoreDoc:topDocs.scoreDocs){
            Document document = indexSearcher.doc(scoreDoc.doc);
            System.out.println(document.get("fieldName"));
            System.out.println(document.get("fieldContent"));
            System.out.println(document.get("fieldPath"));
            System.out.println(document.get("fieldSize"));
            System.out.println("====================================================");
        }
        //关闭资源
        indexSearcher.getIndexReader().close();
    }
}

　　效果实现

　　　　

QueryParser查询

　　通过QueryParse也可以创建Query，QueryParser提供一个parse方法，此方法可以直接根据查询语法来查询。Query对象执行的查询语法可通过system.out.println(query);查询。

　　需要使用到分词器，建议创建索引时使用的分词器和查询索引时使用的分词器要一致。需要加入queryParser依赖

package com.wn.Query;

import org.apache.lucene.document.Document;
import org.apache.lucene.document.LongPoint;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
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.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.wltea.analyzer.lucene.IKAnalyzer;

import java.io.File;
import java.io.IOException;

/*搜索條件分詞*/
public class Queryparsers {
    public static void main(String[] args) throws IOException, ParseException {
        Directory directory= FSDirectory.open(new File("E:\\Lucene\\temp\\index").toPath());
        IndexReader indexReader= DirectoryReader.open(directory);
        IndexSearcher indexSearcher=new IndexSearcher(indexReader);
        //创建查询对象
        QueryParser queryParser=new QueryParser("fieldContent",new IKAnalyzer());
        Query query = queryParser.parse("全文检索");
        //执行查询
        TopDocs topDocs=indexSearcher.search(query,10);
        System.out.println("查询总数量："+topDocs.totalHits);
        //遍历查询结果
        for (ScoreDoc scoreDoc:topDocs.scoreDocs){
            Document document = indexSearcher.doc(scoreDoc.doc);
            System.out.println(document.get("fieldName"));
            System.out.println(document.get("fieldContent"));
            System.out.println(document.get("fieldPath"));
            System.out.println(document.get("fieldSize"));
            System.out.println("====================================================");
        }
        //关闭资源
        indexSearcher.getIndexReader().close();
    }
}

　　实现效果