索引库的查询有两类:

1.使用Query的子类
        1)TerQuery
            根据关键词进行查询.
            需要制定要查询的域及要查询的关键词
        2) RangeQuery
            范围查询

2.使用QueryPaser进行查询
        可以对要查询的内容先分词，然后基于分词的结果进行查询。
        添加一个jar包
        lucene-querypaeser-7.4.0.jar

代码部分如下:

package com.itheima;

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.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.junit.Before;
import org.junit.Test;
import org.wltea.analyzer.lucene.IKAnalyzer;

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

/**
 * @ClassName indexSearch
 * @Description TODO
 * @Author gkz
 * @Date 2019/8/23 18:33
 * @Version 1.0
 **/
public class indexSearch {

    private IndexReader indexReader;

    private IndexSearcher indexSearcher;


    @Before()
    public void initIndexReader() throws IOException {

        indexReader = DirectoryReader.open(FSDirectory.open(new File("E:\\Desktop").toPath()));

        indexSearcher = new IndexSearcher(indexReader);
    }

    @Test
    public void testRangeQuery() throws IOException {
        //创建一个Query对象
        Query query = LongPoint.newRangeQuery("size", 1L, 10000L);

        printResult(query);
    }


    @Test
    public void printResult(Query query) throws IOException {
        //执行查询
        TopDocs topDocs = indexSearcher.search(query, 10);

        System.out.println("总记录数" + topDocs.totalHits);

        ScoreDoc[] scoreDocs = topDocs.scoreDocs;

        for (ScoreDoc scoreDoc : scoreDocs) {
            //取文档id
            int id = scoreDoc.doc;

            //根据id取文档对象
            Document document = indexSearcher.doc(id);

            System.out.println(document.get("name"));
            System.out.println(document.get("path"));
            System.out.println(document.get("size"));

            indexReader.close();
        }
    }


    @Test
    public void testQueryParse()throws Exception{

        //创建一个QueryParser对象,两个参数
        //参数1:默认搜索域,参数2:分析器对象
        QueryParser queryParser=new QueryParser("name",new IKAnalyzer());

        //使用QueryParse对象来创建一个Query对象
        Query query = queryParser.parse("lucene是一个Java开发的全文检索工具包");
        //执行查询
        printResult(query);
    }

}