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  • ElasticSearch集成SpringBoot与常见使用方法

    目录

    一、导包

    image-20200531214301211

    二、核对导入的ES版本

    我的springboot自动导入的是7.6.2的版本，但我搭建的ES是7.7.0，为了避免出异常，需修改导入版本与ES服务版本一致

    image-20200531214554301

    修改导入版本

    1. 查看springboot版本号使用的什么properties标签

      • 打开pom文件->按住ctrl点击artifactId

      image-20200605140346085

      • 在弹出的pom中按住Ctrl点击artifactId

        image-20200531215033287

      • 在弹出的pom中找到elasticsearch版本标签

        image-20200531215150952

      • 在项目的pom文件properties标签中添加需要导入的版本

        image-20200531215247205

      • 这时回到刚才第一张图，看es就会变成了指定的版本了

    三、写配置类

    我是用的是RestHighLevelClient ，通过官方文档得知，它需要返回一个RestHighLevelClient 对象，并且使用完后及时关闭客户端

    image-20200531220239292

    • 我的配置类

      package com.rb.elasticsearch.elasticsearch.conf;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class EsConf {
    @Bean
    public RestHighLevelClient restHighLevelClient(){
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(
                        //new HttpHost("localhost", 9200, "http"),//如果集群，传入多个地址即可
                        new HttpHost("192.168.100.112", 9200, "http")));//我的ES地址端口
        return client;
    }
}
//可以自己写一个自动装配类，将ip写入Yml文件

    四、开始测试

    索引操作

    1.创建索引

    注意：索引名字必须小写

    返回值为：{"acknowledged":true,"fragment":false,"shardsAcknowledged":true}

    这个返回值和elasticsearch-head创建索引返回的结果一样

    image-20200531222346753

    代码如下：

    package com.rb.elasticsearch.elasticsearch;

import com.alibaba.fastjson.JSON;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.CreateIndexResponse;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.io.IOException;

@SpringBootTest
class ElasticsearchApplicationTests {
    @Autowired
    RestHighLevelClient restHighLevelClient;

    /**
     * 创建索引
     * @throws IOException
     */
    @Test
    void createIndex() throws IOException {
        CreateIndexRequest request = new CreateIndexRequest("java_index");
        CreateIndexResponse createIndexResponse =restHighLevelClient.indices().create(request, RequestOptions.DEFAULT);
        System.out.println(JSON.toJSONString(createIndexResponse));//返回值
    }

}

    2.查看索引是否存在

        /**
     * 判断索引是否存在
     * @throws IOException
     */
    @Test
    void checkIndex() throws IOException {
        GetIndexRequest getIndexRequest=new GetIndexRequest("java_index");
        boolean exists = restHighLevelClient.indices().exists(getIndexRequest, RequestOptions.DEFAULT);
        System.out.println(exists);//返回值true:存在 false:不存在
    }

    3.删除索引

    acknowledged=true表示删除成功

        /**
     * 判断索引是否存在
     * @throws IOException
     */
    @Test
    void delIndex() throws IOException {
        DeleteIndexRequest deleteIndexRequest=new DeleteIndexRequest("java_index");
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
        System.out.println(JSON.toJSONString(delete));//返回值{"acknowledged":true,"fragment":false}
    }

    文档操作

    官方举例是手拼json串，但工作中很少这么用，大多数都是一个model，然后转成json串，所以先创建一个model

    package com.rb.elasticsearch.model;

import lombok.Data;

@Data
public class Users {
    String name;
    String remark;
    int age;
}

    1.添加文档

    • 单条添加

      /**
     * 添加文档
     */
@Test
void putDoc() throws IOException {
    if(checkIndexIsExist()){//这个方法见下方“查看文档是否存在” 如果不判断是否存在，在没有创建索引的情况下，它会创建索引
        IndexRequest indexRequest=new IndexRequest(Es.INDEX_NAME);
        indexRequest.id("1");
        Users users=new Users();
        users.setAge(15);
        users.setName("张三的名字叫张三");
        users.setRemark("张三的备注");
        indexRequest.source(JSON.toJSONString(users), XContentType.JSON);
        IndexResponse index = restHighLevelClient.index(indexRequest, RequestOptions.DEFAULT);
        System.out.println(JSON.toJSONString(index));
    }else{
        System.out.println("索引不存在");
    }
}

    • 批量添加

       /**
     * 批量添加
     * @throws IOException
     */
    @Test
    void bulkAddDoc() throws IOException {
        if(checkIndexIsExist()){//如果不判断是否存在，在没有创建索引的情况下，它会创建索引
            BulkRequest request=new BulkRequest();
            for (int i = 0; i <5 ; i++) {//循环添加五个
                int id = i+1;
                IndexRequest indexRequest=new IndexRequest(Es.INDEX_NAME);
                Users users=new Users();
                users.setRemark("李"+i+"的备注");
                users.setName("李"+i+"的名字叫李"+i);
                users.setAge(i);
                indexRequest.source(JSON.toJSONString(users),XContentType.JSON);
                indexRequest.id(String.valueOf(id));
                request.add(indexRequest);
            }
            BulkResponse bulk = restHighLevelClient.bulk(request, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(bulk));
        }
    }

    2.查看文档是否存在

        /**
     * 查看文档是否存在
     * @throws IOException
     */
    @Test
    void checkDocIsExist() throws IOException {
        if(checkIndexIsExist()){
            GetRequest getRequest=new GetRequest(Es.INDEX_NAME,"1");
            boolean exists = restHighLevelClient.exists(getRequest, RequestOptions.DEFAULT);
            System.out.println(exists);//true 存在 false 不存在
        }else{
            System.out.println("索引不存在");
        }
    }

    3.修改文档

    注意：我的users对象中age是int,默认值是0，如果执行下面批量修改的时候，age不修改的话会默认是0，这样会将相关索引中age字段值全部修改为0，可以使用Integer

    • 单一修改
     /**
     * 单一修改数据
     * @throws IOException
     */
    @Test
    void updateDoc() throws IOException {
        if(checkIndexIsExist()){
            UpdateRequest updateRequest=new UpdateRequest(Es.INDEX_NAME,"1");
            Users users=new Users();
            users.setAge(99);//只修改年龄，其他不动
            updateRequest.doc(JSON.toJSONString(users),XContentType.JSON);
            restHighLevelClient.update(updateRequest,RequestOptions.DEFAULT);
        }
    }

    • 批量修改

      /**
     * 批量修改数据
     * @throws IOException
     */
    @Test
    void buleUpdateDoc() throws IOException {
        if(checkIndexIsExist()){
            BulkRequest bulkRequest=new BulkRequest();
            for (int i = 0; i <5 ; i++) {
                int id =i+1;
                UpdateRequest updateRequest=new UpdateRequest(Es.INDEX_NAME,String.valueOf(id));
                Users users=new Users();
                users.setRemark("批量修改的备注"+i);
                updateRequest.doc(JSON.toJSONString(users),XContentType.JSON);
                bulkRequest.add(updateRequest);
            }
            restHighLevelClient.bulk(bulkRequest,RequestOptions.DEFAULT);
        }
    }

    4.删除文档

    • 单独删除
        /**
     * 删除文档
     * @throws IOException
     */
    @Test
    void delDoc() throws IOException {
        if(checkIndexIsExist()){//只有索引已经创建的时候才可以继续
            DeleteRequest deleteRequest=new DeleteRequest("java_index","1");
            DeleteResponse delete = restHighLevelClient.delete(deleteRequest, RequestOptions.DEFAULT);
            System.out.println(delete);
        }
    }
    • 批量删除
    /**
     * 批量删除
     * @throws IOException
     */
    @Test
    void buleDelDoc() throws IOException {
        if(checkIndexIsExist()){
            BulkRequest bulkRequest=new BulkRequest();
            for (int i = 0; i <5 ; i++) {
                int id =i+1;
                DeleteRequest deleteRequest=new DeleteRequest(Es.INDEX_NAME);
                deleteRequest.id(String.valueOf(id));
                bulkRequest.add(deleteRequest);
            }
            restHighLevelClient.bulk(bulkRequest,RequestOptions.DEFAULT);
        }
    }

    五.文档常用查询

    单一字段查询

    根据id精准查询

     /**
     * 根据id查询
     * @throws IOException
     */
    @Test
    void termSelectById() throws IOException {
        if(checkIndexIsExist()){
            GetRequest getRequest1 = new GetRequest(Es.INDEX_NAME, "1");
            //也可使用下面的方式
            //GetRequest getRequest=new GetRequest(Es.INDEX_NAME);
            //getRequest.id("1");
            GetResponse documentFields = restHighLevelClient.get(getRequest1, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(documentFields));
        }
    }

    根据某字段精准查询

    （select * from users where age=1）

      /**
       * 根据某字段精准查询
       * @throws IOException
       */
      @Test
      void termSelectByField() throws IOException {
          if(checkIndexIsExist()){
              SearchRequest searchRequest=new SearchRequest(Es.INDEX_NAME);
              SearchSourceBuilder searchSourceBuilder=new SearchSourceBuilder();
              searchSourceBuilder.query(QueryBuilders.termQuery("age",1));
              searchRequest.source(searchSourceBuilder);
              SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
              System.out.println(JSON.toJSONString(search));
          }
      }

    根据某字段模糊查询

    （select * from users where remark like '%0%'）

    /**
     * 根据某个字段模糊查询
     * @throws IOException
     */
    @Test
    void matchSelectByField() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest=new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder=new SearchSourceBuilder();
            searchSourceBuilder.query(QueryBuilders.matchQuery("remark","0"));
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    多条件查询

    多条件And查询

    (select * from users where name like '%因为是match，会被分词%' and age=0)

        /**
     * 多条件查询
     * @throws IOException
     */
    @Test
    void multipleFieldSelectByMust() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);//定义请求
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();//构建查询条件器
            BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();//选择返回值（满足查询条件的返回true，不满足是false）
            boolQueryBuilder.must(QueryBuilders.matchQuery("name","李0的名字叫李0"));//查询条件一
            boolQueryBuilder.must(QueryBuilders.termQuery("age","0"));//查询条件二
            System.out.println(boolQueryBuilder.must());//输出构建好的查询条件一、二
            searchSourceBuilder.query(boolQueryBuilder);//将条件完善的对象放入
            searchRequest.source(searchSourceBuilder);//向查询请求中放入查询条件
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);//执行查询
            System.out.println(JSON.toJSONString(search.getHits().getHits()));//查看结果
        }
    }

    这一步我认为有点绕，java代码逻辑和上一篇说的命令先后逻辑是一样的,我的研究方式为逆推法（自己这么起的名字）

    • 第一步：restHighLevelClient.search先把这个敲出来，发现这个方法需要一个SearchRequest对象

    • 第二步：new 一个 SearchRequest 这个对象，然后命令顺序下一步是“query”，我就找到了searchSourceBuilder.query()方法，重复第一步，发现query方法需要一个BoolQueryBuilder对象

    • 第三步：new 一个 BoolQueryBuilder这个对象，然后重复第二步，观察命令顺序，这时会传入mustmust_not等信息，我就在官方提供的QueryBuilders中找到了相应的方法boolQueryBuilder.must()

      • 这时，我发现一个卡点，命令上会传入一个多条件数组，java中肯定会传入一个多条件的对象，但是没有在QueryBuilders找到入参为数组的， 愁坏我了，去官网翻了一下，看到了下图，意思是可多调用多次，然后我就调用了两次image-20200606231726697

    • 第四步：因为第三步不确定，但是BoolQueryBuilder这个类中却有返回一个数组的方法，调用看看

      System.out.println(boolQueryBuilder.must());//输出构建好的查询条件一、二

    • 结果和我想的一样，成功了

    • 为了加深上面的印象，我将这块命令顺序同步标记了一下java代码的位置，更方便理解：

    GET users/_doc/_search //后的_search就是 SearchRequest 定义请求
{
  "query":{//searchSourceBuilder.query(boolQueryBuilder);//将条件完善的对象放入
    "bool":{//BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();//选择返回值（满足查询条件的返回true，不满足是false）
      "must":[//boolQueryBuilder.must()
        {
          "term"://QueryBuilders.termQuery("age","0");每调用一次就多一个查询条件
          {
            "name":"张三的名字叫张三"
          }
        } , 
         {
          "match"://QueryBuilders.matchQuery("name","李0的名字叫李0")
          {
            "age":"15"
          }
        }
      ]
    }
  }
}

    多条件OR查询

    (select * from users where remark like '%1%' or age=0) 注：%1%里的1使用了match，会被分词

    /**
     * 多条件查询OR
     * @throws IOException
     */
    @Test
    void multipleFieldSelectByShould() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
            boolQueryBuilder.should(QueryBuilders.matchQuery("remark","1"));
            boolQueryBuilder.should(QueryBuilders.termQuery("age","0"));
            searchSourceBuilder.query(boolQueryBuilder);
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    多条件！=查询

    (select * from users where age !=0 and age !=1)

    /**
     * 多条件查询！=
     * @throws IOException
     */
    @Test
    void multipleFieldSelectByMustNot() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
            boolQueryBuilder.mustNot(QueryBuilders.termQuery("age","1"));//QueryBuilders里面的查询方式可以随意换
            boolQueryBuilder.mustNot(QueryBuilders.termQuery("age","0"));//QueryBuilders里面的查询方式可以随意换
            searchSourceBuilder.query(boolQueryBuilder);
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    范围查询

    (select * from users where age >=0 and age <=2)

    gt 大于
    gte 大于等于
    lt 小于
    lte 小于等于！

     /**
     * 根据字段范围查询
     * @throws IOException
     */
    @Test
    void multipleFieldSelectByRange() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
            //再此处还可以加上面的各种查询条件↓↓↓
            //再此处还可以加上面的各种查询条件↑↑↑
            boolQueryBuilder.filter(QueryBuilders.rangeQuery("age").gte(0));
            boolQueryBuilder.filter(QueryBuilders.rangeQuery("age").lte(2));
            searchSourceBuilder.query(boolQueryBuilder);
            searchRequest.source(searchSourceBuilder);
            restHighLevelClient.search(searchRequest,RequestOptions.DEFAULT);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    自定义字段返回

        /**
     * 显示指定字段
     * @throws IOException
     */
    @Test
    void returnField() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            String[] includeFields = new String[] {"name", "age"};//要显示的哪些字段
            String[] excludeFields = new String[] {""};//要排除的哪些字段
            searchSourceBuilder.fetchSource(includeFields,excludeFields);
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    排序

    select * from users where remark like '%的备注%' and remark like '%3%' order by _score desc , age desc

    查询包含“的备注”、“3”的记录（传入参数会被分词），并且按照匹配度_score这个字段排序，数值越大的匹配度越高，然后按照年龄age降序排序

    /**
     * 排序
     * @throws IOException
     */
    @Test
    void sort() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest = new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            searchSourceBuilder.query(QueryBuilders.matchQuery("remark","的备注 3"));
            searchSourceBuilder.sort("_score",SortOrder.DESC);
            searchSourceBuilder.sort("age",SortOrder.DESC);
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search));
        }
    }

    高亮查询

    public String test() throws IOException {
        SearchRequest searchRequest=new SearchRequest(Es.INDEX_NAME);
        SearchSourceBuilder searchSourceBuilder=new SearchSourceBuilder();
        //构建查询条件start
        searchSourceBuilder.query(QueryBuilders.matchQuery("name","名 叫"));//模糊搜索
        //searchSourceBuilder.query(QueryBuilders.termQuery("name.keyword","李0的名字叫李0"));//精准搜索
        //构建查询条件end
        //高亮start
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("name");
        //highlightBuilder.field("name.keyword");//与上方设置的name保持一致
        highlightBuilder.preTags("<mytag style='color:red'>");//自定义标签&样式
        highlightBuilder.postTags("</mytag>");//自定义标签&样式
        searchSourceBuilder.highlighter(highlightBuilder);
        //高亮end
        searchRequest.source(searchSourceBuilder);
        SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
        List<Map<String, Object>> list=new ArrayList();
        //高亮条件封装start
        for (SearchHit hit : search.getHits().getHits()) {
            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
            HighlightField remark = highlightFields.get("name");
           // HighlightField remark = highlightFields.get("name.keyword");//与上方设置的name保持一致
            Map<String, Object> sourceAsMap = hit.getSourceAsMap();
            if(remark!=null){
                Text[] fragments = remark.fragments();
                String desc="";
                for (Text fragment : fragments) {
                    desc+=fragment;
                }
                //sourceAsMap.put("name.keyword",desc);
                sourceAsMap.put("name",desc);
                list.add(sourceAsMap);
            }
        }
        //高亮条件封装end
        return JSON.toJSONString(search);
    }

    结果如下：

    image-20200607171409906

    获得指定索引下满足条件的总记录数据

        /**
     * 查询指定索引中总共有多少条数据
     * @throws IOException
     */
    @Test
    void getTotalCount() throws IOException {
        CountRequest countRequest = new CountRequest(Es.INDEX_NAME);
        //可以自定义设置上面的一些查询条件start
        //可以自定义设置上面的一些查询条件end
        CountResponse count = restHighLevelClient.count(countRequest, RequestOptions.DEFAULT);
        System.out.println(JSON.toJSONString(count));
    }

    分页查询

    from:从第几条数据开始(>关系，非>=)
    size:查询几条数据

    /**
     * 分页查询
     * @throws IOException
     */
    @Test
    void pageSelect() throws IOException {
        if(checkIndexIsExist()){
            SearchRequest searchRequest=new SearchRequest(Es.INDEX_NAME);
            SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
            //设置搜索条件
            searchSourceBuilder.query(QueryBuilders.matchQuery("remark","的备注"));
            searchSourceBuilder.from(2);//从索引第几个开始查找，索引从0 开始
            searchSourceBuilder.size(2);//显示from至from+size的数据
            //例如：查询id1~2的数据，from=0 ，size=2
            //     查询id3-4的数据，from=2,  size=2
            searchRequest.source(searchSourceBuilder);
            SearchResponse search = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
            System.out.println(JSON.toJSONString(search.getHits().getHits()));
        }
    }

    六、集成好的项目

    https://files-cdn.cnblogs.com/files/rb2010/elasticsearch.zip
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  • 原文地址：https://www.cnblogs.com/rb2010/p/13061353.html
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