一. 引入依赖

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.75</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>

?二. 创建ES配置类

package com.lrs.config;

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;

/**
 * @作者：刘壬杉
 * @创建时间 2022/8/16 16:30
 **/
@Configuration
public class EsConfig {
    @Bean
    public RestHighLevelClient restHighLevelClient(){
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(RestClient.builder(new HttpHost("127.0.0.1",9200,"http")));
        return restHighLevelClient;
    }
}

?三. 关于对文档的操作

首先在测试类中引入RestHighLevelClient对象

@Resource
    private RestHighLevelClient client;

其次准备一个User对象

package com.lrs.entity;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * @作者：刘壬杉
 * @创建时间 2022/8/16 19:21
 **/
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private String id;
    private String name;
    private String address;
    private Integer age;

    public User(String name, String address, Integer age) {
        this.name = name;
        this.address = address;
        this.age = age;
    }
}

3.1 对索引的操作

3.1.1 创建索引

//创建索引
    @Test
    void testCreateIndex() throws IOException {
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("test04");
        CreateIndexResponse createIndexResponse = client.indices().create(createIndexRequest, RequestOptions.DEFAULT);
        System.out.println(createIndexResponse.isAcknowledged());
    }

?运行结果:创建成功返回true

3.1.2 删除索引

//删除索引
    @Test
    void testDeleteIndex() throws Exception{
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("test04");
        AcknowledgedResponse delete = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
        System.out.println(delete.isAcknowledged());
    }

运行结果:删除成功返回true

?3.1.3 判断索引是否存在

//判断索引是否存在
    @Test
    void testExistsIndex() throws Exception{
        GetIndexRequest getIndexRequest = new GetIndexRequest("test04");
        boolean exists = client.indices().exists(getIndexRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

运行结果:存在返回true,不存在返回false.

3.2 对文档的操作

3.2.1 添加文档

//添加文档
    @Test
    void testCreateDoc() throws Exception{
        IndexRequest indexRequest = new IndexRequest("test04");
        indexRequest.id("1");
        indexRequest.source(JSON.toJSONString(new User("张三","北京",25)), XContentType.JSON);
        IndexResponse index = client.index(indexRequest, RequestOptions.DEFAULT);
        System.out.println(index.getResult());
    }

运行结果:添加成功返回 CREATED

3.2.2 查询文档----根据id查询

//查询文档 -- id
    @Test
    void testGetDoc() throws Exception{
        GetRequest getRequest = new GetRequest("test04");
        getRequest.id("1");
        GetResponse documentFields = client.get(getRequest, RequestOptions.DEFAULT);
        System.out.println(documentFields.getSourceAsMap());
    }

运行结果:

3.2.3 判断文档是否存在

//判断文档是否存在
    @Test
    void testExistsDoc() throws Exception{
        GetRequest getRequest = new GetRequest("test04");
        getRequest.id("1");
        boolean exists = client.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

运行结果:存在返回true,不存在返回false.

3.2.4 删除文档

//删除文档
    @Test
    void testDeleteDoc() throws Exception{
        DeleteRequest deleteRequest = new DeleteRequest("test04");
        deleteRequest.id("1");
        DeleteResponse delete = client.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(delete.getResult());
    }

运行结果:删除成功返回 DELETED

3.2.5 修改文档

//修改文档
    @Test
    void testUpdateDoc() throws Exception{
        UpdateRequest updateRequest = new UpdateRequest("test04","1");
        User user = new User();
        user.setName("王五");
        updateRequest.doc(JSON.toJSONString(user),XContentType.JSON);
        UpdateResponse update = client.update(updateRequest, RequestOptions.DEFAULT);
        System.out.println(update.getResult());
    }

运行结果:修改成功返回 UPDATED

3.2.6 批量添加文档

//批量添加文档
    @Test
    void testBulk() throws Exception{
        BulkRequest bulkRequest = new BulkRequest("test04");
        List<User> list = new ArrayList<>();
        list.add(new User("1","张三1","北京1",18));
        list.add(new User("2","张三2","北京2",19));
        list.add(new User("3","张三3","北京3",20));
        list.add(new User("4","张三4","北京4",21));
        list.add(new User("5","张三5","北京5",22));
        list.stream().forEach(item->bulkRequest.add(new IndexRequest().id(item.getId()).source(JSON.toJSONString(item),XContentType.JSON)));
        BulkResponse bulk = client.bulk(bulkRequest, RequestOptions.DEFAULT);
        System.out.println(bulk.hasFailures());
    }

运行结果:???? bulk.hasFailures():判断是否有故障,返回false代表没有故障,添加成功

3.3 复杂查询

复杂查询中包含一个条件对象,条件对象里包含了很多条件,比如分页,高亮,排序,查询指定列,精准匹配,范围查询等等

 //复杂查询
    @Test
    void testSearch() throws Exception{
        SearchRequest searchRequest = new SearchRequest("test04");
        //创建条件对象
        SearchSourceBuilder builder = new SearchSourceBuilder();
        //bool
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery().should(QueryBuilders.matchQuery("name", "3"))
                .should(QueryBuilders.matchQuery("age", 20));
        builder.query(boolQueryBuilder);
        //分页
        builder.from(0);
        builder.size(2);
        //指定列
        String[] includes = {"name","address"};
        String[] excludes = {"id"};
        builder.fetchSource(includes,null);
        //高亮
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("name");
        highlightBuilder.preTags("<font>");
        highlightBuilder.postTags("</font>");
        builder.highlighter(highlightBuilder);
        //排序
        builder.sort("age", SortOrder.ASC);
        searchRequest.source(builder);
        SearchResponse search = client.search(searchRequest, RequestOptions.DEFAULT);
        SearchHit[] hits = search.getHits().getHits();
        Arrays.stream(hits).forEach(item-> System.out.println(item.getSourceAsMap()));
        Arrays.stream(hits).forEach(item-> System.out.println(item.getHighlightFields()));
    }