导入依赖：

        <dependency>
            <groupId>org.elasticsearch.client</groupId>
            <artifactId>elasticsearch-rest-high-level-client</artifactId>
            <version>7.12.1</version>
        </dependency>

导入依赖成功之后就可以开始我们的测试了！！！

RestClient操作索引库

创建RestClient

在测试方法中进行测试，首先我们需要创建一个RestHighLevelClient，使用@BeforeEach注解进行create，使用@AfterEach关闭链接。然后我们打印client

 	private RestHighLevelClient client;

    /**
     * BeforeEach注解是指，在执行其他测试方法之前，必须先执行一次该方法
     */
    @BeforeEach
    void setUp() {
        client = new RestHighLevelClient(RestClient.builder(
                HttpHost.create("http://公网ip:9200")
        ));
    }

    /**
     * AfterEach注解是指，在执行其他测试方法之后，必须先执行一次该方法
     */
    @AfterEach
    void tearDown() throws IOException {
        client.close();
    }

新增索引库

1. 创建Request对象
2. 准备请求的参数：DSL语句
3. 发生请求

    @Test
    void createHotelIndex() throws IOException {
        // 1. 创建Request对象
        CreateIndexRequest request = new CreateIndexRequest("user");
        // 2. 准备请求的参数：DSL语句
        request.source("{\n" +
                "  \"mappings\": {\n" +
                "    \"properties\": {\n" +
                "      \"id\": {\n" +
                "        \"type\": \"keyword\"\n" +
                "      },\n" +
                "      \"name\": {\n" +
                "        \"type\": \"text\",\n" +
                "        \"analyzer\": \"ik_max_word\"\n" +
                "      }\n" +
                "    }\n" +
                "  }\n" +
                "}", XContentType.JSON);
        // 3. 发生请求
        client.indices().create(request, RequestOptions.DEFAULT);
    }

运行成功后我们回到Dev Tools查询

GET /usr

删除和查看索引库

    @Test
    void deleteHotelIndex() throws IOException {
        DeleteIndexRequest request = new DeleteIndexRequest("user");
        client.indices().delete(request, RequestOptions.DEFAULT);
    }

    @Test
    void existsHotelIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("user");
        boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists ? "索引库已经存在" : "索引库不存在");
    }

RestClient操作文档

准备工作

这里我们配合mysql来完成文档的操作，要使用mybatis-plus，所以给该测试类加上@SpringBootTest，并注入相应的mapper或者service。
user的sql语句

DROP TABLE IF EXISTS `tb_user`;
CREATE TABLE `tb_user`  (
  `id` bigint(25) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 12 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;

INSERT INTO `tb_user` VALUES (1, 'zhangsan');
INSERT INTO `tb_user` VALUES (2, 'lisi');
INSERT INTO `tb_user` VALUES (3, 'wangwu');
INSERT INTO `tb_user` VALUES (4, 'zhaoliu');
INSERT INTO `tb_user` VALUES (5, 'xiaomei');
INSERT INTO `tb_user` VALUES (6, 'xiaobai');
INSERT INTO `tb_user` VALUES (7, 'at');
INSERT INTO `tb_user` VALUES (8, 'sh');
INSERT INTO `tb_user` VALUES (9, 'wsgp');
INSERT INTO `tb_user` VALUES (10, 'iop');
INSERT INTO `tb_user` VALUES (11, 'askdhgk');

user实体类

package cn.itcast.hotel.pojo;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

@Data
@TableName("tb_user")
public class User {
    @TableId(type = IdType.INPUT)
    private Long id;
    private String Name;
}

UserMapper类

package cn.itcast.hotel.mapper;

import cn.itcast.hotel.pojo.User;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;

public interface UserMapper extends BaseMapper<User> {
}

单个文档插入

    @Test
    void addDoc() throws IOException {
        User user = userMapper.selectById(1);
        System.out.println(user);
        IndexRequest request = new IndexRequest("user").id(user.getId().toString());
        request.source(JSON.toJSONString(user), XContentType.JSON);
        client.index(request, RequestOptions.DEFAULT);
    }

查看是否插入成功：

查询文档

    @Test
    void getDoc() throws IOException {
        GetRequest request = new GetRequest("user", "1");
        GetResponse response = client.get(request, RequestOptions.DEFAULT);
        String json = response.getSourceAsString();
        User user = JSON.parseObject(json, User.class);
        System.out.println(user);
    }

更新和删除文档

这里有全量更新和局部更新，全量更新就和插入文档一样，所以这里只介绍局部更新。

    /**
     * 局部更新
     */
    @Test
    void updateDoc() throws IOException {
        UpdateRequest request = new UpdateRequest("user", "1");
        request.doc(
                "name", "zs"
        );
        client.update(request, RequestOptions.DEFAULT);
    }
    
    /**
     * 删除指定文档
     * @throws IOException
     */
    @Test
    void deleteDoc() throws IOException {
        DeleteRequest request = new DeleteRequest("user", "1");
        client.delete(request, RequestOptions.DEFAULT);
    }

批量插入文档

    /**
     * 批量插入
     * @throws IOException
     */
    @Test
    void addDocBulk() throws IOException {
        List<User> users = userMapper.selectList(null);

        BulkRequest request = new BulkRequest();
        for (User user : users) {
            request.add(new IndexRequest("test")
                    .id(user.getId().toString())
                    .source(JSON.toJSONString(user), XContentType.JSON)
            );
        }
        client.bulk(request, RequestOptions.DEFAULT);
    }