Elasticsearch7.8.0版本入门——JavaAPI操作（文档操作）

news2024/11/16 19:32:02

一、pom文件依赖

引入相关依赖

<!-- elasticsearch 依赖 -->
<dependency>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>7.8.0</version>
</dependency>
<!-- elasticsearch 的客户端 -->
<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.8.0</version>
</dependency>
<!-- elasticsearch 依赖 2.x 的 log4j -->
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <version>2.8.2</version>
</dependency>
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-core</artifactId>
    <version>2.8.2</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.9.9</version>
</dependency>
<!-- junit 单元测试 -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>

二、创建实体对象类

创建实体对象

package com.xz.esdemo.day2;

import lombok.Data;

@Data
public class User {
    private String name;
    private Integer age;
    private String sex;
}

三、文档操作代码示例

3.1、创建文档代码示例

创建文档代码示例

package com.xz.esdemo.day2;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.HttpHost;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;
/**
 * @description: 创建文档
 * @author: xz
 */
public class EsDocCreate {
    public static void main(String[] args) throws Exception{
        // 创建 es 客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 新增文档 - 请求对象
        IndexRequest indexRequest = new IndexRequest();
        // 设置索引及唯一性标识
        indexRequest.index("user").id("01");

        // 创建数据对象
        User user = new User();
        user.setName("zhangsan");
        user.setAge(20);
        user.setSex("男");
        ObjectMapper objectMapper = new ObjectMapper();
        String productJson = objectMapper.writeValueAsString(user);
        // 添加文档数据，数据格式为 JSON 格式
        indexRequest.source(productJson, XContentType.JSON);
        // 客户端发送请求，获取响应对象
        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
        System.out.println("_index:" + response.getIndex());
        System.out.println("_id:" + response.getId());
        System.out.println("_result:" + response.getResult());

        // 关闭 es 客户端连接
        client.close();
    }
}

执行代码，查看控制台信息，如下图表示创建文档成功。
通过postman工具查看创建的文档信息，如下图所示：

3.2、修改文档代码示例

修改文档代码示例

package com.xz.esdemo.day2;

import org.apache.http.HttpHost;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;

/**
 * @description: 修改文档
 * @author: xz
 */
public class EsDocUpdate {
    public static void main(String[] args) throws Exception{
        // 创建 es 客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 新增文档 - 请求对象
        UpdateRequest updateRequest = new UpdateRequest();
        // 设置索引及唯一性标识
        updateRequest.index("user").id("01");
        // 设置请求体，对数据进行修改
        updateRequest.doc(XContentType.JSON, "sex", "女");

        // 客户端发送请求，获取响应对象
        UpdateResponse response = client.update(updateRequest, RequestOptions.DEFAULT);
        System.out.println("_index:" + response.getIndex());
        System.out.println("_id:" + response.getId());
        System.out.println("_result:" + response.getResult());

        // 关闭 es 客户端连接
        client.close();
    }
}

执行代码，查看控制台信息，如下图表示创建文档成功。
通过postman工具查看创建的文档信息，如下图所示：

3.3、查询文档代码示例

查询文档代码示例

package com.xz.esdemo.day2;

import org.apache.http.HttpHost;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

/**
 * @description: 查询文档
 * @author: xz
 */
public class EsDocGet {
    public static void main(String[] args) throws Exception{
        // 创建 es 客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 新增文档 - 请求对象
        GetRequest getRequest = new GetRequest();
        // 设置索引及唯一性标识
        getRequest.index("user").id("01");

        // 客户端发送请求，获取响应对象
        GetResponse response = client.get(getRequest, RequestOptions.DEFAULT);
        System.out.println("_index:" + response.getIndex());
        System.out.println("_type:" + response.getType());
        System.out.println("_id:" + response.getId());
        System.out.println("source:" + response.getSourceAsString());

        // 关闭 es 客户端连接
        client.close();
    }
}

执行代码，查看控制台信息，如下图表示创建文档成功。

3.4、删除文档代码示例

删除文档代码示例

package com.xz.esdemo.day2;

import org.apache.http.HttpHost;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

/**
 * @description: 删除文档
 * @author: xz
 */
public class EsDocDelete {
    public static void main(String[] args) throws Exception{
        // 创建 es 客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http"))
        );

        // 新增文档 - 请求对象
        DeleteRequest deleteRequest = new DeleteRequest();
        // 设置索引及唯一性标识
        deleteRequest.index("user").id("01");

        // 客户端发送请求，获取响应对象
        DeleteResponse response = client.delete(deleteRequest, RequestOptions.DEFAULT);
        System.out.println(response.toString());

        // 关闭 es 客户端连接
        client.close();
    }
}