Elasticsearch7.8.0版本入门——JavaAPI操作（分组统计文档）

Posted 2023-02-21 小志的博客

目录

• • 一、pom文件依赖
  • 二、首先，批量创建文档（添加假数据，方便查询操作）
  • 三、分组统计文档的代码示例

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、首先，批量创建文档（添加假数据，方便查询操作）

• 参考此博文链接：https://wwwxz.blog.csdn.net/article/details/128824820

三、分组统计文档的代码示例

• 分组统计文档代码示例

  package com.xz.esdemo.day7;
  
  import org.apache.http.HttpHost;
  import org.elasticsearch.action.search.SearchRequest;
  import org.elasticsearch.action.search.SearchResponse;
  import org.elasticsearch.client.RequestOptions;
  import org.elasticsearch.client.RestClient;
  import org.elasticsearch.client.RestHighLevelClient;
  import org.elasticsearch.search.SearchHits;
  import org.elasticsearch.search.aggregations.AggregationBuilders;
  import org.elasticsearch.search.builder.SearchSourceBuilder;
  
  /**
   * @description: 分组统计文档
   * @author: xz
   */
  public class EsDocGroupbyQuery 
      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"))
          );
  
          // 创建搜索请求对象
          SearchRequest request = new SearchRequest();
          request.indices("user");
  
          // 构建查询的请求体
          SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
          sourceBuilder.aggregation(AggregationBuilders.terms("age_groupby").field("age"));
  
          //设置请求体
          request.source(sourceBuilder);
  
          // 客户端发送请求，获取响应对象
          SearchResponse response = client.search(request, RequestOptions.DEFAULT);
          SearchHits hits = response.getHits();
          System.out.println(response);
  
          // 关闭 es 客户端连接
          client.close();
      
  
  

• 执行代码，查看控制台信息，如下图表示分组统计文档成功。