ElasticSearch在JavaAPI中的操作(入门)

Posted 周大仙1

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目录

2.2.5 Java API 操作

(1)环境准备&创建ES客户端

(2)ES索引创建

(3)ES索引&查询&删除

(4)文档 新增&修改

新增

修改数据

(5)文档的批量新增&批量删除

批量新增

批量删除

(6)高级查询&全量查询

全量查询

(7)高级查询&分页查询&条件查询&字段查询

条件查询

分页查询

排序

包含和排除

​编辑

(8)高级查询&组合查询&范围查询组合查询

范围查询

(9)高级查询&模糊查询&高亮查询

模糊查询

高亮查询

(10)高级查询&聚合查询&分组查询

聚合查询

 分组查询


2.2.5 Java API 操作

ES软件是由Java语言开发的,所以也可以通过Java API的方式对ES服务进行访问

需要添加的依赖如下

<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>

(1)环境准备&创建ES客户端

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

import java.io.IOException;

//es创建客户端对象
public class EsDemo1 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        System.out.println(client);
        client.close();
    

(2)ES索引创建

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
import org.elasticsearch.action.admin.indices.create.CreateIndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;

import java.io.IOException;

//Es索引创建
public class EsDemo2 
    public static void main(String[] args) throws IOException 
        //创建客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http")));

        // 创建索引 - 请求对象
        CreateIndexRequest request = new CreateIndexRequest("root");
        // 发送请求,获取响应
        CreateIndexResponse response = client.indices().create(request,
                RequestOptions.DEFAULT);
        boolean acknowledged = response.isAcknowledged();
        // 响应状态
        System.out.println("操作状态 = " + acknowledged);

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

 响应结果为:root索引创建完成

(3)ES索引&查询&删除

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexAction;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.support.master.AcknowledgedResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.client.indices.GetIndexResponse;

import java.io.IOException;

//Es索引  查询  删除
public class EsDemo3 
    public static void main(String[] args) throws IOException 
        // 创建客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http")));

        // 查询索引 - 请求对象
        GetIndexRequest request = new GetIndexRequest("root");
        // 发送请求,获取响应
        GetIndexResponse response = client.indices().get(request,
                RequestOptions.DEFAULT);

        System.out.println("aliases:"+response.getAliases());
        System.out.println("mappings:"+response.getMappings());
        System.out.println("settings:"+response.getSettings());
        //删除索引

//        AcknowledgedResponse delete = delete(client);
//        System.out.println(delete.isAcknowledged());
        client.close();

    
    public static AcknowledgedResponse delete(RestHighLevelClient client) throws IOException 
        DeleteIndexRequest request2 = new DeleteIndexRequest("root");
        AcknowledgedResponse response2 = client.indices().delete(request2, RequestOptions.DEFAULT);
        return response2;
    

查询结果为

如果想要删除索引,将上面注释取消即可

(4)文档 新增&修改

新增

package com.jt.popj;

import lombok.Data;

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

package com.jt.test;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.jt.config.ConnectElasticsearch;
import com.jt.popj.User;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.xcontent.XContentType;

//新增
public class EsDemo5 
    public static void main(String[] args) 
        ConnectElasticsearch.connect(client -> 
            //新增文档 --请求对象
            IndexRequest request = new IndexRequest();
            //设置索引 唯一标识
            request.index("root").id("1001");

            //创建数据对象
            User user = new User();
            user.setAge(18);
            user.setName("张飞");
            user.setSex("男");

            ObjectMapper objectMapper = new ObjectMapper();
            String productJson  = objectMapper.writeValueAsString(user);
            //添加文档数据,格式为json
            request.source(productJson, XContentType.JSON);
            //客户端发送请求,获取相应对象
            IndexResponse response = client.index(request, RequestOptions.DEFAULT);

            System.out.println("索引:"+response.getIndex());
            System.out.println("id:"+response.getId());
            System.out.println("数据"+response.getResult());
        );
    

修改数据

package com.jt.test;

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;

import java.io.IOException;

//修改数据
public class EsDemo6 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //修改数据
        UpdateRequest request = new UpdateRequest();
        request.index("root").id("1001");
        request.doc(XContentType.JSON,"sex","女");
        UpdateResponse response = esClient.update(request , RequestOptions.DEFAULT);
        System.out.println(response.getResult());
        esClient.close();
    

检测修改的结果

package com.jt.test;

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

import java.io.IOException;

public class EsDemo7 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        GetRequest request = new GetRequest();
        request.index("root").id("1001");
        GetResponse reponse = esClient.get(request, RequestOptions.DEFAULT);
        System.out.println(reponse.getSourceAsString());

        esClient.close();
    

(5)文档的批量新增&批量删除

批量新增

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;

import java.io.IOException;

//批量新增和批量删除
public class EsDemo8 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        BulkRequest request = new BulkRequest();
        request.add(new IndexRequest().index("root").id("1002").source(XContentType.JSON,"name","刘备"));
        request.add(new IndexRequest().index("root").id("1002").source(XContentType.JSON,"name","赵云"));
        request.add(new IndexRequest().index("root").id("1002").source(XContentType.JSON,"name","关羽"));
        BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.getTook());//花费的时间
        System.out.println(response.getItems());//响应信息
        esClient.close();
    

批量删除

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.xcontent.XContentType;

import java.io.IOException;

//批量新增和批量删除
public class EsDemo8 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        BulkRequest request = new BulkRequest();
        request.add(new DeleteRequest().index("root").id("1002"));
        request.add(new DeleteRequest().index("root").id("1002"));
        request.add(new DeleteRequest().index("root").id("1002"));
        BulkResponse response = esClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.getTook());//花费的时间
        System.out.println(response.getItems());//响应信息
        esClient.close();
    

(6)高级查询&全量查询

全量查询

package com.jt.test;

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.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

//高级查询&全量查询
public class EsDemo9 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");
        //全量查询
        request.source(new SearchSourceBuilder().query(QueryBuilders.matchAllQuery()));//全量匹配
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        System.out.println(hits.getTotalHits()); //条数
        System.out.println(response.getTook()); //时间

        for (SearchHit hit:hits)
            String sourceAsString = hit.getSourceAsString();
            System.out.println(sourceAsString);
        
    

查询结果

(7)高级查询&分页查询&条件查询&字段查询

条件查询

         RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");

        request.source(new SearchSourceBuilder().query(QueryBuilders.termQuery("age",26)));//查询条件:age=26
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();

        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
        //全量查询

分页查询

 from()括号中的参数: (页码数-1)*每页显式的条数    也就是size里面的参数

排序

 只需要在size().sort()就可以

包含和排除

 响应结果


(8)高级查询&组合查询&范围查询
组合查询

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

//高级查询&组合查询&范围查询
public class EsDemo11 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");

        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();  //创建组合查询构造器
//        boolQueryBuilder.must(QueryBuilders.matchQuery("age",25));  //must等价于and 两者都满足
//        boolQueryBuilder.must(QueryBuilders.matchQuery("sex","男"));
//        boolQueryBuilder.mustNot(QueryBuilders.matchQuery("sex","男"));//mustnot 两者都不满足
//        boolQueryBuilder.mustNot(QueryBuilders.matchQuery("age",25));

        boolQueryBuilder.should(QueryBuilders.matchQuery("sex","男"));//should等价于or  其中有一个条件满足就可以
        boolQueryBuilder.should(QueryBuilders.matchQuery("age",25));
        builder.query(boolQueryBuilder);    //将组合构造器加入查询构造器
        request.source(builder);    //查询构造器加入查询请求
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

范围查询

package com.jt.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

//高级查询&组合查询&范围查询
public class EsDemo11 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");

        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
        RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("age"); //范围查询rangeQuery,参数为字段
        rangeQueryBuilder.gte(22);//>= 22
        rangeQueryBuilder.lte(28);// <= 28
        builder.query(rangeQueryBuilder); //将范围查询构造器加入查询构造器
        request.source(builder);    //查询构造器加入查询请求
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

(9)高级查询&模糊查询&高亮查询

模糊查询

package com.jt.test;

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.common.unit.Fuzziness;
import org.elasticsearch.index.query.FuzzyQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;
//高级查询&模糊查询&高亮查询
public class EsDemo12 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");

        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
        FuzzyQueryBuilder fuzzyQueryBuilder = QueryBuilders //模糊查询  Fuzziness.ONE  匹配多一个字符。比如:关羽1  x关羽  关x羽....
                .fuzzyQuery("name", "关羽").fuzziness(Fuzziness.ONE);
        builder.query(fuzzyQueryBuilder);
        request.source(builder);
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

高亮查询

package com.jt.test;

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.common.unit.Fuzziness;
import org.elasticsearch.index.query.FuzzyQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.TermQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;

import java.io.IOException;

public class EsDemo12 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");
        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
        TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("sex", "男");
        HighlightBuilder highlightBuilder = new HighlightBuilder();//创建高亮构造器
        highlightBuilder.preTags("<font color = 'red'>");
        highlightBuilder.postTags("</font>");
        highlightBuilder.field("sex");

        builder.highlighter(highlightBuilder);//高亮构造器加入查询构造器中
        builder.query(termQueryBuilder);
        request.source(builder);
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

(10)高级查询&聚合查询&分组查询

聚合查询

package com.jt.test;

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.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilder;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.metrics.AvgAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

//聚合查询和分组查询
public class EsDemo13 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");
        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
        AggregationBuilder aggregationBuilder = AggregationBuilders.max("maxAge").field("age");//自定义最大值名字 maxAge
        builder.aggregation(aggregationBuilder);
        request.source(builder);
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

查询结果

 分组查询

package com.jt.test;

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.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilder;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.metrics.AvgAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;

import java.io.IOException;

//聚合查询和分组查询
public class EsDemo13 
    public static void main(String[] args) throws IOException 
        RestHighLevelClient esClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        //查询数据
        SearchRequest request = new SearchRequest();
        request.indices("root");
        SearchSourceBuilder builder = new SearchSourceBuilder();    //创建查询构造器
      //  AggregationBuilder aggregationBuilder = AggregationBuilders.max("maxAge").field("age");//自定义最大值名字 maxAge
        AggregationBuilder aggregationBuilder = AggregationBuilders.terms("ageGroup").field("age");//自定义最大值名字 maxAge
        builder.aggregation(aggregationBuilder);
        request.source(builder);
        SearchResponse response = esClient.search(request, RequestOptions.DEFAULT);
        SearchHits hits = response.getHits();
        for (SearchHit hit:hits)
            System.out.println(hit.getSourceAsString());
        
        esClient.close();
    

查询结果为

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Elasticsearch7.8.0版本入门——JavaAPI操作(批量操作文档)