ElasticSearch教程入门到精通——第二部分(基于ELK技术栈elasticsearch 7.x+8.x新特性)

ElasticSearch教程入门到精通——第二部分(基于ELK技术栈elasticsearch 7.x+8.x新特性)

  • 1. JavaAPI-环境准备
    • 1.1 新建Maven工程——添加依赖
    • 1.2 HelloElasticsearch
  • 2. 索引
    • 2.1 索引——创建
    • 2.2 索引——查询
    • 2.3 索引——删除
  • 3. 文档
    • 3.1 文档——重构
    • 3.2 文档——新增
    • 3.3 文档——修改
    • 3.4 文档——简单操作
      • 3.4.1 文档——简单查询
      • 3.4.2 文档——简单删除
    • 3.5 文档——批量操作
      • 3.5.1 文档——批量新增
      • 3.5.2 文档——批量删除
    • 3.6 文档——高级查询
      • 3.6.1 文档——高级查询——全量查询
      • 3.6.2 文档——高级查询——条件查询
      • 3.6.3 文档——高级查询——分页查询
      • 3.6.4 文档——高级查询——查询排序
      • 3.6.5 文档——高级查询——组合查询
      • 3.6.6 文档——高级查询——范围查询
      • 3.6.7 文档——高级查询——模糊查询
      • 3.6.9 文档——高级查询——高亮查询
      • 3.6.10 文档——高级查询——最大值查询
      • 3.6.11 文档——高级查询——分组查询

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1. JavaAPI-环境准备

1.1 新建Maven工程——添加依赖

<dependencies>
    <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>
</dependencies>

1.2 HelloElasticsearch

import java.io.IOException;

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

public class HelloElasticsearch {

	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")));
//		...
		System.out.println(client);

		// 关闭客户端连接
		client.close();
	}
}

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2. 索引

2.1 索引——创建

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

import java.io.IOException;

public class ESTest_Index_Create {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        // 创建索引
        CreateIndexRequest createIndexRequest = new CreateIndexRequest("user");
        CreateIndexResponse createIndexResponse = restHighLevelClient.indices().create(createIndexRequest, RequestOptions.DEFAULT);

        boolean acknowledged = createIndexResponse.isAcknowledged();
        System.out.println("acknowledged = " + acknowledged);
        restHighLevelClient.close();
    }
}

后台打印:

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2.2 索引——查询

package com.atguigu.es.test;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.client.indices.CreateIndexResponse;
import org.elasticsearch.client.indices.GetIndexRequest;
import org.elasticsearch.client.indices.GetIndexResponse;
import org.elasticsearch.cluster.metadata.AliasMetadata;
import org.elasticsearch.cluster.metadata.MappingMetadata;
import org.elasticsearch.common.settings.Settings;

import java.io.IOException;
import java.util.List;
import java.util.Map;

public class ESTest_Index_Search {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        // 查询索引
        GetIndexRequest getIndexRequest = new GetIndexRequest("user");

        GetIndexResponse getIndexResponse = restHighLevelClient.indices().get(getIndexRequest, RequestOptions.DEFAULT);

        Map<String, List<AliasMetadata>> aliases = getIndexResponse.getAliases();
        System.out.println("aliases = " + aliases);
        Map<String, MappingMetadata> mappings = getIndexResponse.getMappings();
        System.out.println("mappings = " + mappings);
        Map<String, Settings> settings = getIndexResponse.getSettings();
        System.out.println("settings = " + settings);


        restHighLevelClient.close();
    }
}

后台打印:

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2.3 索引——删除

package com.atguigu.es.test;

import org.apache.http.HttpHost;
import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
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 org.elasticsearch.cluster.metadata.AliasMetadata;
import org.elasticsearch.cluster.metadata.MappingMetadata;
import org.elasticsearch.common.settings.Settings;

import java.io.IOException;
import java.util.List;
import java.util.Map;

public class ESTest_Index_Delete {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient restHighLevelClient = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost",9200,"http"))
        );
        // 删除索引
        DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("user");
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);

        boolean acknowledged = delete.isAcknowledged();
        System.out.println("acknowledged = " + acknowledged);


        restHighLevelClient.close();
    }
}

后台打印:

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3. 文档

3.1 文档——重构

上文由于频繁使用以下连接Elasticsearch和关闭它的代码,于是个人对它进行重构。

public class SomeClass {
    public static void main(String[] args) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http")));
		
        ...
        
        client.close();
    }
}

重构后的代码:

import org.elasticsearch.client.RestHighLevelClient;

public interface ElasticsearchTask {

    void doSomething(RestHighLevelClient client) throws Exception;

}
public class ConnectElasticsearch{

    public static void connect(ElasticsearchTask task){
        // 创建客户端对象
        RestHighLevelClient client = new RestHighLevelClient(
                RestClient.builder(new HttpHost("localhost", 9200, "http")));
        try {
            task.doSomething(client);
            // 关闭客户端连接
            client.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

接下来,如果想让Elasticsearch完成一些操作,就编写一个lambda式即可。

public class SomeClass {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
			//do something
        });
    }
}

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3.2 文档——新增

import com.fasterxml.jackson.databind.ObjectMapper;
import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.model.User;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.xcontent.XContentType;

public class InsertDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            // 新增文档 - 请求对象
            IndexRequest request = new IndexRequest();
            // 设置索引及唯一性标识
            request.index("user").id("1001");

            // 创建数据对象
            User user = new User();
            user.setName("zhangsan");
            user.setAge(30);
            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
            request.source(productJson, XContentType.JSON);
            // 客户端发送请求,获取响应对象
            IndexResponse response = client.index(request, RequestOptions.DEFAULT);
            3.打印结果信息
            System.out.println("_index:" + response.getIndex());
            System.out.println("_id:" + response.getId());
            System.out.println("_result:" + response.getResult());
        });
    }
}

后台打印:

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3.3 文档——修改

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.action.update.UpdateResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.xcontent.XContentType;

public class UpdateDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            // 修改文档 - 请求对象
            UpdateRequest request = new UpdateRequest();
            // 配置修改参数
            request.index("user").id("1001");
            // 设置请求体,对数据进行修改
            request.doc(XContentType.JSON, "sex", "女");
            // 客户端发送请求,获取响应对象
            UpdateResponse response = client.update(request, RequestOptions.DEFAULT);
            System.out.println("_index:" + response.getIndex());
            System.out.println("_id:" + response.getId());
            System.out.println("_result:" + response.getResult());
        });
    }

}

后台打印:

_index:user
_id:1001
_result:UPDATED

Process finished with exit code 0

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3.4 文档——简单操作

3.4.1 文档——简单查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import org.elasticsearch.action.get.GetRequest;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.client.RequestOptions;

public class GetDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            //1.创建请求对象
            GetRequest request = new GetRequest().index("user").id("1001");
            //2.客户端发送请求,获取响应对象
            GetResponse response = client.get(request, RequestOptions.DEFAULT);
            3.打印结果信息
            System.out.println("_index:" + response.getIndex());
            System.out.println("_type:" + response.getType());
            System.out.println("_id:" + response.getId());
            System.out.println("source:" + response.getSourceAsString());
        });
    }
}

后台打印:

_index:user
_type:_doc
_id:1001
source:{"name":"zhangsan","age":30,"sex":"男"}

Process finished with exit code 0

3.4.2 文档——简单删除

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.client.RequestOptions;

public class DeleteDoc {
    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            //创建请求对象
            DeleteRequest request = new DeleteRequest().index("user").id("1001");
            //客户端发送请求,获取响应对象
            DeleteResponse response = client.delete(request, RequestOptions.DEFAULT);
            //打印信息
            System.out.println(response.toString());
        });
    }
}

后台打印:

DeleteResponse[index=user,type=_doc,id=1001,version=16,result=deleted,shards=ShardInfo{total=2, successful=1, failures=[]}]

Process finished with exit code 0

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3.5 文档——批量操作

3.5.1 文档——批量新增

import com.lun.elasticsearch.hello.ConnectElasticsearch;
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.common.xcontent.XContentType;

public class BatchInsertDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            //创建批量新增请求对象
            BulkRequest request = new BulkRequest();
            request.add(new
                    IndexRequest().index("user").id("1001").source(XContentType.JSON, "name",
                    "zhangsan"));
            request.add(new
                    IndexRequest().index("user").id("1002").source(XContentType.JSON, "name",
                            "lisi"));
            request.add(new
                    IndexRequest().index("user").id("1003").source(XContentType.JSON, "name",
                    "wangwu"));
            //客户端发送请求,获取响应对象
            BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
            //打印结果信息
            System.out.println("took:" + responses.getTook());
            System.out.println("items:" + responses.getItems());
        });
    }
}

后台打印

took:294ms
items:[Lorg.elasticsearch.action.bulk.BulkItemResponse;@2beee7ff

Process finished with exit code 0

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3.5.2 文档——批量删除

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import org.elasticsearch.action.bulk.BulkRequest;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.client.RequestOptions;

public class BatchDeleteDoc {
    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            //创建批量删除请求对象
            BulkRequest request = new BulkRequest();
            request.add(new DeleteRequest().index("user").id("1001"));
            request.add(new DeleteRequest().index("user").id("1002"));
            request.add(new DeleteRequest().index("user").id("1003"));
            //客户端发送请求,获取响应对象
            BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
            //打印结果信息
            System.out.println("took:" + responses.getTook());
            System.out.println("items:" + responses.getItems());
        });
    }
}

后台打印

took:108ms
items:[Lorg.elasticsearch.action.bulk.BulkItemResponse;@7b02881e

Process finished with exit code 0

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3.6 文档——高级查询

3.6.1 文档——高级查询——全量查询

先批量增加数据

public class BatchInsertDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            //创建批量新增请求对象
            BulkRequest request = new BulkRequest();
            request.add(new IndexRequest().index("user").id("1001").source(XContentType.JSON, "name", "zhangsan", "age", "10", "sex","女"));
            request.add(new IndexRequest().index("user").id("1002").source(XContentType.JSON, "name", "lisi", "age", "30", "sex","女"));
            request.add(new IndexRequest().index("user").id("1003").source(XContentType.JSON, "name", "wangwu1", "age", "40", "sex","男"));
            request.add(new IndexRequest().index("user").id("1004").source(XContentType.JSON, "name", "wangwu2", "age", "20", "sex","女"));
            request.add(new IndexRequest().index("user").id("1005").source(XContentType.JSON, "name", "wangwu3", "age", "50", "sex","男"));
            request.add(new IndexRequest().index("user").id("1006").source(XContentType.JSON, "name", "wangwu4", "age", "20", "sex","男"));
            //客户端发送请求,获取响应对象
            BulkResponse responses = client.bulk(request, RequestOptions.DEFAULT);
            //打印结果信息
            System.out.println("took:" + responses.getTook());
            System.out.println("items:" + responses.getItems());
        });
    }
}

后台打印

took:168ms
items:[Lorg.elasticsearch.action.bulk.BulkItemResponse;@2beee7ff

Process finished with exit code 0

查询所有索引数据

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;

public class QueryDoc {

    public static void main(String[] args) {
        ConnectElasticsearch.connect(client -> {
            // 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();
            // 查询所有数据
            sourceBuilder.query(QueryBuilders.matchAllQuery());
            request.source(sourceBuilder);
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 查询匹配
            SearchHits hits = response.getHits();
            System.out.println("took:" + response.getTook());
            System.out.println("timeout:" + response.isTimedOut());
            System.out.println("total:" + hits.getTotalHits());
            System.out.println("MaxScore:" + hits.getMaxScore());
            System.out.println("hits========>>");
            for (SearchHit hit : hits) {
            //输出每条查询的结果信息
                System.out.println(hit.getSourceAsString());
            }
            System.out.println("<<========");
        });
    }

}

后台打印

took:2ms
timeout:false
total:6 hits
MaxScore:1.0
hits========>>
{"name":"zhangsan","age":"10","sex":"女"}
{"name":"lisi","age":"30","sex":"女"}
{"name":"wangwu1","age":"40","sex":"男"}
{"name":"wangwu2","age":"20","sex":"女"}
{"name":"wangwu3","age":"50","sex":"男"}
{"name":"wangwu4","age":"20","sex":"男"}
<<========

Process finished with exit code 0

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3.6.2 文档——高级查询——条件查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
	public static final ElasticsearchTask SEARCH_BY_CONDITION = client -> {
        // 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.query(QueryBuilders.termQuery("age", "30"));
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");
    };
    
    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_BY_CONDITION);
    }
}

后台打印

took:1ms
timeout:false
total:1 hits
MaxScore:1.0
hits========>>
{"name":"lisi","age":"30","sex":"女"}
<<========

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3.6.3 文档——高级查询——分页查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
	public static final ElasticsearchTask SEARCH_BY_PAGING = client -> {
        // 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.query(QueryBuilders.matchAllQuery());
        // 分页查询
        // 当前页其实索引(第一条数据的顺序号), from
        sourceBuilder.from(0);

        // 每页显示多少条 size
        sourceBuilder.size(2);
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");
    };
    
    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_BY_CONDITION);
    }

}

后台打印

took:1ms
timeout:false
total:6 hits
MaxScore:1.0
hits========>>
{"name":"zhangsan","age":"10","sex":"女"}
{"name":"lisi","age":"30","sex":"女"}
<<========

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3.6.4 文档——高级查询——查询排序

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
	public static final ElasticsearchTask SEARCH_WITH_ORDER = client -> {
        // 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.query(QueryBuilders.matchAllQuery());
        // 排序
        sourceBuilder.sort("age", SortOrder.ASC);
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
        //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");
    };

    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_WITH_ORDER);
    }

}

后台打印

took:1ms
timeout:false
total:6 hits
MaxScore:NaN
hits========>>
{"name":"zhangsan","age":"10","sex":"女"}
{"name":"wangwu2","age":"20","sex":"女"}
{"name":"wangwu4","age":"20","sex":"男"}
{"name":"lisi","age":"30","sex":"女"}
{"name":"wangwu1","age":"40","sex":"男"}
{"name":"wangwu3","age":"50","sex":"男"}
<<========

在这里插入图片描述

3.6.5 文档——高级查询——组合查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
	public static final ElasticsearchTask SEARCH_BY_BOOL_CONDITION = client -> {
        // 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();
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
        // 必须包含
        boolQueryBuilder.must(QueryBuilders.matchQuery("age", "30"));
        // 一定不含
        boolQueryBuilder.mustNot(QueryBuilders.matchQuery("name", "zhangsan"));
        // 可能包含
        boolQueryBuilder.should(QueryBuilders.matchQuery("sex", "男"));
        sourceBuilder.query(boolQueryBuilder);
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");

    };

    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_BY_BOOL_CONDITION);
    }
}

后台打印

took:28ms
timeout:false
total:1 hits
MaxScore:1.0
hits========>>
{"name":"lisi","age":"30","sex":"女"}
<<========

Process finished with exit code 0

在这里插入图片描述

3.6.6 文档——高级查询——范围查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.index.query.BoolQueryBuilder;
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 org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
	public static final ElasticsearchTask SEARCH_BY_RANGE = client -> {
        // 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();
        RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("age");
        // 大于等于
        //rangeQuery.gte("30");
        // 小于等于
        rangeQuery.lte("40");
        sourceBuilder.query(rangeQuery);
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
        //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");
    };

    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_BY_RANGE);
    }

}

后台打印

took:1ms
timeout:false
total:5 hits
MaxScore:1.0
hits========>>
{"name":"zhangsan","age":"10","sex":"女"}
{"name":"lisi","age":"30","sex":"女"}
{"name":"wangwu1","age":"40","sex":"男"}
{"name":"wangwu2","age":"20","sex":"女"}
{"name":"wangwu4","age":"20","sex":"男"}
<<========

Process finished with exit code 0

在这里插入图片描述

3.6.7 文档——高级查询——模糊查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.index.query.BoolQueryBuilder;
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 org.elasticsearch.search.sort.SortOrder;

public class QueryDoc {
    
    public static final ElasticsearchTask SEARCH_BY_FUZZY_CONDITION = client -> {
        // 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.query(QueryBuilders.fuzzyQuery("name","wangwu").fuzziness(Fuzziness.ONE));
        request.source(sourceBuilder);
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        // 查询匹配
        SearchHits hits = response.getHits();
        System.out.println("took:" + response.getTook());
        System.out.println("timeout:" + response.isTimedOut());
        System.out.println("total:" + hits.getTotalHits());
        System.out.println("MaxScore:" + hits.getMaxScore());
        System.out.println("hits========>>");
        for (SearchHit hit : hits) {
            //输出每条查询的结果信息
            System.out.println(hit.getSourceAsString());
        }
        System.out.println("<<========");
    };


    public static void main(String[] args) {
//        ConnectElasticsearch.connect(SEARCH_ALL);
//        ConnectElasticsearch.connect(SEARCH_BY_CONDITION);
//        ConnectElasticsearch.connect(SEARCH_BY_PAGING);
//        ConnectElasticsearch.connect(SEARCH_WITH_ORDER);
//        ConnectElasticsearch.connect(SEARCH_BY_BOOL_CONDITION);
//        ConnectElasticsearch.connect(SEARCH_BY_RANGE);
        ConnectElasticsearch.connect(SEARCH_BY_FUZZY_CONDITION);
    }

}

后台打印

took:152ms
timeout:false
total:4 hits
MaxScore:1.2837042
hits========>>
{"name":"wangwu1","age":"40","sex":"男"}
{"name":"wangwu2","age":"20","sex":"女"}
{"name":"wangwu3","age":"50","sex":"男"}
{"name":"wangwu4","age":"20","sex":"男"}
<<========

Process finished with exit code 0

在这里插入图片描述

3.6.9 文档——高级查询——高亮查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.index.query.TermsQueryBuilder;
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 org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;

import java.util.Map;

public class QueryDoc {
    
    public static final ElasticsearchTask SEARCH_WITH_HIGHLIGHT = client -> {
        // 高亮查询
        SearchRequest request = new SearchRequest().indices("user");
        //2.创建查询请求体构建器
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        //构建查询方式:高亮查询
        TermsQueryBuilder termsQueryBuilder =
                QueryBuilders.termsQuery("name","zhangsan");
        //设置查询方式
        sourceBuilder.query(termsQueryBuilder);
        //构建高亮字段
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.preTags("<font color='red'>");//设置标签前缀
        highlightBuilder.postTags("</font>");//设置标签后缀
        highlightBuilder.field("name");//设置高亮字段
        //设置高亮构建对象
        sourceBuilder.highlighter(highlightBuilder);
        //设置请求体
        request.source(sourceBuilder);
        //3.客户端发送请求,获取响应对象
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        //4.打印响应结果
        SearchHits hits = response.getHits();
        System.out.println("took::"+response.getTook());
        System.out.println("time_out::"+response.isTimedOut());
        System.out.println("total::"+hits.getTotalHits());
        System.out.println("max_score::"+hits.getMaxScore());
        System.out.println("hits::::>>");
        for (SearchHit hit : hits) {
            String sourceAsString = hit.getSourceAsString();
            System.out.println(sourceAsString);
            //打印高亮结果
            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
            System.out.println(highlightFields);
        }
        System.out.println("<<::::");
    };


    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_WITH_HIGHLIGHT);
    }

}

后台打印

took::672ms
time_out::false
total::1 hits
max_score::1.0
hits::::>>
{"name":"zhangsan","age":"10","sex":"女"}
{name=[name], fragments[[<font color='red'>zhangsan</font>]]}
<<::::

Process finished with exit code 0
12345678910

在这里插入图片描述

3.6.10 文档——高级查询——最大值查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.index.query.TermsQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;

import java.util.Map;

public class QueryDoc {
    
    public static final ElasticsearchTask SEARCH_WITH_MAX = client -> {
        // 高亮查询
        SearchRequest request = new SearchRequest().indices("user");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.aggregation(AggregationBuilders.max("maxAge").field("age"));
        //设置请求体
        request.source(sourceBuilder);
        //3.客户端发送请求,获取响应对象
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        //4.打印响应结果
        SearchHits hits = response.getHits();
        System.out.println(response);
    };

    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_WITH_MAX);
    }

}

后台打印

{"took":16,"timed_out":false,"_shards":{"total":1,"successful":1,"skipped":0,"failed":0},"hits":{"total":{"value":6,"relation":"eq"},"max_score":1.0,"hits":[{"_index":"user","_type":"_doc","_id":"1001","_score":1.0,"_source":{"name":"zhangsan","age":"10","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1002","_score":1.0,"_source":{"name":"lisi","age":"30","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1003","_score":1.0,"_source":{"name":"wangwu1","age":"40","sex":"男"}},{"_index":"user","_type":"_doc","_id":"1004","_score":1.0,"_source":{"name":"wangwu2","age":"20","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1005","_score":1.0,"_source":{"name":"wangwu3","age":"50","sex":"男"}},{"_index":"user","_type":"_doc","_id":"1006","_score":1.0,"_source":{"name":"wangwu4","age":"20","sex":"男"}}]},"aggregations":{"max#maxAge":{"value":50.0}}}

Process finished with exit code 0

在这里插入图片描述

3.6.11 文档——高级查询——分组查询

import com.lun.elasticsearch.hello.ConnectElasticsearch;
import com.lun.elasticsearch.hello.ElasticsearchTask;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.common.unit.Fuzziness;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.index.query.TermsQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;

import java.util.Map;

public class QueryDoc {

	public static final ElasticsearchTask SEARCH_WITH_GROUP = client -> {
        SearchRequest request = new SearchRequest().indices("user");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        sourceBuilder.aggregation(AggregationBuilders.terms("age_groupby").field("age"));
        //设置请求体
        request.source(sourceBuilder);
        //3.客户端发送请求,获取响应对象
        SearchResponse response = client.search(request, RequestOptions.DEFAULT);
        //4.打印响应结果
        SearchHits hits = response.getHits();
        System.out.println(response);
    };

    public static void main(String[] args) {
        ConnectElasticsearch.connect(SEARCH_WITH_GROUP);
    }

}

后台打印

{"took":10,"timed_out":false,"_shards":{"total":1,"successful":1,"skipped":0,"failed":0},"hits":{"total":{"value":6,"relation":"eq"},"max_score":1.0,"hits":[{"_index":"user","_type":"_doc","_id":"1001","_score":1.0,"_source":{"name":"zhangsan","age":"10","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1002","_score":1.0,"_source":{"name":"lisi","age":"30","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1003","_score":1.0,"_source":{"name":"wangwu1","age":"40","sex":"男"}},{"_index":"user","_type":"_doc","_id":"1004","_score":1.0,"_source":{"name":"wangwu2","age":"20","sex":"女"}},{"_index":"user","_type":"_doc","_id":"1005","_score":1.0,"_source":{"name":"wangwu3","age":"50","sex":"男"}},{"_index":"user","_type":"_doc","_id":"1006","_score":1.0,"_source":{"name":"wangwu4","age":"20","sex":"男"}}]},"aggregations":{"lterms#age_groupby":{"doc_count_error_upper_bound":0,"sum_other_doc_count":0,"buckets":[{"key":20,"doc_count":2},{"key":10,"doc_count":1},{"key":30,"doc_count":1},{"key":40,"doc_count":1},{"key":50,"doc_count":1}]}}}

Process finished with exit code 0

在这里插入图片描述

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