SpringBoot整合ElasticSearch

导入依赖

    org.elasticsearch.client
    elasticsearch-rest-high-level-client
    7.4.2

在spring-boot-dependencies中所依赖的ES版本位6.8.5，要改掉

    1.8
    7.4.2

官方建议把requestOptions创建成单实例

package com.hdb.pingmoweb.search.config;

import org.apache.http.HttpHost;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;


@Configuration
public class PingmoESConfig {
    public static final RequestOptions COMMON_OPTIONS;

    static {
        RequestOptions.Builder builder = RequestOptions.DEFAULT.toBuilder();
        COMMON_OPTIONS = builder.build();
    }

    @Bean
    public RestHighLevelClient esRestClient() {
        RestClientBuilder builder = null;
        // 可以指定多个es
        builder = RestClient.builder(new HttpHost("192.168.19.128", 9200, "http"));
        RestHighLevelClient client = new RestHighLevelClient(builder);
        return client;
    }

}

官方文档：Index API | Java REST Client [7.17] | Elastic

保存数据 

Index API | Java REST Client [7.17] | Elastic

@Test
public void indexData() throws IOException {
    
    // 设置索引
    IndexRequest indexRequest = new IndexRequest ("users");
    indexRequest.id("1");

    User user = new User();
    user.setUserName("张三");
    user.setAge(20);
    user.setGender("男");
    String jsonString = JSON.toJSONString(user);
    
    //设置要保存的内容，指定数据和类型
    indexRequest.source(jsonString, XContentType.JSON);
    
    //执行创建索引和保存数据
    IndexResponse index = client.index(indexRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);

    System.out.println(index);

}

获取数据

 @Test
    public void find() throws IOException {
        // 1 创建检索请求
        SearchRequest searchRequest = new SearchRequest();
        searchRequest.indices("bank");
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        // 构造检索条件
//        sourceBuilder.query();
//        sourceBuilder.from();
//        sourceBuilder.size();
//        sourceBuilder.aggregation();
        sourceBuilder.query(QueryBuilders.matchQuery("address","mill"));
        //AggregationBuilders工具类构建AggregationBuilder
        // 构建第一个聚合条件:按照年龄的值分布
        TermsAggregationBuilder agg1 = AggregationBuilders.terms("agg1").field("age").size(10);// 聚合名称
        // 参数为AggregationBuilder
        sourceBuilder.aggregation(agg1);
        // 构建第二个聚合条件:平均薪资
        AvgAggregationBuilder agg2 = AggregationBuilders.avg("agg2").field("balance");
        sourceBuilder.aggregation(agg2);

        System.out.println("检索条件"+sourceBuilder.toString());

        searchRequest.source(sourceBuilder);

        // 2 执行检索
        SearchResponse response = client.search(searchRequest, PingmoESConfig.COMMON_OPTIONS);
        // 3 分析响应结果
        System.out.println(response.toString());
    }

返回数据

{
	"took": 28,
	"timed_out": false,
	"_shards": {
		"total": 1,
		"successful": 1,
		"skipped": 0,
		"failed": 0
	},
	"hits": {
		"total": {
			"value": 4,
			"relation": "eq"
		},
		"max_score": 5.4032025,
		"hits": [{
			"_index": "bank",
			"_type": "account",
			"_id": "970",
			"_score": 5.4032025,
			"_source": {
				"account_number": 970,
				"balance": 19648,
				"firstname": "Forbes",
				"lastname": "Wallace",
				"age": 28,
				"gender": "M",
				"address": "990 Mill Road",
				"employer": "Pheast",
				"email": "[email protected]",
				"city": "Lopezo",
				"state": "AK"
			}
		}, {
			"_index": "bank",
			"_type": "account",
			"_id": "136",
			"_score": 5.4032025,
			"_source": {
				"account_number": 136,
				"balance": 45801,
				"firstname": "Winnie",
				"lastname": "Holland",
				"age": 38,
				"gender": "M",
				"address": "198 Mill Lane",
				"employer": "Neteria",
				"email": "[email protected]",
				"city": "Urie",
				"state": "IL"
			}
		}, {
			"_index": "bank",
			"_type": "account",
			"_id": "345",
			"_score": 5.4032025,
			"_source": {
				"account_number": 345,
				"balance": 9812,
				"firstname": "Parker",
				"lastname": "Hines",
				"age": 38,
				"gender": "M",
				"address": "715 Mill Avenue",
				"employer": "Baluba",
				"email": "[email protected]",
				"city": "Blackgum",
				"state": "KY"
			}
		}, {
			"_index": "bank",
			"_type": "account",
			"_id": "472",
			"_score": 5.4032025,
			"_source": {
				"account_number": 472,
				"balance": 25571,
				"firstname": "Lee",
				"lastname": "Long",
				"age": 32,
				"gender": "F",
				"address": "288 Mill Street",
				"employer": "Comverges",
				"email": "[email protected]",
				"city": "Movico",
				"state": "MT"
			}
		}]
	},
	"aggregations": {
		"avg#agg2": {
			"value": 25208.0
		},
		"lterms#agg1": {
			"doc_count_error_upper_bound": 0,
			"sum_other_doc_count": 0,
			"buckets": [{
				"key": 38,
				"doc_count": 2
			}, {
				"key": 28,
				"doc_count": 1
			}, {
				"key": 32,
				"doc_count": 1
			}]
		}
	}
}

解析数据

private void parseSearchResponse(SearchResponse response){
        SearchHits hits = response.getHits();
        SearchHit[] searchHits = hits.getHits();
        for(SearchHit hit : searchHits){
            String sourceAsString = hit.getSourceAsString();
            Account account = JSON.parseObject(sourceAsString, Account.class);
            System.out.println(account);
        }
        Aggregations aggregations = response.getAggregations();
        Terms agg1 = aggregations.get("agg1");
        for(Terms.Bucket bucket:agg1.getBuckets()){
            String keyAsString = bucket.getKeyAsString();
            System.out.println("年龄："+keyAsString);
        }
        Avg agg2 = aggregations.get("agg2");
        System.out.println("平均薪资："+agg2.getValue());
    }