ElasticSearch回顾3-SpirngBoot整合ES

本篇我们熟悉一下ES在Java中的操作，并将ES整合在SpringBoot中

首先贴官网API地址

https://www.elastic.co/guide/cn/elasticsearch/guide/current/index.html

API创建索引及文档

去官网找一圈

https://www.elastic.co/guide/index.html

找到Elasticsearch Clients（这个就是客户端api文档）

这里我们用JavaRest风格的API，我们可以根据自己的语言环境来选择不同的API

选择Java后，我们又发现Java分了两种

一种是high level 和 low level，我们选择high level下的Getting started

找到Maven依赖和基本配置

关于Java Rest Client的说明

Java REST Client 有两种风格：

Java Low Level REST Client ：用于Elasticsearch的官方低级客户端。它允许通过http与Elasticsearch 集群通信。将请求编排和响应反编排留给用户自己处理。它兼容所有的Elasticsearch版本。（PS：学过 WebService的话，对编排与反编排这个概念应该不陌生。可以理解为对请求参数的封装，以及对响应结 果的解析）

Java High Level REST Client ：用于Elasticsearch的官方高级客户端。它是基于低级客户端的，它提供 很多API，并负责请求的编排与响应的反编排。（PS：就好比是，一个是传自己拼接好的字符串，并且 自己解析返回的结果；而另一个是传对象，返回的结果也已经封装好了，直接是对象，更加规范了参数 的名称以及格式，更加面对对象一点） （PS：所谓低级与高级，我觉得一个很形象的比喻是，面向过程编程与面向对象编程）

项目整合

新建项目

新建一个SpringBoot项目，导入web依赖和elastic依赖

如果忘了也没关系，在pom中加入即可

<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-elasticsearch</artifactId> </dependency>

因为SpringBoot默认的配置版本不匹配，我们要自己手动配置自己的ES版本

<elasticsearch.version>7.8.0</elasticsearch.version>

继续查看文档API，

我们发现这里要我们构建一个RestHighLevel的对象，那就整吧

创建配置类

ElasticsearchClientConfig.java

package com.feng.util; import org.apache.http.HttpHost; 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; /** * <h3>springboot-elasticsearch-test</h3> * <p></p> * * @author : Nicer_feng * @date : 2020-10-21 09:13 **/ @Configuration public class ElasticsearchClientConfig { @Bean public RestHighLevelClient restHighLevelClient(){ RestClientBuilder restClientBuilder; RestHighLevelClient client = new RestHighLevelClient( RestClient.builder( new HttpHost("127.0.0.1",9200,"http"))); return client; } }

ESUtil.java

package com.feng.util; import com.alibaba.fastjson.JSON; import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest; import org.elasticsearch.action.bulk.BulkRequest; import org.elasticsearch.action.bulk.BulkResponse; import org.elasticsearch.action.delete.DeleteRequest; import org.elasticsearch.action.delete.DeleteResponse; import org.elasticsearch.action.get.GetRequest; import org.elasticsearch.action.get.GetResponse; import org.elasticsearch.action.index.IndexRequest; import org.elasticsearch.action.index.IndexResponse; import org.elasticsearch.action.search.SearchRequest; import org.elasticsearch.action.search.SearchResponse; import org.elasticsearch.action.support.master.AcknowledgedResponse; import org.elasticsearch.action.update.UpdateRequest; import org.elasticsearch.action.update.UpdateResponse; import org.elasticsearch.client.RequestOptions; import org.elasticsearch.client.RestHighLevelClient; import org.elasticsearch.client.indices.GetIndexRequest; import org.elasticsearch.common.unit.TimeValue; import org.elasticsearch.common.xcontent.XContentType; import org.elasticsearch.index.query.QueryBuilders; import org.elasticsearch.rest.RestStatus; import org.elasticsearch.search.builder.SearchSourceBuilder; import org.elasticsearch.search.fetch.subphase.FetchSourceContext; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import java.io.IOException; import java.util.List; import java.util.concurrent.TimeUnit; /** * <h3>springboot-elasticsearch-test</h3> * <p></p> * * @author : Nicer_feng * @date : 2020-10-21 09:19 **/ public class ESUtils<T> { @Autowired @Qualifier("restHighLevelClient") private RestHighLevelClient client; /** * 判断索引是否存在 * @param index * @return * @throws IOException */ public boolean existsIndex(String index) throws IOException { GetIndexRequest request = new GetIndexRequest(index); boolean exists = client.indices().exists(request, RequestOptions.DEFAULT); return exists; } /** * 删除索引 * @param index * @return * @throws IOException */ public boolean deleteIndex(String index) throws IOException { DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest(index); AcknowledgedResponse response = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT); return response.isAcknowledged(); } /** * 判断某索引下文档id是否存在 * @param index * @param id * @return * @throws IOException */ public boolean docExists(String index, String id) throws IOException { GetRequest getRequest = new GetRequest(index,id); //只判断索引是否存在不需要获取_source getRequest.fetchSourceContext(new FetchSourceContext(false)); getRequest.storedFields("_none_"); boolean exists = client.exists(getRequest, RequestOptions.DEFAULT); return exists; } /** * 添加文档记录 * @param index * @param id * @param t 要添加的数据实体类 * @return * @throws IOException */ public boolean addDoc(String index,String id,T t) throws IOException { IndexRequest request = new IndexRequest(index); request.id(id); //timeout request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); request.source(JSON.toJSONString(t), XContentType.JSON); IndexResponse indexResponse = client.index(request, RequestOptions.DEFAULT); RestStatus Status = indexResponse.status(); return Status==RestStatus.OK||Status== RestStatus.CREATED; } /** * 根据id来获取记录 * @param index * @param id * @return * @throws IOException */ public GetResponse getDoc(String index, String id) throws IOException { GetRequest request = new GetRequest(index,id); GetResponse getResponse = client.get(request, RequestOptions.DEFAULT); return getResponse; } /** * 批量添加文档记录 * 没有设置id ES会自动生成一个，如果要设置 IndexRequest的对象.id()即可 * @param index * @param list * @return * @throws IOException */ public boolean bulkAdd(String index, List<T> list) throws IOException { BulkRequest bulkRequest = new BulkRequest(); //timeout bulkRequest.timeout(TimeValue.timeValueMinutes(2)); bulkRequest.timeout("2m"); for (int i =0;i<list.size();i++){ bulkRequest.add(new IndexRequest(index) .source(JSON.toJSONString(list.get(i)))); } BulkResponse bulkResponse = client.bulk(bulkRequest, RequestOptions.DEFAULT); return !bulkResponse.hasFailures(); } /** * 批量删除和更新就不写了可根据上面几个方法来写 */ /** * 更新文档记录 * @param index * @param id * @param t * @return * @throws IOException */ public boolean updateDoc(String index,String id,T t) throws IOException { UpdateRequest request = new UpdateRequest(index,id); request.doc(JSON.toJSONString(t)); request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); UpdateResponse updateResponse = client.update( request, RequestOptions.DEFAULT); return updateResponse.status()==RestStatus.OK; } /** * 删除文档记录 * @param index * @param id * @return * @throws IOException */ public boolean deleteDoc(String index,String id) throws IOException { DeleteRequest request = new DeleteRequest(index,id); //timeout request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); DeleteResponse deleteResponse = client.delete( request, RequestOptions.DEFAULT); return deleteResponse.status()== RestStatus.OK; } /** * 根据某字段来搜索 * @param index * @param field * @param key 要收搜的关键字 * @throws IOException */ public void search(String index,String field ,String key,Integer from,Integer size) throws IOException { SearchRequest searchRequest = new SearchRequest(index); SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); sourceBuilder.query(QueryBuilders.termQuery(field, key)); //控制搜素 sourceBuilder.from(from); sourceBuilder.size(size); //最大搜索时间。 sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS)); searchRequest.source(sourceBuilder); SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT); System.out.println(JSON.toJSONString(searchResponse.getHits())); } }

这里注意pom中导入alibaba的fastjson类

<dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.74</version> </dependency>

测试

然后我们测试创建索引

创建索引

package com.feng; import org.elasticsearch.client.RequestOptions; import org.elasticsearch.client.RestHighLevelClient; import org.elasticsearch.client.indices.CreateIndexRequest; import org.elasticsearch.client.indices.CreateIndexResponse; import org.junit.jupiter.api.Test; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import java.io.IOException; @SpringBootTest class SpringbootElasticsearchTestApplicationTests { @Autowired RestHighLevelClient restHighLevelClient; @Test void contextLoads() throws IOException { //1、索引创建 CreateIndexRequest request = new CreateIndexRequest("feng_index1"); //2、执行请求 ==> 请求后获取响应 CreateIndexResponse createIndexResponse = restHighLevelClient.indices().create(request, RequestOptions.DEFAULT); System.out.println(createIndexResponse); } }

成功运行并创建索引

获取索引

@Test void testExistsIndex() throws IOException { GetIndexRequest request = new GetIndexRequest("feng_index1"); boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT); System.out.println(exists); }

测试存在

删除索引

@Test void testDeleteIndexRequest() throws IOException { DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("feng_index1"); AcknowledgedResponse response = restHighLevelClient.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT); System.out.println(response.isAcknowledged()); }

测试，返回true，且刷新后 feng_index1消失

如果我们要添加文档记录呢？

添加文档

首先创建一个实体类

User.java

package com.feng.dao; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import org.springframework.stereotype.Component; /** * <h3>springboot-elasticsearch-test</h3> * <p></p> * * @author : Nicer_feng * @date : 2020-10-21 13:45 **/ @Data @AllArgsConstructor @NoArgsConstructor @Component public class User { private String name; private int age; }

lombok插件别再问了

测试类

@Test void testAddDocument() throws IOException { // 创建对象 User user = new User("冯半仙", 6); // 创建请求 IndexRequest request = new IndexRequest("feng_index1"); // 规则 request.id("1"); request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); request.source(JSON.toJSONString(user), XContentType.JSON); // 发送请求 IndexResponse indexResponse = restHighLevelClient.index(request, RequestOptions.DEFAULT); System.out.println(indexResponse.toString()); RestStatus Status = indexResponse.status(); System.out.println(Status == RestStatus.OK || Status == RestStatus.CREATED); }

运行成功发现

判断索引下文档id是否存在

// 判断此id是否存在这个索引库中 @Test void testIsExists() throws IOException { GetRequest getRequest = new GetRequest("feng_index1","1"); // 不获取_source上下文 storedFields getRequest.fetchSourceContext(new FetchSourceContext(false)); getRequest.storedFields("_none_"); // 判断此id是否存在！ boolean exists = restHighLevelClient.exists(getRequest, RequestOptions.DEFAULT); System.out.println(exists); }

查询1和2分别返回结果true和false

根据id查询记录

// 获得文档记录 @Test void testGetDocument() throws IOException { GetRequest getRequest = new GetRequest("feng_index1","1"); GetResponse getResponse = restHighLevelClient.get(getRequest, RequestOptions.DEFAULT); System.out.println(getResponse.getSourceAsString()); // 打印文档内容 System.out.println(getResponse); }

运行结果

更新文档记录

// 更新文档记录 @Test void testUpdateDocument() throws IOException { UpdateRequest request = new UpdateRequest("feng_index1","1"); request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); User user = new User("冯半仙996", 18); request.doc(JSON.toJSONString(user), XContentType.JSON); UpdateResponse updateResponse = restHighLevelClient.update( request, RequestOptions.DEFAULT); System.out.println(updateResponse.status() == RestStatus.OK); }

当然更新成功

删除文档记录

// 删除文档测试 @Test void testDelete() throws IOException { DeleteRequest request = new DeleteRequest("feng_index1","3"); //timeout request.timeout(TimeValue.timeValueSeconds(1)); request.timeout("1s"); DeleteResponse deleteResponse = restHighLevelClient.delete( request, RequestOptions.DEFAULT); System.out.println(deleteResponse.status() == RestStatus.OK); }

记得先插一个3，再删除哈

批量添加数据

// 批量添加数据 @Test void testBulkRequest() throws IOException { BulkRequest bulkRequest = new BulkRequest(); //timeout bulkRequest.timeout(TimeValue.timeValueMinutes(2)); bulkRequest.timeout("2m"); ArrayList<User> userList = new ArrayList<>(); userList.add(new User("feng1",3)); userList.add(new User("feng2",3)); userList.add(new User("feng3",3)); userList.add(new User("banxian1",3)); userList.add(new User("banxian2",3)); userList.add(new User("banxian3",3)); for (int i =0;i<userList.size();i++){ bulkRequest .add(new IndexRequest("feng_index1") .id(""+(i+1)) .source(JSON.toJSONString(userList.get(i)),XContentType.JSON)); } // bulk BulkResponse bulkResponse = restHighLevelClient.bulk(bulkRequest,RequestOptions.DEFAULT); System.out.println(!bulkResponse.hasFailures()); }

运行后发现数据成功插入

查询测试

// 查询测试 /** * 使用QueryBuilder * termQuery("key", obj) 完全匹配 * termsQuery("key", obj1, obj2..) 一次匹配多个值 * matchQuery("key", Obj) 单个匹配, field不支持通配符, 前缀具高级特性 * multiMatchQuery("text", "field1", "field2"..); 匹配多个字段, field有通 配符忒行 * matchAllQuery(); 匹配所有文件 */ @Test void testSearch() throws IOException { SearchRequest searchRequest = new SearchRequest("feng_index1"); SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); // TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("name","qinjiang1"); MatchAllQueryBuilder matchAllQueryBuilder = QueryBuilders.matchAllQuery(); sourceBuilder.query(matchAllQueryBuilder); sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS)); searchRequest.source(sourceBuilder); SearchResponse response = restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT); System.out.println(JSON.toJSONString(response.getHits())); System.out.println("================SearchHit=================="); for (SearchHit documentFields : response.getHits().getHits()) { System.out.println(documentFields.getSourceAsMap()); } }

运行后