Spring Boot中集成Elasticsearch有4种方式：

本文用后面两种方式来分别连接并操作Elasticsearch

服务端：elasticsearch-6.3.2 1台

客户端：elasticsearch 6.4.1

服务端配置文件：elasticsearch.yml

cluster .name:  my-application network .host: 192 .168.1.134 http .port: 9200

/etc/security/limits.conf

cheng soft nofile  65536 cheng hard nofile  65536

/etc/sysctl.conf

vm.max_map_count=262144

Spring Boot 2.0.5默认的elasticsearch版本很低，这里我们用最新版本6.4.1

如果启动过程中出现

则说明，elasticsearch依赖的jar包版本不一致，统一改成6.4.1即可

另外，Spring Boot 2.0.5依赖的spring-data-elasticsearch版本是3.0.1，需要升级到3.1.0

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">      <modelVersion>4.0.0 </modelVersion>      <groupId>com.cjs.example </groupId>      <artifactId>cjs-elasticsearch-example </artifactId>      <version>0.0.1-SNAPSHOT </version>      <packaging>jar </packaging>      <name>cjs-elasticsearch-example </name>      <description></description>      <parent>          <groupId>org.springframework.boot </groupId>          <artifactId>spring-boot-starter-parent </artifactId>          <version>2.0.5.RELEASE </version>          <relativePath/>  <!-- lookup parent from repository -->      </parent>      <properties>          <project.build.sourceEncoding>UTF-8 </project.build.sourceEncoding>          <project.reporting.outputEncoding>UTF-8 </project.reporting.outputEncoding>          <java.version>1.8 </java.version>          <elasticsearch.version>6.4.1 </elasticsearch.version>          <spring.data.elasticsearch.version>3.1.0.RELEASE </spring.data.elasticsearch.version>      </properties>      <dependencies>          <dependency>              <groupId>org.elasticsearch </groupId>              <artifactId>elasticsearch </artifactId>              <version>${elasticsearch.version} </version>          </dependency>          <dependency>              <groupId>org.elasticsearch.client </groupId>              <artifactId>transport </artifactId>              <version>${elasticsearch.version} </version>          </dependency>          <dependency>              <groupId>org.elasticsearch.client </groupId>              <artifactId>elasticsearch-rest-client </artifactId>              <version>${elasticsearch.version} </version>          </dependency>          <dependency>              <groupId>org.elasticsearch.plugin </groupId>              <artifactId>transport-netty4-client </artifactId>              <version>${elasticsearch.version} </version>          </dependency>          <dependency>              <groupId>org.springframework.data </groupId>              <artifactId>spring-data-elasticsearch </artifactId>              <version>${spring.data.elasticsearch.version} </version>          </dependency>          <dependency>              <groupId>org.springframework.boot </groupId>              <artifactId>spring-boot-starter-data-elasticsearch </artifactId>          </dependency>          <dependency>              <groupId>org.springframework.boot </groupId>              <artifactId>spring-boot-starter-web </artifactId>          </dependency>          <dependency>              <groupId>org.projectlombok </groupId>              <artifactId>lombok </artifactId>              <optional>true </optional>          </dependency>          <dependency>              <groupId>org.springframework.boot </groupId>              <artifactId>spring-boot-starter-test </artifactId>              <scope>test </scope>          </dependency>      </dependencies>      <build>          <plugins>              <plugin>                  <groupId>org.springframework.boot </groupId>                  <artifactId>spring-boot-maven-plugin </artifactId>              </plugin>          </plugins>      </build> </project>

spring. data.elasticsearch.cluster-name=my-application spring. data.elasticsearch.cluster-nodes= 192.168.1.134: 9300

也许，大家会疑惑，配置文件中明明写的端口是9200，为何这里配置文件中连接的时候写的端口是9300呢？

因为，配置9200是通过HTTP连接的端口，9300是TCP连接的端口

首先，定义一个实体类

package com.cjs.example.entity; import lombok.Data; import org.springframework. data. annotation.Id; import org.springframework. data.elasticsearch.annotations.Document; import java.io.Serializable; @Data @Document(indexName = "commodity") public  class Commodity implements Serializable {      @Id      private String skuId;      private String name;      private String category;      private Integer price;      private String brand;      private Integer stock; }

这里定义了Commodity实例，表示商品。在Elasticsearch 6.X 版本中，不建议使用type，而且在7.X版本中将会彻底废弃type，所以此处我只指定了indexName，没有指定type。

这里，一个Commodity代表一个商品，同时代表一条索引记录。

类比关系型数据库的话，Index相当于表，Document相当于记录，然后，需要自己定义一个接口，并继承ElasticsearchRepository。

package  com .cjs.example.dao; import  com .cjs.example.entity.Commodity; import  org .springframework.data.elasticsearch.repository.ElasticsearchRepository; import  org .springframework.stereotype.Repository; @ Repository public interface CommodityRepository extends ElasticsearchRepository<Commodity, String> { }

这里的Repository相当于DAO，操作mysql还是elasticsearch都是一样的

接下来，定义service接口

package com.cjs.example.service; import com.cjs.example.entity.Commodity; import org.springframework.data.domain.Page; import java.util.List; public  interface CommodityService {      long count();      Commodity save(Commodity commodity);      void delete(Commodity commodity);      Iterable<Commodity> getAll();      List<Commodity> getByName(String name);      Page<Commodity> pageQuery(Integer pageNo, Integer pageSize, String kw); }

实现类

package com.cjs.example.service.impl; import com.cjs.example.entity.Commodity; import com.cjs.example.dao.CommodityRepository; import com.cjs.example.service.CommodityService; import org.elasticsearch.index.query.MatchQueryBuilder; import org.elasticsearch.index.query.QueryBuilders; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.Page; import org.springframework.data.domain.PageRequest; import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder; import org.springframework.data.elasticsearch.core.query.SearchQuery; import org.springframework.stereotype.Service; import java.util.ArrayList; import java.util.List; @Service public  class CommodityServiceImpl implements CommodityService {      @Autowired      private CommodityRepository commodityRepository;      @Override      public long count() {          return commodityRepository.count();     }      @Override      public Commodity save(Commodity commodity) {          return commodityRepository.save(commodity);     }      @Override      public void delete(Commodity commodity) {         commodityRepository.delete(commodity); //        commodityRepository.deleteById(commodity.getSkuId());     }      @Override      public Iterable<Commodity> getAll() {          return commodityRepository.findAll();     }      @Override      public List<Commodity> getByName(String name) {         List<Commodity> list =  new ArrayList<>();         MatchQueryBuilder matchQueryBuilder =  new MatchQueryBuilder( "name", name);         Iterable<Commodity> iterable = commodityRepository.search(matchQueryBuilder);         iterable.forEach(e->list.add(e));          return list;     }      @Override      public Page<Commodity> pageQuery(Integer pageNo, Integer pageSize, String kw) {         SearchQuery searchQuery =  new NativeSearchQueryBuilder()                 .withQuery(QueryBuilders.matchPhraseQuery( "name", kw))                 .withPageable(PageRequest.of(pageNo, pageSize))                 .build();          return commodityRepository.search(searchQuery);     } }

在这个Service中演示了增删查改操作，还有分页查询

最后，写一个测试类测试其中的方法

package com.cjs.example; import com.cjs.example.entity.Commodity; import com.cjs.example.service.CommodityService; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.data.domain.Page; import org.springframework.test.context.junit4.SpringRunner; import java.util.List; @RunWith(SpringRunner.class) @SpringBootTest public  class CjsElasticsearchExampleApplicationTests {      @Autowired      private CommodityService commodityService;      @Test      public void contextLoads() {         System.out.println(commodityService.count());     }      @Test      public void testInsert() {         Commodity commodity =  new Commodity();         commodity.setSkuId( "1501009001");         commodity.setName( "原味切片面包（10片装）");         commodity.setCategory( "101");         commodity.setPrice( 880);         commodity.setBrand( "良品铺子");         commodityService.save(commodity);         commodity =  new Commodity();         commodity.setSkuId( "1501009002");         commodity.setName( "原味切片面包（6片装）");         commodity.setCategory( "101");         commodity.setPrice( 680);         commodity.setBrand( "良品铺子");         commodityService.save(commodity);         commodity =  new Commodity();         commodity.setSkuId( "1501009004");         commodity.setName( "元气吐司850g");         commodity.setCategory( "101");         commodity.setPrice( 120);         commodity.setBrand( "百草味");         commodityService.save(commodity);     }      @Test      public void testDelete() {         Commodity commodity =  new Commodity();         commodity.setSkuId( "1501009002");         commodityService.delete(commodity);     }      @Test      public void testGetAll() {         Iterable<Commodity> iterable = commodityService.getAll();         iterable.forEach(e->System.out.println(e.toString()));     }      @Test      public void testGetByName() {         List<Commodity> list = commodityService.getByName( "面包");         System.out.println(list);     }      @Test      public void testPage() {         Page<Commodity> page = commodityService.pageQuery( 0,  10,  "切片");         System.out.println(page.getTotalPages());         System.out.println(page.getNumber());         System.out.println(page.getContent());     } }

以上，便是使用Elasticsearch Repositories的方式

package com.cjs.example; import com.cjs.example.entity.Commodity; import org.elasticsearch.index.query.QueryBuilders; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.data.elasticsearch.core.ElasticsearchTemplate; import org.springframework.data.elasticsearch.core.query.*; import org.springframework.test.context.junit4.SpringRunner; import java.util.List; @RunWith(SpringRunner.class) @SpringBootTest public  class ElasticsearchTemplateTest {      @Autowired      public ElasticsearchTemplate elasticsearchTemplate;      @Test      public void testInsert() {         Commodity commodity =  new Commodity();         commodity.setSkuId( "1501009005");         commodity.setName( "葡萄吐司面包（10片装）");         commodity.setCategory( "101");         commodity.setPrice( 160);         commodity.setBrand( "良品铺子");         IndexQuery indexQuery =  new IndexQueryBuilder().withObject(commodity).build();         elasticsearchTemplate.index(indexQuery);     }      @Test      public void testQuery() {         SearchQuery searchQuery =  new NativeSearchQueryBuilder()                 .withQuery(QueryBuilders.matchQuery( "name",  "吐司"))                 .build();         List<Commodity> list = elasticsearchTemplate.queryForList(searchQuery, Commodity.class);         System.out.println(list);     } }

ElasticsearchTemplate是自动配置的