SpringBoot+Elasticsearch

Posted 2021-01-11

1. 前言
   1.1. 集成方式
   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
   1.2. 环境与配置
   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
   /etc/security/limits.conf
   /etc/sysctl.conf
   1.3. 版本
   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
   
2. 依赖
   <?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>
3. application.properties
   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
   
4. 操作
   4.1. 使用Spring Data Elasticsearch Repositories操作Elasticsearch
   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;br/>@Data
   @Document(indexName = "commodity")
   public class Commodity implements Serializable {br/>@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;br/>@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;br/>@Service
   public class CommodityServiceImpl implements CommodityService {br/>@Autowired
   private CommodityRepository commodityRepository;br/>@Override
   public long count() {
   return commodityRepository.count();br/>@Override
   public Commodity save(Commodity commodity) {
   return commodityRepository.save(commodity);br/>@Override
   public void delete(Commodity commodity) {
   commodityRepository.delete(commodity);
   // commodityRepository.deleteById(commodity.getSkuId());br/>@Override
   public Iterable<Commodity> getAll() {
   return commodityRepository.findAll();br/>@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;br/>@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;br/>@RunWith(SpringRunner.class)
   @SpringBootTest
   public class CjsElasticsearchExampleApplicationTests {br/>@Autowired
   private CommodityService commodityService;br/>@Test
   public void contextLoads() {br/>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.setName("元气吐司850g");
   commodity.setCategory("101");
   commodity.setPrice(120);
   commodity.setBrand("百草味");
   commodityService.save(commodity);
   @Test
   br/>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();commodityService.delete(commodity);
   @Test
   br/>commodity.setSkuId("1501009002");
   commodityService.delete(commodity);
   @Test
   public void testGetAll() {
   Iterable<Commodity> iterable = commodityService.getAll();br/>iterable.forEach(e->System.out.println(e.toString()));
   @Test
   public void testGetByName() {
   List<Commodity> list = commodityService.getByName("面包");br/>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
   4.2. 使用ElasticsearchTemplate方式操作Elasticsearch
   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;br/>@RunWith(SpringRunner.class)
   @SpringBootTest
   public class ElasticsearchTemplateTest {br/>@Autowired
   public ElasticsearchTemplate elasticsearchTemplate;br/>@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();br/>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
   
5. 演示
   
6. 工程结构
   
7. 参考
   https://docs.spring.io/spring-data/elasticsearch/docs/3.1.0.RELEASE/reference/html/#repositories.query-methods.details