Spring Boot & ES 实战，值得参考！
作者：废物大师兄
cnblogs.com/cjsblog/p/9756978.html
1. 前言
1.1. 集成方式
Spring Boot中集成Elasticsearch有4种方式：
REST Client
Jest
Spring Data
Spring Data Elasticsearch Repositories
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
cluster.name: my-application
network.host: 192.168.1.134
http.port: 9200
network.host: 192.168.1.134
http.port: 9200
/etc/security/limits.conf
cheng soft nofile 65536
cheng hard nofile 65536
cheng hard nofile 65536
/etc/sysctl.conf
vm.max_map_count=262144
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
java.lang.NoClassDefFoundError: org/elasticsearch/common/transport/InetSocketTransportAddress
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>${spring.data.elasticsearch.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.cjs.example</groupId>
<artifactId>cjs-elasticsearch-example</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>cjs-elasticsearch-example</name>
<description></description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.5.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<elasticsearch.version>6.4.1</elasticsearch.version>
<spring.data.elasticsearch.version>3.1.0.RELEASE</spring.data.elasticsearch.version>
</properties>
<dependencies>
<dependency>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
<version>${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
spring.data.elasticsearch.cluster-name=my-application
spring.data.elasticsearch.cluster-nodes=192.168.1.134:9300
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
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;
@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;
}
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> {
}
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);
}
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);
}
}
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());
}
}
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
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;
@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);
}
}
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
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
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