Elasticsearch集成

1、Spring Data框架集成

1.1、Spring Data 框架介绍

Spring Data 是一个用于简化数据库、非关系型数据库、索引库访问，并支持云服务的开源框架。其主要目标是使得对数据的访问变得方便快捷，并支持 map-reduce 框架和云计算数据服务。 Spring Data 可以极大的简化 JPA（Elasticsearch„）的写法，可以在几乎不用写实现的情况下，实现对数据的访问和操作。除了 CRUD 外，还包括如分页、排序等一些常用的功能。
Spring Data 的官网：https://spring.io/projects/spring-data

Spring Data 常用的功能模块如下：

Spring Data JDBC
Spring Data Redis
Spring Data Elasticsearch
Spring Data Apache Hadoop

1.2、Spring Data Elasticsearch介绍

Spring Data Elasticsearch 基于 spring data API 简化 Elasticsearch 操作，将原始操作Elasticsearch 的客户端 API 进行封装。Spring Data 为 Elasticsearch 项目提供集成搜索引擎。Spring Data Elasticsearch POJO 的关键功能区域为中心的模型与 Elastichsearch 交互文档和轻松地编写一个存储索引库数据访问层。
官方网站：https://spring.io/projects/spring-data-elasticsearch

1.3、Spring Data Elasticsearch版本对比

1.4、框架集成

1.4.1、创建springboot项目

1.4.2、修改pom.xml文件

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.3.6.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.deepsea</groupId><artifactId>spring-es</artifactId><version>0.0.1-SNAPSHOT</version><name>SpringEsDemo</name><description>SpringEsDemo</description><properties><java.version>1.8</java.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-elasticsearch</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><configuration><excludes><exclude><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></exclude></excludes></configuration></plugin></plugins></build></project>

1.4.3、修改配置文件`application.yml`

logging:level:com.deepsea.es.spring: debug
#es服务连接
elasticsearch:host: localhostport: 9200

1.4.4、数据实体类

package com.deepsea.es.spring.model;import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.elasticsearch.annotations.Field;
import org.springframework.data.elasticsearch.annotations.FieldType;@Data
@NoArgsConstructor
@AllArgsConstructor
@Document(indexName = "shopping", shards = 3, replicas = 1)
public class Product {// 必须有ID，这里的id是全局唯一的标识，等同于es中的“_id"@Idprivate Long id;//商品唯一标识/*** type : 字段数据类型* analyzer : 分词器类型* index : 是否索引(默认:true)* Keyword : 短语,不进行分词*/@Field(type = FieldType.Text, analyzer = "ik_max_word")private String title;//商品名称@Field(type = FieldType.Keyword)private String category;//分类名称@Field(type = FieldType.Double)private Double price;//商品价格@Field(type = FieldType.Keyword, index = false)private String images;//图片地址
}

1.4.5、配置类

ElasticsearchRestTemplate 是 spring-data-elasticsearch 项目中的一个类，和其他 spring 项目中的 template类似。
在新版的 spring-data-elasticsearch 中，ElasticsearchRestTemplate 代替了原来的ElasticsearchTemplate。
原因是 ElasticsearchTemplate 基于 TransportClient，TransportClient 即将在 8.x 以后的版本中移除。所以，我们推荐使用 ElasticsearchRestTemplate。
ElasticsearchRestTemplate 基于 RestHighLevelClient 客户端的。需要自定义配置类，继承AbstractElasticsearchConfiguration，并实现 elasticsearchClient()抽象方法，创建 RestHighLevelClient 对象。

package com.deepsea.es.spring.config;import lombok.Data;
import lombok.Getter;
import lombok.Setter;
import org.apache.http.HttpHost;
import org.elasticsearch.client.RestClient;
import org.elasticsearch.client.RestClientBuilder;
import org.elasticsearch.client.RestHighLevelClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.elasticsearch.config.AbstractElasticsearchConfiguration;@Configuration
public class ElasticsearchConfig extends AbstractElasticsearchConfiguration {@Value("${elasticsearch.host}")private String host;@Value("${elasticsearch.port}")private Integer port;@Overridepublic RestHighLevelClient elasticsearchClient() {RestClientBuilder builder = RestClient.builder(new HttpHost(host, port));return new RestHighLevelClient(builder);}
}

1.4.6、DAO数据访问对象

package com.deepsea.es.spring.dao;import com.deepsea.es.spring.model.Product;
import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;
import org.springframework.stereotype.Repository;@Repository
public interface ProductDao extends ElasticsearchRepository<Product, Long> {}

1.4.7、索引操作

package com.deepsea.es.spring;import com.deepsea.es.spring.model.Product;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.elasticsearch.core.ElasticsearchRestTemplate;@SpringBootTest
class IndexTests {//注入 ElasticsearchRestTemplate@Autowiredprivate ElasticsearchRestTemplate elasticsearchRestTemplate;//创建索引并增加映射配置@Testpublic void createIndex() {//创建索引，系统初始化会根据实体类自动创建索引System.out.println("创建索引");}@Testpublic void deleteIndex(){boolean flg = elasticsearchRestTemplate.deleteIndex(Product.class);System.out.println("删除索引 = " + flg);}}

1.4.8、文档操作

package com.deepsea.es.spring;import com.deepsea.es.spring.dao.ProductDao;
import com.deepsea.es.spring.model.Product;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.TermQueryBuilder;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Sort;import java.util.ArrayList;
import java.util.List;@SpringBootTest
public class DocTests {@Autowiredprivate ProductDao productDao;/*** 新增*/@Testpublic void save() {Product product = new Product();product.setId(2L);product.setTitle("华为手机");product.setCategory("手机");product.setPrice(2999.0);product.setImages("http://www.atguigu/hw.jpg");productDao.save(product);}//修改@Testpublic void update() {Product product = new Product();product.setId(1L);product.setTitle("小米 2 手机");product.setCategory("手机");product.setPrice(9999.0);product.setImages("http://www.atguigu/xm.jpg");productDao.save(product);}//根据 id 查询@Testpublic void findById() {Product product = productDao.findById(1L).get();System.out.println(product);}//查询所有@Testpublic void findAll() {Iterable<Product> products = productDao.findAll();for (Product product : products) {System.out.println(product);}}//删除@Testpublic void delete() {Product product = new Product();product.setId(1L);productDao.delete(product);}//批量新增@Testpublic void saveAll() {List<Product> productList = new ArrayList<>();for (int i = 0; i < 10; i++) {Product product = new Product();product.setId(Long.valueOf(i));product.setTitle("[" + i + "]小米手机");product.setCategory("手机");product.setPrice(1999.0 + i);product.setImages("http://www.atguigu/xm.jpg");productList.add(product);}productDao.saveAll(productList);}//分页查询@Testpublic void findByPageable() {//设置排序(排序方式，正序还是倒序，排序的 id)Sort sort = Sort.by(Sort.Direction.DESC, "id");int currentPage = 0;//当前页，第一页从 0 开始，1 表示第二页int pageSize = 5;//每页显示多少条//设置查询分页PageRequest pageRequest = PageRequest.of(currentPage, pageSize, sort);//分页查询Page<Product> productPage = productDao.findAll(pageRequest);for (Product Product : productPage.getContent()) {System.out.println(Product);}}/*** term 查询* search(termQueryBuilder) 调用搜索方法，参数查询构建器对象*/@Testpublic void termQuery() {TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("title", "小米");Iterable<Product> products = productDao.search(termQueryBuilder);for (Product product : products) {System.out.println(product);}}/*** term 查询加分页*/@Testpublic void termQueryByPage() {int currentPage = 0;int pageSize = 5;//设置查询分页PageRequest pageRequest = PageRequest.of(currentPage, pageSize);TermQueryBuilder termQueryBuilder = QueryBuilders.termQuery("title", "小米");Iterable<Product> products = productDao.search(termQueryBuilder, pageRequest);for (Product product : products) {System.out.println(product);}}}