全文检索 — ElasticSearch_03（SpringDataElasticSearch快速入门、elasticsearchTemplate、articleRepository_CRUD）

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SpringDataElasticSearch快速入门

• 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库数据访问层。

• Spring Data ElasticSearch官方文档

1 SDES入门

1.2 导入坐标

<dependencies>
    <!--es-->
    <dependency>
        <groupId>org.elasticsearch</groupId>
        <artifactId>elasticsearch</artifactId>
        <version>5.6.8</version>
    </dependency>
    <dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>transport</artifactId>
        <version>5.6.8</version>
    </dependency>
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-to-slf4j</artifactId>
        <version>2.9.1</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.24</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-simple</artifactId>
        <version>1.7.21</version>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.12</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
    </dependency>


    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.8.1</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.8.1</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.8.1</version>
    </dependency>

	<!--springdata-->
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-elasticsearch</artifactId>
        <version>3.0.5.RELEASE</version>
        <exclusions>
            <exclusion>
                <groupId>org.elasticsearch.plugin</groupId>
                <artifactId>transport-netty4-client</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>5.0.4.RELEASE</version>
    </dependency>

</dependencies>

1.2 创建applicationContext.xml

• 引入elasticsearch命名空间

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:elasticsearch="http://www.springframework.org/schema/data/elasticsearch"
       xsi:schemaLocation="
		http://www.springframework.org/schema/beans
		http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context
		http://www.springframework.org/schema/context/spring-context.xsd
		http://www.springframework.org/schema/data/elasticsearch
		http://www.springframework.org/schema/data/elasticsearch/spring-elasticsearch-1.0.xsd
		">
    <!-- 扫描Dao(repositories)包，自动创建实例 -->
    <elasticsearch:repositories base-package="com.ruki.es.repositories" />

    <!-- 扫描Service包，创建Service的实体，可以没有，有repositories就够了 -->
    <context:component-scan base-package="com.ruki.es.service"/>

    <elasticsearch:transport-client id="esClient" cluster-name="my-elasticsearch"
        cluster-nodes="127.0.0.1:9300,127.0.0.1:9301,127.0.0.1:9302"/>

    <bean id="elasticsearchTemplate" class="org.springframework.data.elasticsearch.core.ElasticsearchTemplate">
        <constructor-arg name="client" ref="esClient" />
    </bean>
</beans>

1.3 编写配置实体类

• Article

@Document(indexName = "sdes_blog", type = "article")
public class Article {
    @Id
    @Field(type = FieldType.Long, store = true)
    private long id;
    @Field(type = FieldType.text, store = true, analyzer = "ik_smart")
    private String title;
    @Field(type = FieldType.text, store = true, analyzer = "ik_smart")
    private String content;

    //getter setter

    @Override
    public String toString() {
        return "Article{" +
                "id=" + id +
                ", title='" + title + '\'' +
                ", content='" + content + '\'' +
                '}';
    }
}

1. @Document(indexName="blob3",type="article")：

   1. indexName：索引的名称（必填项）
   2. type：索引的类型

2. @Id：主键的唯一标识

3. @Field(index=true,analyzer="ik_smart",store=true,searchAnalyzer="ik_smart",type = FieldType.text)

   1. index：是否设置分词
   2. analyzer：存储时使用的分词器
   3. searchAnalyze：搜索时使用的分词器
   4. store：是否存储
   5. type: 数据类型

1.4 编写Dao

• ArticleRepository
• 需要继承ElasticsearchRepository<T, ID>，<实体泛型,ID类型>

package com.ruki.es.repositories;

import com.ruki.es.entity.Article;
import org.springframework.data.domain.Pageable;
import org.springframework.data.elasticsearch.repository.ElasticsearchRepository;


import java.util.List;

public interface ArticleRepository extends ElasticsearchRepository<Article, Long> {
    public List<Article> findByTitle(String title);
    public List<Article> findByTitleOrContent(String title, String content);
    public List<Article> findByTitleOrContent(String title, String content, Pageable pageable);
}

1.5 编写service（可以不编写）

• 由于在applicationContext.xml中设置了<elasticsearch:repositories base-package="com.ruki.es.repositories" />，可以不编写service，直接使用articleRepository进行常规CRUD操作，也可以遵循方法命名规则，自定义方法进行操作。

public interface ArticleService {

    public void save(Article article);
    
}

@Service
public class ArticleServiceImpl implements ArticleService {

    @Autowired
    private ArticleRepository articleRepository;

    public void save(Article article) {
        articleRepository.save(article);
    }

}

1.6 创建测试类

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:applicationContext.xml")
public class SpringDataESTest {

    @Autowired
    private ArticleRepository articleRepository;

    @Autowired
    private ElasticsearchTemplate elasticsearchTemplate;
    
    //1. elasticsearchTemplate
    //1.1 创建索引
    //1.2 配置映射关系
    
    //2. articleRepository
    //2.1 添加文档
    //2.2 删除文档
    //2.3 查询全部
    //2.4 根据id查询
    //2.5 自定义方法查询
}

1.6.1 elasticsearchTemplate

1.6.1.1 创建索引/配置映射关系

@Test
public void testCreateIndex() {
    //创建索引，并配置映射关系
    elasticsearchTemplate.createIndex(Article.class);
    // 配置映射关系
    elasticsearchTemplate.putMapping(Article.class);
}

1.6.2 articleRepository

ArticleRepository的父类

@NoRepositoryBean
public interface CrudRepository<T, ID> extends Repository<T, ID> {
    <S extends T> S save(S var1);

    <S extends T> Iterable<S> saveAll(Iterable<S> var1);

    Optional<T> findById(ID var1);

    boolean existsById(ID var1);

    Iterable<T> findAll();

    Iterable<T> findAllById(Iterable<ID> var1);

    long count();

    void deleteById(ID var1);

    void delete(T var1);

    void deleteAll(Iterable<? extends T> var1);

    void deleteAll();
}

自定义查询规则

关键字	命名规则	解释	示例
and	findByField1AndField2	根据Field1和Field2获得数据	findByTitleAndContent
or	findByField1OrField2	根据Field1或Field2获得数据	findByTitleOrContent
is	findByField	根据Field获得数据	findByTitle
not	findByFieldNot	根据Field获得补集数据	findByTitleNot
between	findByFieldBetween	获得指定范围的数据	findByPriceBetween
lessThanEqual	findByFieldLessThan	获得小于等于指定值的数据	findByPriceLessThan

1.6.2.1 添加文档 save

@Test
public void addDocument() {
    for (int i = 3; i < 10; i++) {
        Article article = new Article();
        article.setId(i);
        article.setTitle(i + "Maven项目对象模型(POM)");
        article.setContent(i + "可以通过一小段描述信息来管理项目的构建，报告和文档的项目管理工具软件。Maven 除了以程序构建能力为特色之外，还提供高级项目管理工具。");
        articleRepository.save(article);
    }
}

1.6.2.2 删除文档 deleteById

@Test
public void deleteDocument() {
	articleRepository.deleteById(2l);
}

1.6.2.3 查询全部 findAll

@Test
public void findAll() {
    Iterable<Article> articles = articleRepository.findAll();
    articles.forEach(a -> System.out.println(a));
}

1.6.2.4 根据id查询 findById

@Test
public void findById() {
    Optional<Article> optional = articleRepository.findById(3l);
    if (optional != null) {
        Article article = optional.get();
        System.out.println(article);
    }
}

1.6.2.5 自定义方法查询 findByTitle

//自定义方法查询
@Test
public void testFindByTitle() {
    List<Article> list = articleRepository.findByTitle("项目");
    list.stream().forEach(a -> System.out.println(a));
}

@Test
public void testFindByTitleOrContent() {
    //没有分页查询
    //        List<Article> list = articleRepository.findByTitleOrContent("项目", "构建");
    //分页查询
    Pageable pageable = PageRequest.of(0,5);
    List<Article> list = articleRepository.findByTitleOrContent("项目", "构建", pageable);
    list.stream().forEach(a -> System.out.println(a));
}

1.6.2.6 使用原生查询对象进行查询

@Test
public void testNativeSearchQuery() {
    NativeSearchQuery nativeSearchQuery = new NativeSearchQueryBuilder()
        .withQuery(QueryBuilders.queryStringQuery("maven是一个构建工具").defaultField("title"))//设置查询条件
        .withPageable(PageRequest.of(0, 5))//设置分页
        .build();//构建查询对象
    List<Article> articles = elasticsearchTemplate.queryForList(nativeSearchQuery, Article.class);
    articles.stream().forEach(a -> System.out.println(a));
}