Spring Boot整合Elasticsearch全文搜索引擎

这一篇介绍Spring Boot整合Elasticsearch全文搜索引擎，需要springboot实战完整视频教程的，点击这里！

Elastic Search是一个开源的，分布式，实时搜索和分析引擎。Spring Boot为Elasticsearch及Spring Data Elasticsearch提供的基于它的抽象提供了基本的配置。Spring Boot提供了一个用于聚集依赖的spring-boot-starter-data-elasticsearch 'StarterPOM'。

引入spring-boot-starter-data-elasticsearch依赖，在pom.xml配置文件中增加如下内容（基于之前章节“Spring Boot 构建框架”中的pom.xml文件）：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>

可以像其他Spring beans那样注入一个自动配置的ElasticsearchTemplate或Elasticsearch客户端实例。默认情况下，该实例将尝试连接到一个本地内存服务器（在Elasticsearch项目中的一个NodeClient），但可以通过设置spring.data.elasticsearch.clusterNodes为一个以逗号分割的host:port列表来将其切换到一个远程服务器（比如，TransportClient）。

@Component
public class MyBean {
    private ElasticsearchTemplate template;
    
    @Autowired
    public MyBean(ElasticsearchTemplate template) {
        this.template = template;
    }
    // ...
}

如果添加一个自己的ElasticsearchTemplate类型的@Bean，它将替换默认的。

应用集成ElasticSearch案例
新建elasticsearch.properties配置文件，添加如下配置内容：

elasticsearch.host=localhost
elasticsearch.port=9300

ElasticSearch配置，读取elasticsearch.properties配置文件信息，具体代码如下：

@Configuration@PropertySource(value = "classpath:elasticsearch.properties")
@EnableElasticsearchRepositories(basePackages = "co.paan.repository")
public class ElasticsearchConfiguration {
    @Resource
private Environment environment;
@Bean
public Client client() {
TransportClient client = new TransportClient();
TransportAddress address = new InetSocketTransportAddress(environment.getProperty("elasticsearch.host"), Integer.parseInt(environment.getProperty("elasticsearch.port")));
client.addTransportAddress(address);        
return client;
}
    @Beanpublic ElasticsearchOperations elasticsearchTemplate() {
        return new ElasticsearchTemplate(client());
    }
}

两个实体类，具体代码如下：

@Document(indexName = "post", type = "post", shards = 1, replicas = 0)
public class Post {
@Id
private String id;
    private String title;
@Field(type= FieldType.Nested)
private List<Tag> tags;   
 public String getId() {
return id;
}
    public void setId(String id) {
        this.id = id;
}
    public String getTitle() {
        return title;
}
    public void setTitle(String title) {
        this.title = title;
}
    public List<Tag> getTags() {
        return tags;
}
    public void setTags(List<Tag> tags) {
        this.tags = tags;
}
}
public class Tag {
private String id;   
private String name;   
public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

数据源继承ElasticsearchRepository类，封装接口代码如下：

public interface PostRepository extends ElasticsearchRepository<Post, String>{
    Page<Post> findByTagsName(String name, Pageable pageable);
}

数据服务接口及实现类，代码如下：

public interface PostService {
    Post save(Post post);
    Post findOne(String id);
    Iterable<Post> findAll();
    Page<Post> findByTagsName(String tagName, PageRequest pageRequest);
}
@Servicepublic class PostServiceImpl implements PostService{
    @Autowired
private PostRepository postRepository;
@Override
public Post save(Post post) {
        postRepository.save(post);        
              return post;
       }
    @Overridepublic Post findOne(String id) {
        return postRepository.findOne(id);
   }
    @Overridepublic Iterable<Post> findAll() {
        return postRepository.findAll();
   }
    @Overridepublic Page<Post> findByTagsName(String tagName, PageRequest pageRequest) {
        return postRepository.findByTagsName(tagName, pageRequest);
   }
}

测试代码如下：

@Test
public void testFindByTagsName() throws Exception {
    Tag tag = new Tag();
    tag.setId("1");
    tag.setName("tech");
    Tag tag2 = new Tag();
    tag2.setId("2");
    tag2.setName("elasticsearch");
    Post post = new Post();
    post.setId("1");
    post.setTitle("Bigining with spring boot application and elasticsearch");
    post.setTags(Arrays.asList(tag, tag2));
    postService.save(post);
    Post post2 = new Post();
    post2.setId("1");
    post2.setTitle("Bigining with spring boot application");
    post2.setTags(Arrays.asList(tag));
    postService.save(post);
    Page<Post> posts  = postService.findByTagsName("tech", new PageRequest(0,10));
    Page<Post> posts2  = postService.findByTagsName("tech", new PageRequest(0,10));
    Page<Post> posts3  = postService.findByTagsName("maz", new PageRequest(0,10));
    assertThat(posts.getTotalElements(), is(1L));
    assertThat(posts2.getTotalElements(), is(1L));
    assertThat(posts3.getTotalElements(), is(0L));
}

链接来源：https://blog.yoodb.com/yoodb/article/detail/1412