记录一下elasticsearch的基础用法，高级用法后续再说。
话不多说，开始。
1、springboot 版本

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.6.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

注：为了spring boot和elasticsearch兼容，这里使用1.5.6
2、elasticsearch 版本：2.4.5
2.1、官网下载elasticsearch对应版本，解压，进入bin文件夹，执行 sh elasticsearch命令启动elasticsearch，可以看到两个地址

image.png

如图所示：9300端口下文将会在application.yml中用到，9200端口可以在浏览器或命令行中用到，是elasticsearch提供的rest接口。
2.2、下载elasticsearch-head，解压，进入目录，执行npm start，可以在浏览器中查看elasticsearch保存的数据，在启动前需要在elasticsearch.yml中配置两句话来解决跨域问题。

# allow origin
http.cors.enabled: true
http.cors.allow-origin: "*"

执行npm start启动elasticsearch-head插件，可以看见

image.png

3、pom.xml

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </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>net.java.dev.jna</groupId>
        <artifactId>jna</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

4、配置application.yml

spring:
  data:
    elasticsearch:
      clusterName: spring-boot
#    此处为elasticsearch提供的java接口
      cluster-nodes: 127.0.0.1:9300
      properties:
        path:
#        配置工程与外部elasticsearch链接
          home: /Users/CrazyMouse/Desktop/open-source/elasticsearch-2.4.5
#          logs: ./elasticsearch/log
#          data: ./elasticsearch/data

5、创建3个POJO
5.1、Article.java

//指定Article的索引和类型，相当于关系型数据库中的DB和TABLE
@Document(indexName = "project-name", type = "article")
public class Article implements Serializable {
    private Long id;
    private String title;
    private String abstracts;
    private String content;
    private Date postTime;
    private Long clickCount;
    private Author author;
    private Tutorial tutorial;

    //getter...
    //setter...
    //toString...

5.2、Author.java

public class Author implements Serializable {
    private Long id;
    private String name;
    private String remark;

    //getter...
    //setter...
    //toString...

5.3、Tutorial.java

public class Tutorial implements Serializable {
    private Long id;
    private String name;

    //getter...
    //setter...
    //toString...

6、创建Repository，只需集成ElasticsearchRepository即可

@Repository
public interface ArticleRepository extends ElasticsearchRepository<Article, Long> {
}

7、测试

@RestController
public class ArticleController {

    @Autowired
    private ArticleRepository articleRepository;

    @GetMapping("/article/{id}")
    public Article getArticle(@PathVariable Long id) {
        return articleRepository.findOne(id);
    }

    @GetMapping("/article")
    public List<Article> getArticles(@RequestParam String author_name) {
        QueryStringQueryBuilder builder = new QueryStringQueryBuilder(author_name);
        Iterable<Article> result = articleRepository.search(builder);
        Iterator<Article> it = result.iterator();
        List<Article> data = new LinkedList<>();
        while (it.hasNext()) {
            data.add(it.next());
        }
        return data;
    }

    @PostMapping("/article")
    public Article saveArticle(@RequestBody Article article) {
        article.setPostTime(new Date());
        articleRepository.save(article);
        return article;
    }

    @DeleteMapping("/article/{id}")
    public int deleteArticle(@PathVariable Long id) {
        articleRepository.delete(id);
        return 1;
    }
}

测试结果可以在elasticsearch-head插件中查看。