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目录

Elasticsearch编程

一、环境准备

1、准备IDEA项目结构

2、准备POM依赖

3、创建用于保存职位信息的实体类

4、编写接口和实现类

5、创建实现类

Elasticsearch编程

要将搜索的功能与前端对接，我们必须要使用Java代码来实现对Elasticsearch的操作。我们要使用一个JobService类来实现之前我们用RESTFul完成的操作

一、环境准备

1、准备IDEA项目结构

  • 创建elasticsearch_example项目
  • 创建包结构如下所示

包

说明

cn.it.elasticsearch.entity

存放实体类

cn.it.elasticsearch.service

存放服务接口

cn.it.elasticsearch.service.impl

存放服务接口实现类

2、准备POM依赖

<repositories><!-- 代码库 --><repository><id>aliyun</id><url>http://maven.aliyun.com/nexus/content/groups/public/</url><releases><enabled>true</enabled></releases><snapshots><enabled>false</enabled><updatePolicy>never</updatePolicy></snapshots></repository>
</repositories><dependencies><dependency><groupId>org.elasticsearch.client</groupId><artifactId>elasticsearch-rest-high-level-client</artifactId><version>7.6.1</version></dependency><dependency><groupId>org.apache.logging.log4j</groupId><artifactId>log4j-core</artifactId><version>2.11.1</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.62</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version><scope>test</scope></dependency><dependency><groupId>org.testng</groupId><artifactId>testng</artifactId><version>6.14.3</version><scope>test</scope></dependency>
</dependencies><build><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><version>3.1</version><configuration><target>1.8</target><source>1.8</source></configuration></plugin></plugins>
</build>

3、创建用于保存职位信息的实体类

注意：

在id字段上添加一个 @JSONField注解，并配置注解的serialize为false，表示该字段无需转换为JSON，因为它就是文档的唯一ID。

参考代码：

public class JobDetail {// 因为此处无需将id序列化为文档中@JSONField(serialize = false)private long id;            // 唯一标识private String area;        // 职位所在区域private String exp;         // 岗位要求的工作经验private String edu;         // 学历要求private String salary;      // 薪资范围private String job_type;    // 职位类型（全职/兼职）private String cmp;         // 公司名private String pv;          // 浏览量private String title;       // 岗位名称private String jd;          // 职位描述public long getId() {return id;}public void setId(long id) {this.id = id;}public String getArea() {return area;}public void setArea(String area) {this.area = area;}public String getExp() {return exp;}public void setExp(String exp) {this.exp = exp;}public String getEdu() {return edu;}public void setEdu(String edu) {this.edu = edu;}public String getSalary() {return salary;}public void setSalary(String salary) {this.salary = salary;}public String getJob_type() {return job_type;}public void setJob_type(String job_type) {this.job_type = job_type;}public String getCmp() {return cmp;}public void setCmp(String cmp) {this.cmp = cmp;}public String getPv() {return pv;}public void setPv(String pv) {this.pv = pv;}public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}public String getJd() {return jd;}public void setJd(String jd) {this.jd = jd;}@Overridepublic String toString() {return "JobDetail{" +"id=" + id +", area='" + area + '\'' +", exp='" + exp + '\'' +", edu='" + edu + '\'' +", salary='" + salary + '\'' +", job_type='" + job_type + '\'' +", cmp='" + cmp + '\'' +", pv='" + pv + '\'' +", title='" + title + '\'' +", jd='" + jd + '\'' +'}';}
}

4、​​​​​​​编写接口和实现类

cn.it.elasticsearch.service包中创建JobFullTextService接口，该接口中定义了职位全文检索相关的Java API接口。

参考代码：

/*** 定义JobFullTextService*/
public interface JobFullTextService {// 添加一个职位数据void add(JobDetail jobDetail);// 根据ID检索指定职位数据JobDetail findById(long id) throws IOException;// 修改职位薪资void update(JobDetail jobDetail) throws IOException;// 根据ID删除指定位置数据void deleteById(long id) throws IOException;// 根据关键字检索数据List<JobDetail> searchByKeywords(String keywords) throws IOException;// 分页检索Map<String, Object> searchByPage(String keywords, int pageNum, int pageSize) throws IOException;// scroll分页解决深分页问题Map<String, Object> searchByScrollPage(String keywords, String scrollId, int pageSize) throws IOException;// 关闭ES连接void close() throws IOException;
;
}

5、​​​​​​​创建实现类

在cn.it.elasticsearch.service.impl包下创建一个实现类：JobFullTextServiceImpl，并实现上面的接口。

参考代码：

public class JobFullTextServiceImpl implements JobFullTextService {@Overridepublic void add(JobDetail jobDetail) {}@Overridepublic void update(JobDetail jobDetail) {}@Overridepublic JobDetail findById(long id) {return null;}@Overridepublic boolean deleteById(long id) {return false;}@Overridepublic List<JobDetail> searchByKeywords(String keywords) {return null;}@Overridepublic Map<String, Object> searchByPage(String keywords, int pageNum, int pageSize) {return null;}@Overridepublic Map<String, Object> searchByScrollPage(String keywords, String scrollId, int pageSize) {return null;}
}