zhangbeizhen 2019-11-09
controller 定义路由
service 业务逻辑处理
entity 实体类 与数据库中的表一一对应
mapper 数据库操作,定义对数据库各种CUDR的接口,myBatis框架会自动生成实体类
mapping 数据库操作的XML文件,通过namespace 与 mapper一一对应,通过每一项中的id对应接口类中定义的方法,通过每一项中的resultType对应实体类,表明数据返回的对象。
application.yml
spring: profiles: active: dev
application-dev.yml
server: port: 8080 spring: datasource: username: root password: 19961110 url: jdbc:mysql://47.95.110.227:3308/news?useUnicode=true&characterEncoding=utf-8 driver-class-name: com.mysql.cj.jdbc.Driver mybatis: mapper-locations: classpath:mapping/*Mapper.xml configuration: # 开始驼峰命名与下划线命名的转换 map-underscore-to-camel-case: true #showSql logging: level: com: example: mapper : debug
indexController.Java
package com.crxk.myBatisTset.controller; import com.crxk.myBatisTset.service.catService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; @Controller @ResponseBody public class indexController { @Autowired private catService catService; @RequestMapping("/getCat") public String getCat(int id){ return catService.getCat(id).toString(); } }
catService.java
package com.crxk.myBatisTset.service; import com.crxk.myBatisTset.entity.Cat; import com.crxk.myBatisTset.mapper.catMapper; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; @Service public class catService { @Autowired catMapper catMapper; public Cat getCat(int id){ return catMapper.getCat(id); } }
cat.java
package com.crxk.myBatisTset.entity; public class Cat { int catId; String catName; public Cat() { } public Cat(int catId, String catName) { this.catId = catId; this.catName = catName; } public int getCatId() { return catId; } public void setCatId(int catId) { this.catId = catId; } public String getCatName() { return catName; } public void setCatName(String catName) { this.catName = catName; } @Override public String toString() { return "Cat{" + "catId=" + catId + ", catName='" + catName + '\'' + '}'; } }
catMapper.java
package com.crxk.myBatisTset.mapper; import com.crxk.myBatisTset.entity.Cat; import org.apache.ibatis.annotations.Mapper; @Mapper public interface catMapper { Cat getCat(int id); }
catMapper.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.crxk.myBatisTset.mapper.catMapper"> <select id="getCat" resultType="com.crxk.myBatisTset.entity.Cat"> select * from cat where cat_id = #{id} </select> </mapper>