SpringBoot数据访问之整合mybatis注解版

创建数据库：

use  vuesite;
CREATE TABLE city
(
    id      INT PRIMARY KEY auto_increment,
    name    VARCHAR(255),
    state   VARCHAR(255),
    country VARCHAR(255)
);

 创建实体类：

package com.xbhog.pojo;

import lombok.Data;

@Data
public class City {
    private Long id;
    private String name;
    private String state;
    private String country;
}

创建Mapper:

创建CityMapper并采用注解的方式实现sql映射的问题：

package com.xbhog.Mapper;

import com.xbhog.pojo.City;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

@Mapper
public interface CityMapper {
    @Select("select * from user where id = #{id}")
    public City getCityId(Long id);
}

创建Service:

package com.xbhog.service;

import com.xbhog.Mapper.CityMapper;
import com.xbhog.pojo.City;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class CityService {
    @Autowired
    CityMapper cityMapper;

    public City getCityId(Long id){
        return cityMapper.getCityId(id);
    }
}

使用Service注解声明，并将该类加入到容器中，方便后面调用，在service层调用Mapper层的方法。

创建Controller:

import com.xbhog.pojo.City;
import com.xbhog.service.CityService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.annotation.Resource;

@Controller
public class Mycontro {
    @Autowired
    CityService cityService;


    @ResponseBody
    @GetMapping("/city")
    public City getCity(@RequestParam("id") Long id){
        return cityService.getCityId(id);
    }
}

增加数据库信息：

 测试：

mybatis混合版：

我们在CItyMapper中添加一个方法：

package com.xbhog.Mapper;

import com.xbhog.pojo.City;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

@Mapper
public interface CityMapper {
    @Select("select * from city where id = #{id}")
    public City getCityId(Long id);

    public void addCity(City city);
}

这个方法我们采用配置文件来绑定。

创建CityMapper.xml文件：

<?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.xbhog.Mapper.CityMapper">
    
    <insert id="addCity" parameterType="com.xbhog.pojo.City">
        insert into city(`name`,`state`,`country`) values (#{name},#{state},#{country});
    </insert>
</mapper>

其中命名空间与CityMapper要对应，进行插入操作。

在Service层增加方法：

package com.xbhog.service;

import com.xbhog.Mapper.CityMapper;
import com.xbhog.pojo.City;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class CityService {
    @Autowired
    CityMapper cityMapper;

    public void addCity(City city){
        cityMapper.addCity(city);
    }
}

https://www.cnblogs.com/xbhog/p/15201414.html