1、导入JDBC、MySQL、MyBatis的依赖
>
>
>org.springframework.boot >
>spring-boot-starter-data-jdbc >
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>org.springframework.boot >
>spring-boot-starter-jdbc >
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>org.springframework.boot >
>spring-boot-starter-web >
>
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>org.mybatis.spring.boot >
>mybatis-spring-boot-starter >
>2.1.2 >
>
>
>mysql >
>mysql-connector-java >
>compile >
>
>
>org.springframework.boot >
>spring-boot-starter-test >
>test >
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>org.junit.vintage >
>junit-vintage-engine >
>
>
>
>
2、编写实体类
public class User {
private int id;
private String name;
private int age;
3、编写DAO层接口
package springboot06datamysql.Mapper;
import org.springframework.stereotype.Repository;
import springboot06datamysql.Entity.User;
@Repository
public interface UserMapper {
//增加一个成员
public void insertUser(User user);
//删除一个成员
public void deleteUser(int id);
//查找一个成员
public User selectUser(int id);
}
4、在mapper.xml中匹配DAO的方法
<?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="springboot06datamysql.Mapper.UserMapper"//DAO接口的全类名>
<insert id="insertUser" parameterType="springboot06datamysql.Entity.User" >
insert into employee values(#{id},#{name},#{age})
</insert>
<delete id="deleteUser" parameterType="int">
delete from employee where id = #{id}
</delete>
<select id="selectUser" parameterType="int" resultType="springboot06datamysql.Entity.User">
select * from employee where id = #{id}
</select>
</mapper>
5、编写service层
package springboot06datamysql.Service;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import springboot06datamysql.Entity.User;
import springboot06datamysql.Mapper.UserMapper;
@Service
public class UserService {
@Autowired
UserMapper userMapper;
public void insert(User user){
userMapper.insertUser(user);
}
public void delete(int id){
userMapper.deleteUser(id);
}
public User select(int id){
User user = userMapper.selectUser(id);
return user;
}
}
6、编写controller层
package springboot06datamysql.Controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import springboot06datamysql.Entity.User;
import springboot06datamysql.Service.UserService;
@RestController
public class controller {
@Autowired
UserService userService;
@GetMapping("/insert")
public void insert(User user){
userService.insert(user);
}
@GetMapping("/delete/{id}")
public void delete(@PathVariable("id") int id){
userService.delete(id);
}
@GetMapping("/selete/{id}")
public User selete(@PathVariable("id") int id){
User user = userService.select(id);
return user;
}
}
7、编写响应的配置文件
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://xxx?serverTimezone=UTC
username: xxx
password: xxx
mybatis:
mapper-locations: classpath:mapping/mapper.xml
8、在主配置类添加Mapper扫描
@MapperScan(value = "springboot06datamysql")
@SpringBootApplication
public class SpringBoot06DataMysqlApplication {
public static void main(String[] args) {
SpringApplication.run(SpringBoot06DataMysqlApplication.class, args);
}
}
1、没有在主配置类上加Mapper的扫描,导致UserMapper注入失败
2、在select方法对应的mapper中,忘记了写返回值类型