新建项目过程省略
1.首先pom.xml引入Maven依赖
<!--mybatis-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.1</version>
</dependency>
2.application.yml配置mysql数据库 并且整合Mybatis框架
项目结构如下图(只需要关注箭头所指处):
spring:#配置mysql数据库
datasource:
username: root
password: *****
#?serverTimezone=UTC解决时区的报错
url: jdbc:mysql://localhost/Mybatis?
serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
driver-class-name: com.mysql.cj.jdbc.Driver
#整合mybatis
mybatis:
type-aliases-package: com.springboot.systemmanage.systemmanage.pojo
mapper-locations: classpath:mybatis/mapper/*.xml
3.编写配置文件编写代码
UserMapper.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.springboot.systemmanage.systemmanage.mapper.UserMapper">
<select id="queryUserList" resultType="User">/*即使是List resultType返回类型 也为User类型*/
select * from user
</select>
<select id="queryUserById" resultType="User">/*resultType返回类型 也为User类型*/
select * from user where id=#{id}
</select>
<insert id="addUser" parameterType="User">/*parameterType 传递参数为User类型*/
insert into user(id,name,pwd) values (#{id},#{name},#{pwd})
</insert>
<update id="updateUser" parameterType="User">/*parameterType 传递参数为User类型*/
update user set name=#{name},pwd=#{pwd} where id=#{id}
</update>
<delete id="deleteUser" parameterType="int">/*parameterType 传递参数为Int类型*/
delete form user where id=#{id}
</delete>
</mapper>
User对象
/**
* @Author MRyan
* @Date 2020/2/9 18:21
* @Version 1.0
*/
@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
private int id;
private String name;
private String pwd;
}
UserMapper
/**
* @Author MRyan
* @Date 2020/2/9 18:16
* @Version 1.0
*/
//Repository将DAO类声明为Bean 其次在xml配置文件中启动spring自动扫描功能
@Mapper
@Repository
public interface UserMapper {
List<User> queryUserList();
User queryUserById(int id);
int addUser(User user);
int updateUser(User user);
int deleteUser(int id);
}
最后使我们的实现代码部分:
UserController.java
/**
* @Author MRyan
* @Date 2020/2/9 18:50
* @Version 1.0
*/
@RestController
public class UserController {
@Autowired
private UserMapper userMapper;
//查询所有用户
@GetMapping("/queryUserList")
public List<User> queryUserList(){
List<User> users = userMapper.queryUserList();
return users;
}
//根据id查询一个用户
@GetMapping("/queryUserById/{id}")
public String queryUserById(@PathVariable(value = "id") int id){
User user = userMapper.queryUserById(id);
return "success insert"+user;
}
//添加一个用户
@GetMapping("/addUser")
public String addUser(){
userMapper.addUser(new User(5,"MRYAN","123456"));
return "success add";
}
//修改用户
@GetMapping("/updateUser")
public String updateUser(){
userMapper.updateUser(new User(5,"MRYAN","123456"));
return "success update";
}
//根据id删除一个用户
@GetMapping("deleteUser/{id}")
public String deleteUser(@PathVariable(value = "id") int id){
userMapper.deleteUser(id);
return "success delete";
}
}
以上就整合了Mybatis简单实现了增删改查功能